B18 Connecting Rod Question CROWER & EAGLE

[adams86lxi]

Ok well im doin alot of research for me and basically for all of us of what might work for piston/rod combo's in are cars. I got enough friends with enough spare parts from different engines to compare alot of them too. Well so i remember seeing somewhere on here that b18a1 rods fit perfect? Is this true? Im not worried about the wrist pins slots being to big or small for are pistons im just talking about they fit on the crank perfect right? What bearings would i use the a20 bearings on the b18 rods or the b18 rod bearings?? Umm if this true about these rods then i think ive made a nice little discovery but i dont wanna say it until im sure this would work lol....

[Legend_master]

Ok well im doin alot of research for me and basically for all of us of what might work for piston/rod combo's in are cars. I got enough friends with enough spare parts from different engines to compare alot of them too. Well so i remember seeing somewhere on here that b18a1 rods fit perfect? Is this true? Im not worried about the wrist pins slots being to big or small for are pistons im just talking about they fit on the crank perfect right? What bearings would i use the a20 bearings on the b18 rods or the b18 rod bearings?? Umm if this true about these rods then i think ive made a nice little discovery but i dont wanna say it until im sure this would work lol....


I don't know anything from experience on this one, but I would assume you use the b18 rod bearing. I also think the b18 rod is longer then the a20 rod, but don't quote me on that one. If this was true I wonder how much and if this could be used to make higher compression or some form of a stroker kit. I also looked into other motors with 3 valves per cylinder so we could use the pistons to lower or raise the compression, had no luck on that one.

[bobafett]

LS rods will work PERFECTLY, but you need to be using a 21mm wrist pin, as opposed to 19mm or 20mm, or whatever the stock A20 uses. there 'may' be a way to modify the stock pistons to use 21mm pins, but honestly if ur bothering to get rods, ur probably also bothering to get pistons, and anyone who builds pistons for u can set you up with 21mm wrist pins and then your all set.

this works with stock a20 bearings AFAIK.

i have been using Eagle H-Beam LS rods in my motor with no problems at all. :D

[Legend_master]

LS rods will work PERFECTLY, but you need to be using a 21mm wrist pin, as opposed to 19mm or 20mm, or whatever the stock A20 uses. there 'may' be a way to modify the stock pistons to use 21mm pins, but honestly if ur bothering to get rods, ur probably also bothering to get pistons, and anyone who builds pistons for u can set you up with 21mm wrist pins and then your all set.

this works with stock a20 bearings AFAIK.

i have been using Eagle H-Beam LS rods in my motor with no problems at all. :D

Guess I was wrong on all my points. So has anybody compared the b18 crank to the a20 crank. I wonder if they are similar

[bobafett]

different strokes, but i am not sure about diameters.

we have 91mm stroke vs their 87mm stroke i believe.

[bobafett]

http://www.horsepowerfreaks.com/price/Acura/Integra/Eagle/Engine/Connecting_Rods/part/H_Beams_4340_Forged_Chromoly_Steel
we want the non-vtec rods. thats exactly what i am useing. i know they work just fine :D

[Legend_master]

http://www.horsepowerfreaks.com/price/Acura/Integra/Eagle/Engine/Connecting_Rods/part/H_Beams_4340_Forged_Chromoly_Steel
we want the non-vtec rods. thats exactly what i am useing. i know they work just fine :D


just to let you know the only difference between the vtec and non vtec is the area where the wrist pins go.

[bobafett]

cool. i didn't know that.

do you know specifically what the differences are?

[adams86lxi]

LS rods will work PERFECTLY, but you need to be using a 21mm wrist pin, as opposed to 19mm or 20mm, or whatever the stock A20 uses. there 'may' be a way to modify the stock pistons to use 21mm pins, but honestly if ur bothering to get rods, ur probably also bothering to get pistons, and anyone who builds pistons for u can set you up with 21mm wrist pins and then your all set.

this works with stock a20 bearings AFAIK.

i have been using Eagle H-Beam LS rods in my motor with no problems at all. :D


thanks for your help guys!!! This is awesome news!! Sooo has anyone ever tried to use the b18 pistons with the b18 rods?

[bobafett]

they are way too small if i recall. :(

http://www.superhonda.com/forum/archive/index.php/t-125367.html

but according to that page, b20 pistons are 84mm, which is .050 overbore, which is what I am running. :D not know why the pistons wouldnt work if we are using the b series rod too. something to think about i suppose!

[adams86lxi]

they sell b18c1 pistons in a 83mm?? Will those work with b18a rods?? My current pistons are 83mm so this would be awesome..


http://cgi.ebay.com/ebaymotors/CP-Pistons-83mm-9-1-Acura-Integra-B18C1-B18-GSR-VTEC_W0QQcmdZViewItemQQcategoryZ33623QQitemZ804150 8857QQrdZ1QQsspagenameZWD1V

[bobafett]

dunno what the compression would look like on a20, or if the pin location on those pistons is in a compatible location (ie would pistons go too far up, not far enough?)

[Legend_master]

you can get b18 pistons in any bore you want Check here (http://hondamarketplace.com/zerothread?id=1569878), but I don't think think the 4 valve per cylinder designed piston will work with a 3 valve head unless you go low compression. As for the 18a/b and b18c rod difference all I can tell you is that you have to have the rod shaved out to put a vtec piston on a non vtec rod (I am only speaking of LS integra rods and GSR pistons).


P.S. the LS rods are a little longer then the gsr rods

[AccordEpicenter]

the pin height is much different or so im told, im gonna borrow an ls piston/rod combo and see how it sits

[adams86lxi]

alright well the reason i brought this whole thing up is i had a set of my friends old b18 rods and pistons sitting around and decided to see how they sit in are blocks and they look like they would fit PERFECTLY!!! And im serious... b18a/b pistons and rods seem to be the perfect height with are block/crank....

on the left is the b18 piston/rod and on the right is the stock a20 piston/rod. The engine is at tdc...

Remember these pistons are way too small for my bore so dont mind the big gap between the cyl walls and pistons but other then that they seem to be the perfect height!!

Check it out!!!

http://i34.photobucket.com/albums/d144/b20accord/DSCF0362.jpg

http://i34.photobucket.com/albums/d144/b20accord/DSCF0361.jpg

http://i34.photobucket.com/albums/d144/b20accord/DSCF0360.jpg

http://i34.photobucket.com/albums/d144/b20accord/DSCF0359.jpg

[gfrg88]

THANK YOU ADAM!!!!!! ive been trying to see why that wouldnt work!!!! i always wanted to try that out but i didnt have any b18 parts to work with, but you just found out some great things for us!!!!!! looks like its time for me to start building an engine ;)

[adams86lxi]

THANK YOU ADAM!!!!!! ive been trying to see why that wouldnt work!!!! i always wanted to try that out but i didnt have any b18 parts to work with, but you just found out some great things for us!!!!!! looks like its time for me to start building an engine ;)


lol no problem man!!! I couldnt belive it once i saw that they were perfect fit for us!! I dont understand how no one hadn't relized this before lol....

[rjudgey]

The only problem i can see is that the inlet valve relief pockets aren't quite in the right place, and also there is a deeper dish to the B18 piston so CR ratio will be lower especailly as the vlave relief pockets are really big too. I would order up a set without the valve relief pockets in just plain flat top and have just a 3 valve relief pockets machined into the right place to suit our heads, and obviously a 82.7 or 83mm size piston to fit our blocks and that would be perfect best CR for NA guys or if you are running turbo then have a Deep dish machined into the top to drop the CR ratio and have the valve relief pockets machined so they fit with the valves although with Turbo guy's running less duration and lift shouldn't be too much of a problem with vlaves hitting pistons anyway.

[bobafett]

the stock pistons have 4 valve reliefs, not sure if they are in the exact same spot as the b-series pistons or not, but it would be easy enough to check visually. :)

since you can order b-series pistons in particular sizes, like 83mm, this does open up a lot of options, but we have to keep in mind we don't know what the real CR would be. maybe a quick call to diamond would help figure this out. if they ended up making us custom 'b-series' pistons it would probably be cheaper anyway. :)

this is cool news though.

[adams86lxi]

yea im pretty sure the valve reliefs wont be too much of a problem though, in my case atleast... I would be using mostlikely low compression dished ones so there will be even more room for the valves... But im pretty sure even with comparing the 2 pistons the way they are in the block the valves wouldnt hit... I have put pistons in my old b20 where the valve reliefs were WAY different and it didnt give me a problem at all! I cant be positive though but i dont see it affecting us unless we get high compression ones where it has a domed shaped to it.

[AccordEpicenter]

id bust out a micrometer and see how much the difference really is in the pin height from the top face of the piston, it looks slightly different to me but maybe its just the pic/angle or the fact that its not the right bore lol. Can you measure them and post a pic side by side comparing the pin heights in the pistons adam? And yea, to make this even semi viable somebody needs to sit down and play doh the piston and see where the valves are gonna end up and if they are gonna hit, since the reliefs are much different.

[Legend_master]

Alright we can use this compression calculator (http://www.c-speedracing.com/howto/compcalc/compcalc.php), but we have to fill in all the Info manually. I know the bore and stroke, but I am not sure abour the Combustion Chamber Volume or the Piston-to-Deck Height.

[carotman]

Nice stuff!!

[adams86lxi]

alright guys im still having trouble finding b18a/b pistons in 83mm... anyone want to point me the right way?? I can find them for the b18c but not for the a/b!!

[gfrg88]

alright guys im still having trouble finding b18a/b pistons in 83mm... anyone want to point me the right way?? I can find them for the b18c but not for the a/b!!


guess youre going to have to get some new pistons and rods then, that just means more boost for you ;)

[AccordEpicenter]

adam id just call up diamond. Mine were like $470 shipped, rings and pins included.

[Legend_master]

Well with some # I got from bobaffet the compression with stock b18a rods and stock b18a pistons comes out to be, 9.6:1 at 2003. cc's

[gfrg88]

Well with some # I got from bobaffet the compression with stock b18a rods and stock b18a pistons comes out to be, 9.6:1 at 2003. cc's


thats a good, but would that be too much for boost?? maybe 5psi of boost should be good with nice tune you could run more right?

[bobafett]

hmm. for all the trouble i would just order custom pistons and get the CR you want, overall its not much more money, but it will make a world of difference in what you want for your car. 9.6 might be too high for some, too low for others. :D

[AccordEpicenter]

9.6:1 is fairly boost friendly, but for the money you guys are spending, id just get the custom pistons to suit your needs

[AccordEpicenter]

10.5:1? Ehh that is a little high for me but with the right tune and good enough fuel you should be fine. Its just a little harder to tune but you will make ALOT more power at the same boost level than say 8.5:1

[gfrg88]

i wanna see what youre making after youre done with your build :rockon:

[smufguy]

Adam, what about the Crankshaft? How does a B18 Crank fit in the A20? Can you take pictures of the B18 crank sittin on the A20 block please?:)

[bobafett]

hmm if we used b-series cranks then we could use their crank gears and cam gears. :) assuming they are even close enough to fit. somehow i get the feeling an a20 crank will be more beefy than a b18 crank though. but thats just a guess

[AccordEpicenter]

I dont think we need to worry about cranks too much, guys. This b series piston stuff is already making my head spin, lol. And ohhh yeahhh... im going for ALOT of power (id like to keep some things from the suspecting public)

[adams86lxi]

Adam, what about the Crankshaft? How does a B18 Crank fit in the A20? Can you take pictures of the B18 crank sittin on the A20 block please?:)


yes i can!! Ill borrow my friends and see how it fits!

[smufguy]

yes i can!! Ill borrow my friends and see how it fits!

u da man. u da man :cheers:

[Kabuki]

Oh, guys? Yeah the B Series cranks won't fit in the A20. The main journals of the A20A are 50mm, and the B18A are 55mm. The A20A block would need to be align-bored with the larger measurement to accept those crankshafts. So that also won't work to fix our short timing pulley problem on the hybrid B20A/A20A engine either.
*Sigh*

[Legend_master]

Oh, guys? Yeah the B Series cranks won't fit in the A20. The main journals of the A20A are 50mm, and the B18A are 55mm. The A20A block would need to be align-bored with the larger measurement to accept those crankshafts. So that also won't work to fix our short timing pulley problem on the hybrid B20A/A20A engine either.
*Sigh*

Having the journals bored would be a plausible factor, but I don't know the price or if it would even help us to have it done.

[Kabuki]

Yes, but.... If you do that, i think you may end up with needing a custom timing gear... Oh, I just realized what the problem is. Crap. The reason that the B series cranks, and cams are all longer than the A series is that the A series oil pump is external. The B's need the extra length to drive the oil pump. So even IF you were to bore the block to fit the crank, the snout end sealing surface will not line up. AAAArrrrrrgh!

[Legend_master]

Yes, but.... If you do that, i think you may end up with needing a custom timing gear... Oh, I just realized what the problem is. Crap. The reason that the B series cranks, and cams are all longer than the A series is that the A series oil pump is external. The B's need the extra length to drive the oil pump. So even IF you were to bore the block to fit the crank, the snout end sealing surface will not line up. AAAArrrrrrgh!


yep I dident even think of that, you are right DAMN that sucks :violin:

[guaynabo89]

ALright guys I have some info that might be new. Dont know if its been posted before but here goes.
Another member was inquiring about the rods in my engine and we had a little chat on aim and I dug out the specs. Well this sparked my interest to find out if the part number was still a good part number since I had my rods custom made about 10 years ago. I sent an email to crower inquiring about my old part number to see if there was a new part number for a part that they already kept in stock. The answer to that was no. The part number on my rod tag is a custom part number.
There is good news though. I replied to the rep at crower and told him that the last time I spoke to someone over there they told be that the rods in the a20 were the same exact size as another populer HOnda engine just different pin size diameter. I gave him all the specs and measurements and asked him to compare to the rods they do stock for similarities.
The GOOD neews is he replied! :D
Well it seems the a20 rod is the same size as the b18a/b and the b20b but with one small difference. The a20 uses a 20mm pin diameter while the b18/b20 use a 21mm pin diameter. Which is what I was told 10 years ago. lol
With this info you can either buy rods for either of those engines (b18 b20) and have pistons custom made to use a 21 mm pin, or you can use those rods and have either crower or a reputable shop install a different bushing in the pin end of the rod at the size of 20mm.
The B18a/b engines Im prety sure are the ls engines in the integras from 1990 and up and the b20b I think is the crv. Someone corect me if Im wrong cause Im not positive about the years and models.
This is the last response I got from the rep including the part number the a20 rods most closely match.
"We can make the rod on a custom order basis for $743.34. 6-8 week lead time. This rod is the same as our part # B93728B-4 but with a different pin size. If you have any questions please call 619-690-7806. Thank you for your interest in crower."
Now i know crower are a little up there in price but they are one of the best (hence why I got them) but with this info you can get econo rods maybe or if you get a good deal you'll know what to look for.
If this infos not already in the faq or somewhere this should be made a sticky somewhere.
Again I dont know if anyone out there has already figured this it but if not this is definately some good info for anyoe building an a20.

[shepherd79]

actually B20B is CRV motor.

[MessyHonda]

i thought we could use 83mm b-series pistons?

[guaynabo89]

actually B20B is CRV motor.


ok fixed.

so what you guys think..... interesting, already know, or what. I havent had to look for rods in a while so I dont know what other discoveries 3geez members have made.

I dont know about the pistons other than 83mm sounds like the bore size. if thats the case we can just order those 83mm pistons to fit the a20 and hopefully they do have the 21mm pin diamnter and get the b18.b20 rods and there we go. no need to custom anythign.

right off the shelf?

What you guys think?

Can someone verify this?

[ZackieDarko]

very intresting

[snoopyloopy]

well, i know adam had mocked up some b18a parts in his a20a3 block, but i don't think he ever actually ran it. but that's what he told us. that the b18a/b rods fit, you just need to either get new wrist pins or pistons that fit. then in another thread, he showed that the b18a piston apparently fits as well. so yeah, b18a/b rod/piston combo sounds like it'll fit. the b20b i don't know about, but i'll take a gander that it isn't much different.

[rjudgey]

The only problem he had was that the B18 pistons he had were only 81mm or 82mm so they didn't fit properly but couple of makes of pistons do 83mm which would be perfect for us as we can bore out to that size, now i'm not sure if the height of the pistons are the same we need someone to confirm that first, secondly if they are the same then they would fit we would need to ask the piston supplier to make a B18 piston with 83mm bore and to have a blank flat top crown so that we can have our own valve pockets machined to fit our chambers, advantage of this will be B18 spec rings bit less friction as they are performance orientated more, Higher CR ratio as they'll be flat tops and bigger bore and we'd be able to get just 3 valve pockets machined instead of 4 in each piston like the stock ones. Also being forged they'll be stronger and a little lighter, now all we need now is titanium wrist pins!!

[snoopyloopy]

http://www.3geez.com/forum/showthread.php?t=52447
b18a rod/pistons ------ a20a rod/pistons
http://i34.photobucket.com/albums/d144/b20accord/DSCF0362.jpg

[azazel_18_2]

You COULD just have three pockets machines in the pistons but why waste the money? Honestly. Have you seen the tops of your pistons? They have four valve reliefs not just three. 83mm is b18 pistons .080 oversized. I did research on this and posted it and got flamed because you can buy Diamond pistons cheaper than the 83mm forged pistons. If you find a place that sells the b18 83mm pistons for less than $600 then we would be in business. I know my diamond pistons were $500-600 I don't remember exactly how much they were.

[rjudgey]

You have the 3 valve pockets to increase the CR ratio, if you have 4 it means you have one valve pocket increasing the volume on the crown of the piston which will lower you CR ratio especially as it's the exhaust one which is bigger than the inlet valve pockets. Might only be a small decrease but with all the rest of the pockets not lining up you'd have to remachine them bigger anyways so your paying to have it done anyways and also you'll loose even more CR ratio because your increasing the volume on the dish of the piston. Having them made with blank crowns is much better they may even do it a bit cheaper. Failing that just get the Diamond ones and maybe ask them just to do 3 valve reliefs and have the rods re-bushes for 20mm pins which are lighter than 21mm but then 21mm are stronger if your running boost better off with 21mm or extreme rpm 21mm is better but if you can have titanium ones made that should help increase reliability.

[bobafett]

lol good post man, but welcome to last year! :D jp, hehe

i am using eagle H-beam RODS in my a20. they are the part number from an LS integra. and you are exactly right, i had to have custom pistons made with a 21mm wrist pin.

it would be interesting to see if we could get b series pistons to fit, but chances are you are going to be buying nice forged pistons anyway, so you might as well order them with a20 specs and then get the right size pins installed.

from diamond racing, pistons, rings and locks were like 550 ish, and off the shelf rods for LS teg was around 300. :)

but still, its good to spread the word so that more people realize what is possible.

[rjudgey]

Thing is though i'm after a flat top piston with just 3 valve reliefs so i don't think Diamond will have that? And also i think the frictional losses on the B18 rings might be slightly better than A20 ones. Still not sure on what would be best i think i'll just have to get my engineer to sort it out but custom made pistons in U.K. cost a shit load so getting a B18 83mm piston with a blank crown and having my engineer machine in custom pockets would be a lot better and cheaper. Plus he wouldn't have to charge me for re-bushing the rods too as they'd be the same size.

[bobafett]

is pin height close enough to not throw off compression?

also, I don't know whether or not diamond would/could make a piston with only 3 reliefs... hmm who knows.

[guaynabo89]

lol good post man, but welcome to last year! :D jp, hehe

i am using eagle H-beam pistons in my a20. .

H beam pistons huh.....I need a set of those lol j/k

bujt yeah sorry. I guess I should have posted this info back when I found he board instead of waiting until now. lol just didnt search is all

but eah is this info in the faq somewhere though if not it should be.

I got my wisecos made for about 450 ten years ago and whre so pretty I didnt want to put them in. lol Nice full floating pins indtead of the pressed sock kind and all.

flat tops shouldnt be a problem with any piston manufacurer.

I still have the piston from my block that I sent in to hve mine custom made so if anyone local wants to compare a b18 b20 piston I could et them mesuresd up to find out if the pin eight is the same in te piston. or of someone wants to mail me one I'll get them measure up and find out.

[bobafett]

oops trying to type fast while at work and not reading heheh u know what i mean ;)

[SQ is the SQUAD]

i though i cross referenced your part number to the starion rods, maybe i was wrong.

[AccordEpicenter]

i used crower b18b rods (ls rods) but my pistons have a 21mm wrist pin instead of the stock 19mm one. you might be able to get a custom set if you wanna reuse a stock pin size (why would you?)

[SQ is the SQUAD]

i used crower b18b rods (ls rods) but my pistons have a 21mm wrist pin instead of the stock 19mm one. you might be able to get a custom set if you wanna reuse a stock pin size (why would you?)


did u have to notch your block to use them?

[AccordEpicenter]

no

[MessyHonda]

no



so they are a bolt in?

[SQ is the SQUAD]

ummmm, i know someone who has some 85mm endyne rolerwave forgesd pistons and eagle rods. ha ha ha. i may have to borrow them.

my best friend is actually building his ls/vtec. i am talking crazy build. he has some eagle long rods but he was debating to use them or not, not sure if we can use "long" rods

heres his build
http://www.honda-tech.com/zerothread?id=1429424

[SiN360]

What integra rods can I use on a a20a3? I think they are lighter than the stock ones.

[LX-incredible]

These:
CRS5394A3D "ESP" H-Beam Connecting Rods $319.00
They don't seem to be lighter, but they are a lot stronger. There are others out there too, even titanium.

[ZackieDarko]

i have always been confused on this

does anybody know if it HAS to be these forged H-Beams or will ANY B18 (the "real" b-series) rods work?

[MessyHonda]

These:
CRS5394A3D "ESP" H-Beam Connecting Rods $319.00
They don't seem to be lighter, but they are a lot stronger. There are others out there too, even titanium.


can we use stock b-series rods?

[guaynabo89]

can we use stock b-series rods?


no

they use a larger wrist pin.

[MessyHonda]

no
they use a larger wrist pin.



we need a 19mm one right?

[AccordEpicenter]

Yes, but with an aftermarket piston with 21mm wrist pins or having the stock wrist pin holes in the pistons reamed out you should be able to use any b18A/B rod, including a stock rod. Stock honda rods are pretty good but the slight machine work to make another stock rod work in an a20 is just not worth it imo when you can get eagles for $300 ish when you consider the added strength and better fasteners in the eagles. Stock rods if used for any kind of performance build should have new rod bolts, have the big end resized, and shotpeened at least. All that stuff is not cheap.

[ZackieDarko]

so we can use ANY stock b-series rod if we had 21mm wrist pin pistons correct?

[AccordEpicenter]

only B18A/B rod, B16 and B18C1 and B18C5 use a different rod length and will not work

[ZackieDarko]

ah so they must be from an LS

im guessing the B17 GSR rods will not work as well

[AccordEpicenter]

correct

[MessyHonda]

alright...i was looking into this with some integra .080+ pistons...since they are 83mm bore. and it looks like an ok set up...or should we get custom pistons done. if im buying performance parts i would like a raise in compression since i plan on staying NA. trying to keep it a 150whp accord here.

[AccordEpicenter]

i thought the deck height was too different for those integra pistons, i would call diamond and get some forged pistons like i got, they were gorgeous.

[snoopyloopy]

i swear this thread needs to be stickied...

[AccordEpicenter]

you can see a difference in pin heights between the 2, just get custom pistons

[87lxiaccord]

i thought the deck height was too different for those integra pistons, i would call diamond and get some forged pistons like i got, they were gorgeous.
how much did you pay?

[bobafett]

diamond racing charged me about 550 for pistons + rings + locks etc.

and i have all kinds of weird shit done to my pistons :)

basically u are looking at like 1000 for pistons/rods/bearings :) but u will have snazzy ARP rod bolts, and nice bearings and if you get your bottom end balanced from crank pulley to clutch you will have a solid 8000rpm capable bottom end (just make sure your head can take it)

[MessyHonda]

diamond racing charged me about 550 for pistons + rings + locks etc.

and i have all kinds of weird shit done to my pistons :)

basically u are looking at like 1000 for pistons/rods/bearings :) but u will have snazzy ARP rod bolts, and nice bearings and if you get your bottom end balanced from crank pulley to clutch you will have a solid 8000rpm capable bottom end (just make sure your head can take it)


i just dont want to blow my bottom end....1k is a lil too much for me. plus like i said im tend on running this car in NA form....i would rather bump the compression with like teg pistons or something.

[bobafett]

Yeah but for the EXTRA cost, its one of those 'might as well do it now' things. If you just want NA rebuild thats one thing, but if your going high compression you will be tuning the care etc and you might as well get some insurance that your going to be able to rev that extra 1000 rpm. :) Cause you will want to...

EDIT:

and if you get teg pistons (LS anyway) you will have 21mm pin and need different rods anyway... and you BETTER do bearings, so you are already 1/2 way there to your 1k mark. and since you would be crazy to put in used pistons/rings (especially on commonly abused B motors) you need at minimum stock B pistons and rings, so you might as well pay the extra few hundred and get EXACTLY what you want to your specifications. want to lower the rings so you dont risk busting ringlands? sure no problem! :) heheh little things like that make a big difference between blown motor and happy motor. especially on high strung and 'well driven' motors

[AccordEpicenter]

im def with bobafett on this one guys. My pistons were a little cheaper than that also

[hondaman1986]

ok im sure that this has been asked to death and i couldnt find anything about them so... can anyone tell me what the connecting rod length is on an a20.

im planing on getting b18b con rods and i need to know how long the a20's are so i can match. anyone?

[ZackieDarko]

You can only use the rods from the B18A/B

[hondaman1986]

yes i know that but i would like to make sure that the ones I order are the correct length

also can someone tell me what size head studs i would use?

[ghettogeddy]

were did u buy them form and did u get stock replacements or performance links links links people

[hondaman1986]

were did u buy them form and did u get stock replacements or performance links links links people

i havent bought them yet they are eagle esp rods http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10551_754299_-1_11487
obviously the b18a/b rods

[ghettogeddy]

356-CRS5394A3D B18A/B DOHC non-VTEC
5.394'' Length
510 grams

[hondaman1986]

356-CRS5394A3D B18A/B DOHC non-VTEC
5.394'' Length
510 grams


yep thats them but are those the same length as our stock rods out of a a20 is what i am tring to figure out

[ghettogeddy]

Well I am going through my High Performance Honda Builder's Handbook and I am looking at the engine information. One thing that has jumped to me is Connecting Rod length.
The A20's rod length is 137mm. The D16 and B18A share the same rod length. This would mean that you could get stronger aftermarket rods for our A20s. Or am I missing something??

[hondaman1986]

thats what i needed thanks ghetto

[ghettogeddy]

137 millimeters = 5.39370079 inches

[hondaman1986]

137 millimeters = 5.39370079 inches


ok thanks.

[ghettogeddy]

so at $399 a set are these needed for a mild n/a build or if im gona go turbo

[hondaman1986]

all out n/a build mild now maybie more later. i say you can go ether way they are some vary strong rods

[ghettogeddy]

but vs just a new set of stock rods , heres the deal ill be running a a .50mm bore with .50mm over stock pistons, delta 272 cam, GE adj cam gear, P&P head with a 3angle valve job and a few others nothing fancy but looking for like 150 160 hp

[hondaman1986]

but vs just a new set of stock rods , heres the deal ill be running a a .50mm bore with .50mm over stock pistons, delta 272 cam, GE adj cam gear, P&P head with a 3angle valve job and a few others nothing fancy but looking for like 150 160 hp

dude im gonna run a .50mm overbore too and im going with the colt tri-flow and adj cam gear too as well as the 3 angle valve job so pretty much the same as you. remember that ppl are going 500+hp on the ls motors so our levels should be perfectly fine


::edit:: im also gonna through a little NOS at mine. like a 50hp jet at the most but im all carb

[ghettogeddy]

but do i really really need them lol

[hondaman1986]

but do i really really need them lol


ah yes the age old question we all get. lol i say try the stockers if you would like to save some money but everyone on here is going with them or simaler.


oh yea i cant spell even though im in college lol

[snoopyloopy]

just remember that when you get those rods, you either have to get your stock pistons machined to fit or get some custom-made to fit. or the alternative, be the first to actually try the b18a/b rods and pistons and see if it actually will work. there's a lot of naysayers who say it doesn't, but to my knowledge, i don't recall seeing anyone actually try to run it. the closest i've seen is adam putting the b18a/b rod-piston combo in an a20 block.

[hondaman1986]

is there enough material left on the stock pistons wrist pin area to still be stable?

[snoopyloopy]

is there enough material left on the stock pistons wrist pin area to still be stable?
? i think so. i *think* accordtheory is running an ls/a20 rod-piston combo in his turbo motor and it has apparently held up alright. so i assume that there is.

[hondaman1986]

? i think so. i *think* accordtheory is running an ls/a20 rod-piston combo in his turbo motor and it has apparently held up alright. so i assume that there is.

ok thats reasuring

[cygnus x-1]

Unless you're using forged pistons I don't see the point of upgrading the rods. You should probably use ARP rod bolts though. These are the ones that fit A20 rods: ARP 208-6001
They need to be modified very slightly, I believe to grind down the bolt heads to fit. Not sure exactly as the shop did mine.

Incidentally with my rebuild I used stock rods and pistons with the following:
Weber carb
mild port/polish and performance 3-angle valve job
Colt triflow cam (stage 1)
S&S header (still waiting for coating)

C|

[ZackieDarko]

if the A, B and D rods are all the same lengeth and have the same bottom end (which they do)

and the A and D have the same size wrist pin (19mm) couldn't we just get some D16 rods and use them with stock pistons? TunerToys makes some great rods for the D...why not get some of those and just cryo treat some DX pistons?

[hondaman1986]

eagle makes some great rods for the d seires too here take a look (http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10551_754299_-1_11487)

[ZackieDarko]

hmmmm this excites me imgonna see if i can get a hold of some D rods and try this out

[hondaman1986]

i wonder if there is any real diffeance between the two eagle rods they seem to be the same exept for the wrist pins. also the stock d16 rods are only good for 220hp at the most so it makes me wonder if the b18 rods would be better or if the d16's are. hmmm ill give them a call if i can

[cygnus x-1]

How much does cryo-treating cost?

C|

[ZackieDarko]

if somebody could find a 21mm to 19mm bushing we could use the B18 rods with stock pistons

[hondaman1986]

if somebody could find a 21mm to 19mm bushing we could use the B18 rods with stock pistons


as far as i know you never will because to have that adapter you would have to have a 2 piece wrist pin just causeing it to fail quickly... like the first start up

it would be cool as heck if they made them though

[ZackieDarko]

i have been doing some research on a 21mm to 19mm bushing


crower used to make brass ones so the D guys could rock LS rods without geting custom pistons...but alas they no longer do this :(

[rjudgey]

bushing can be replaced with smaller or larger one, old one is machined out new one made and pressed back in. Not hard when done by someone who knows what there doing off.

[rjudgey]

Oh biggest problem is that the rod would be a floating pin but the piston is designed for a fixed pin so not sure how you would get around that other than custom forged or B18 piston at 83mm with a blank top and then have the crown machined for our 3 valve chambers.

Also last time i measured my A20 wrist pins they were 20mm? Also my stock rods were good upto 200bhp but they didn't take to well to revving upto 7.5k rpm completely stock but balanced lasted 30k miles then they snapped at the neck completely off two at the same time!!! Like a grenade going off inside was quite spectacular!!!

For the price of the Eagle rods e.g. bugger all i would get them and then have the B18a/b pistons made up at 83mm size and have blank crowns, then have a engine specialist machine the crowns to match our heads. Or just have JE/Wiseco to custom make them to our needs (which would probably be more) But then again doesn't diamond have a pattern for our engines for the Eagle rod size wrist pins?

[MessyHonda]

Oh biggest problem is that the rod would be a floating pin but the piston is designed for a fixed pin so not sure how you would get around that other than custom forged or B18 piston at 83mm with a blank top and then have the crown machined for our 3 valve chambers.
Also last time i measured my A20 wrist pins they were 20mm? Also my stock rods were good upto 200bhp but they didn't take to well to revving upto 7.5k rpm completely stock but balanced lasted 30k miles then they snapped at the neck completely off two at the same time!!! Like a grenade going off inside was quite spectacular!!!
For the price of the Eagle rods e.g. bugger all i would get them and then have the B18a/b pistons made up at 83mm size and have blank crowns, then have a engine specialist machine the crowns to match our heads. Or just have JE/Wiseco to custom make them to our needs (which would probably be more) But then again doesn't diamond have a pattern for our engines for the Eagle rod size wrist pins?


that would be the best idea get some 83mm b18a pistons and rods...so that would be .030 over on the block

[ZackieDarko]

i have looked or 83mm b pistons but havent found shit :(

[hondaman1986]

ok the wrist pin from the D is 19 mill. so anyone know for sure what our's is???

[AccordEpicenter]

d series stock rods are junk, used stock a series rods are much better

[ghettogeddy]

d series stock rods are junk, used stock a series rods are much better
but for a low n/a hp build would stock connection rods be fine maybe a good brand name set any suggestions

[hondaman1986]

ok im might be buying aftermarket D rods not stock D rods so if there wrist pins are 19mm what are our's

[MessyHonda]

i have looked or 83mm b pistons but havent found shit :(


i think they are .080 over that equals 83mm

[rjudgey]

I'm pretty sure there 20mm but maybe U.K. spec engines might be different like the B20A rods our pins are smaller but yours are bigger for some strange reason?
The Rod bolts on stock rods are very strong i've never had one fail and i've even used ones that have allready done 60k plus miles and revved them to 8k rpm, and even when i had two conrods fail and they were getting stuck in the block they just mashed there way through the block without fail i'd say there easily as good as ARP although ARP are cheaper to replace than buying new honda ones!!

I'll try and measure one of my spare rods tonight to check the pin size.

[ZackieDarko]

i think they are 19mm (A20's)..could be wrong

[rjudgey]

If you look at Wisco or JE websites they ahve B18 pistons listed at 83mm

[ZackieDarko]

If you look at Wisco or JE websites they ahve B18 pistons listed at 83mm


so is .20 or .40 83mm for b-series pistons?

Wisco makes 81 and 82mm but they have them in .20 and .40 over

JE makes 83mm pistons part #242879

A20A3 bore/stroke is 82.7mm bore/3.58in stroke

the JE pistons say they are 83mm bore/3.047in stroke

wouldnt this reduce our CR?

[cygnus x-1]

Ghetto, with a mild performance build the stock rods will be fine. It doesn't make much sense to upgrade the rods if you aren't upgrading pistons as well.

C|

[hondaman1986]

I'm pretty sure there 20mm but maybe U.K. spec engines might be different like the B20A rods our pins are smaller but yours are bigger for some strange reason?
The Rod bolts on stock rods are very strong i've never had one fail and i've even used ones that have allready done 60k plus miles and revved them to 8k rpm, and even when i had two conrods fail and they were getting stuck in the block they just mashed there way through the block without fail i'd say there easily as good as ARP although ARP are cheaper to replace than buying new honda ones!!
I'll try and measure one of my spare rods tonight to check the pin size.


i would be thankfull if you would check them

[hondaman1986]

ok this is for anyone wondering why I posted this thread...

I am planing on running a high rpm N/A a20 8000+rpm to use at my local track.

im hoping to make 200hp N/A and have the support to do it. but it will take time... also with any luck i will not be running any power adders exept nitrous for the little extra boost out of a corner. I will be running dual weber dcoe 45's for my induction and a strait pipe out just behind the front tires for the exhaust. mods to the engine are yet to be determined as i will be testing combonations for the best power and power band.


ok i think that covers it. lol

so all i need to know now is our wrist pin size for the a20.


thanks for all the interest

[bobafett]

just to clarify

a20 uses a 20mm wrist pin NOT 19mm
also, D series are some of the worst rods ever. if u are too cheap to buy eagle rods then don't bother trying to make power na lol, eagles are cheap, and they work juuuust fine. :) sure you can get lighter ones, and if you are going all out NA, that might be a good idea. but if you just want your setup to hold together at 8000, rods probably won't be what fails first if u get eagle h-beams. :)

and you all know what my opinion is on pistons lol...

[bobafett]

Ghetto, with a mild performance build the stock rods will be fine. It doesn't make much sense to upgrade the rods if you aren't upgrading pistons as well.

C|

I agree, but it doesn't make sense to build a high rpm NA motor without upgrading both your bottom end, and building a bulletproof valvetrain. what good is a balanced bottom end that can hold 9500rpm if you head explodes?

stock parts are for stock motors, and powerful na motors are about as far from stock as they can get.

[hondaman1986]

just to clarify

a20 uses a 20mm wrist pin NOT 19mm
also, D series are some of the worst rods ever. if u are too cheap to buy eagle rods then don't bother trying to make power na lol, eagles are cheap, and they work juuuust fine. :) sure you can get lighter ones, and if you are going all out NA, that might be a good idea. but if you just want your setup to hold together at 8000, rods probably won't be what fails first if u get eagle h-beams. :)

and you all know what my opinion is on pistons lol...


ok boba i will be using eagle rods im not stupid enough to use stock d's or a's. from the begining i was saying that i was going to use eagle rods and was just wondering what our wrist pins were.

so thank you boba for the info i was looking for from the begining... 20mm yay i finaly have the answer lol

[bobafett]

well it looked like some people were looking at D stuff. :) we both know it would be a shame to use stock D rods just cause they would fit (and I doubt they do) thinking that it would be an improvement.

i know you didn't have your set on D stuff, but if your going to buy aftermarket, whatever suits the needs best. (ie lighter, stronger, whatever you need).

good luck with the build, what is your plan for pistons again?

[hondaman1986]

well it looked like some people were looking at D stuff. :) we both know it would be a shame to use stock D rods just cause they would fit (and I doubt they do) thinking that it would be an improvement.

i know you didn't have your set on D stuff, but if your going to buy aftermarket, whatever suits the needs best. (ie lighter, stronger, whatever you need).

good luck with the build, what is your plan for pistons again?


for pistons they will have to be custom forged. unless i can find (i doubt it) some 83mm b18a/b pistons. the reson the d rods where brought up was from the eagle web site. they are the same length and weight as the b rods but with a smaller wrist pins. they would be eagle of course. but now that i know our wrist pin size i will just get custom pistons made if i cant find any b rods

[AccordEpicenter]

youre gonna need alot of parts to support 8000rpm reliably. Id say for those rpms that youre gonna need a good set of aftermarket rods with forged pistons and some kind of upgraded valvetrain to handle that.

[hondaman1986]

youre gonna need alot of parts to support 8000rpm reliably. Id say for those rpms that youre gonna need a good set of aftermarket rods with forged pistons and some kind of upgraded valvetrain to handle that.

yep and a lot of time too

[hondaman1986]

ok yea i know this is a double post but for people looking for new pistons i may have found some for you.

http://cppistons.com/catalogs/sport_compact/sport_compact.html

they have b18c pistons that have close to the same bore as the a20 and if you use aftermarket rods they should fit. or you can have customs made

[ZackieDarko]

the problem with using B-series pistons is that well nobody has yet to try it

also the valve reliefs (sp) are different and nobody knows how that would work with our head

[hondaman1986]

the problem with using B-series pistons is that well nobody has yet to try it
also the valve reliefs (sp) are different and nobody knows how that would work with our head

yea i sent them an email asking them what the dome is on the pistons.

even if it doesnt work it gives you the basic dimentions to have someone custom build them for you too

also when i hit the yard again to pick up another a20 ill grab some b18 pistons and see what its like

[cygnus x-1]

I agree, but it doesn't make sense to build a high rpm NA motor without upgrading both your bottom end, and building a bulletproof valvetrain. what good is a balanced bottom end that can hold 9500rpm if you head explodes?
stock parts are for stock motors, and powerful na motors are about as far from stock as they can get.

Absolutely. I was only addressing Getto's question about a mild performance build though. Hondaman's build is totally different. And we should stop hijacking his thread. LOL! :lol:

C|

[ghettogeddy]

Absolutely. I was only addressing Getto's question about a mild performance build though. Hondaman's build is totally different. And we should stop hijacking his thread. LOL! :lol:

C|
well aas long as we keep it on topic its better than me starting another thread about the same thing lol , but im only looking for about 150hp tops so stock pistions in a .50mm bore should be ok rght and stock rods

[hondaman1986]

Absolutely. I was only addressing Getto's question about a mild performance build though. Hondaman's build is totally different. And we should stop hijacking his thread. LOL! :lol:

C|


yea you can highjack it now lol i got the info i needed

[rjudgey]

For a 150bhp build just use balanced stock rods, with stock honda bolts, have a rev limiter to 7k rpm, only use Honda A20A3/4 pistons with the 9.4:1 CR ratio with a bit of head skimming and block decking you should be able to bump this upto 10:1. Don't use patent pistons none of them have the correct placement of the valve pockets and all have the lower compression dish in the crown great ofr boost bad for N/A. If you can get the oversizes in Honda pistons great just go for the biggest size they do but any size thats bigger than current bore will do just so that you can have the block re-bored to make sure it's true. Then have oversized rings ordered and gap them by hand, make sure to get the pistons balanced as well, if sticking to 7000rpm i wouldn't waist money on getting crank balanced as if it is in good nick and doesn't need grinding the honda balancing is spot on from factory, just get the flywheel and pressure plate balanced together job done. If you were plannign on 8k rpm or more then you would have to have the whole thing done to perfection and with it asemsbled but for a mild build with 7krpm limit you'll be okay doing this way which is a lot cheaper!!! As far as a cam goes sticking with a 260-275 degree with 10-11 mm lift would be perfect for this setup no more is needed and would be a waist. Only thing i would upgrade is maybe change the valve springs from ET/A18 prelude on the inlets leave the exhausts the same, if you have the time and bit more money have bigger valves put in as well will make hitting 150bhp a piece of cake.

For Hondaman hitting 200bhp wth 8k rpm limit you will need rods i'd recommend the titanium Eagle rods for B18 LS and then the 83mm pistons just ask JE for blank crown and then have a good engine engineer do the pockets, you want the crowns flat preferably as this gives the best results, just shave the head 1-1.5mm and deck the block .5mm and have the chambers matched perfectly to the bores. You'll need lots of headwork to chambers and exhaust ports, some work on the inlets around the guide and the direct injection ports to weld them up and grind them flat with the port roof, 5 angle seats with 1mm inlet seats and 1.5mm exhaust seat get the seats radiused if possible and you will need larger valves to make 200bhp plus will be a struggle to hit that if you don't, don't mess around fit the biggest you can 33mm inlet and 37-38mm exhaust you'll need a custom header made or modifiy or S&S or Paceshitter get rid of the 2" main pipe they have and replace with 2.25" with mandrel bent 2.25" system or 2.5" system. Camshaft wise i'd look at 280-290 degree inlet with 11mm lift and exhaust with 290-300 duration and 11-12mm lift (12mm might need some slight modding with valve platforms). As far as the valve train goes as long as you upgrade the guides to bronze ones you'll have a solid setup, the valve train can withstand 8k rpm without any issues only thing to change would be springs from A18/ET prelude or if your using exhaust valves converted to inlet valves use the double springs of the Prelude exhuast valves all the way round or at least the inner spring from carbed prelude and the outer spring from A20A3/4 then you'll be okay. You'll also have to mod the webers as well if you want a hand with the mods and the jetting send me an e-mail, clutchnet flywheel and clutch kit to finish it off with probably best bet is teg hybrid gearbox mod to get the acceleration and make use of the higher revs. Any more advice or probs let me know and drop us an e-mail.

[Estimated Prophet]

For a 150bhp build just use balanced stock rods, with stock honda bolts, have a rev limiter to 7k rpm, only use Honda A20A3/4 pistons with the 9.4:1 CR ratio with a bit of head skimming and block decking you should be able to bump this upto 10:1. Don't use patent pistons none of them have the correct placement of the valve pockets and all have the lower compression dish in the crown great ofr boost bad for N/A. If you can get the oversizes in Honda pistons great just go for the biggest size they do but any size thats bigger than current bore will do just so that you can have the block re-bored to make sure it's true. Then have oversized rings ordered and gap them by hand, make sure to get the pistons balanced as well, if sticking to 7000rpm i wouldn't waist money on getting crank balanced as if it is in good nick and doesn't need grinding the honda balancing is spot on from factory, just get the flywheel and pressure plate balanced together job done. If you were plannign on 8k rpm or more then you would have to have the whole thing done to perfection and with it asemsbled but for a mild build with 7krpm limit you'll be okay doing this way which is a lot cheaper!!! As far as a cam goes sticking with a 260-275 degree with 10-11 mm lift would be perfect for this setup no more is needed and would be a waist. Only thing i would upgrade is maybe change the valve springs from ET/A18 prelude on the inlets leave the exhausts the same, if you have the time and bit more money have bigger valves put in as well will make hitting 150bhp a piece of cake.


I love you.

[hondaman1986]

For a 150bhp build just use balanced stock rods, with stock honda bolts, have a rev limiter to 7k rpm, only use Honda A20A3/4 pistons with the 9.4:1 CR ratio with a bit of head skimming and block decking you should be able to bump this upto 10:1. Don't use patent pistons none of them have the correct placement of the valve pockets and all have the lower compression dish in the crown great ofr boost bad for N/A. If you can get the oversizes in Honda pistons great just go for the biggest size they do but any size thats bigger than current bore will do just so that you can have the block re-bored to make sure it's true. Then have oversized rings ordered and gap them by hand, make sure to get the pistons balanced as well, if sticking to 7000rpm i wouldn't waist money on getting crank balanced as if it is in good nick and doesn't need grinding the honda balancing is spot on from factory, just get the flywheel and pressure plate balanced together job done. If you were plannign on 8k rpm or more then you would have to have the whole thing done to perfection and with it asemsbled but for a mild build with 7krpm limit you'll be okay doing this way which is a lot cheaper!!! As far as a cam goes sticking with a 260-275 degree with 10-11 mm lift would be perfect for this setup no more is needed and would be a waist. Only thing i would upgrade is maybe change the valve springs from ET/A18 prelude on the inlets leave the exhausts the same, if you have the time and bit more money have bigger valves put in as well will make hitting 150bhp a piece of cake.
For Hondaman hitting 200bhp wth 8k rpm limit you will need rods i'd recommend the titanium Eagle rods for B18 LS and then the 83mm pistons just ask JE for blank crown and then have a good engine engineer do the pockets, you want the crowns flat preferably as this gives the best results, just shave the head 1-1.5mm and deck the block .5mm and have the chambers matched perfectly to the bores. You'll need lots of headwork to chambers and exhaust ports, some work on the inlets around the guide and the direct injection ports to weld them up and grind them flat with the port roof, 5 angle seats with 1mm inlet seats and 1.5mm exhaust seat get the seats radiused if possible and you will need larger valves to make 200bhp plus will be a struggle to hit that if you don't, don't mess around fit the biggest you can 33mm inlet and 37-38mm exhaust you'll need a custom header made or modifiy or S&S or Paceshitter get rid of the 2" main pipe they have and replace with 2.25" with mandrel bent 2.25" system or 2.5" system. Camshaft wise i'd look at 280-290 degree inlet with 11mm lift and exhaust with 290-300 duration and 11-12mm lift (12mm might need some slight modding with valve platforms). As far as the valve train goes as long as you upgrade the guides to bronze ones you'll have a solid setup, the valve train can withstand 8k rpm without any issues only thing to change would be springs from A18/ET prelude or if your using exhaust valves converted to inlet valves use the double springs of the Prelude exhuast valves all the way round or at least the inner spring from carbed prelude and the outer spring from A20A3/4 then you'll be okay. You'll also have to mod the webers as well if you want a hand with the mods and the jetting send me an e-mail, clutchnet flywheel and clutch kit to finish it off with probably best bet is teg hybrid gearbox mod to get the acceleration and make use of the higher revs. Any more advice or probs let me know and drop us an e-mail.


hey thanks vary much for the input i will always take advice. 8000+rpm is my goal but 7000 is more than enough. also remember that i will be useing a small shot of nitrous to get to my 200 hp mark.

[rjudgey]

You won't need Nitrous this way ;0) 200bhp is piece of cake with Higher CR ratio, and bigger valves especially with twin webers i'd prepare your gearbox for more like 250bhp if you plan on NOS but don't forget you need to try and use something to add more fuel when the NOS kicks in maybe a turbo carb fuel pressure regulator might do not sure i'm sure someone whill have something getting NOS setup properly on carbs i ahve seen kits for DCOE's so must be something out there.

[rjudgey]

Just checked U.K. ET/A18/A20 rod specs 137mm length with 20mm piston pin

[hondaman1986]

You won't need Nitrous this way ;0) 200bhp is piece of cake with Higher CR ratio, and bigger valves especially with twin webers i'd prepare your gearbox for more like 250bhp if you plan on NOS but don't forget you need to try and use something to add more fuel when the NOS kicks in maybe a turbo carb fuel pressure regulator might do not sure i'm sure someone whill have something getting NOS setup properly on carbs i ahve seen kits for DCOE's so must be something out there.


they have direct port kits that inject nitrous and fuel. thats what im gonna use.

they also have there own fuel pressure kits to use with standard carbs and nos systems for the added fuel needed with the wet systems. if someone made a a to b trans adapter plate that would take care of the trans prob. hell i might make one if i get lucky and have the tools. lol "IF".

[ghettogeddy]

For a 150bhp build just use balanced stock rods, with stock honda bolts, have a rev limiter to 7k rpm, only use Honda A20A3/4 pistons with the 9.4:1 CR ratio with a bit of head skimming and block decking you should be able to bump this upto 10:1. Don't use patent pistons none of them have the correct placement of the valve pockets and all have the lower compression dish in the crown great ofr boost bad for N/A. If you can get the oversizes in Honda pistons great just go for the biggest size they do but any size thats bigger than current bore will do just so that you can have the block re-bored to make sure it's true. Then have oversized rings ordered and gap them by hand, make sure to get the pistons balanced as well, if sticking to 7000rpm i wouldn't waist money on getting crank balanced as if it is in good nick and doesn't need grinding the honda balancing is spot on from factory, just get the flywheel and pressure plate balanced together job done. If you were plannign on 8k rpm or more then you would have to have the whole thing done to perfection and with it asemsbled but for a mild build with 7krpm limit you'll be okay doing this way which is a lot cheaper!!! As far as a cam goes sticking with a 260-275 degree with 10-11 mm lift would be perfect for this setup no more is needed and would be a waist. Only thing i would upgrade is maybe change the valve springs from ET/A18 prelude on the inlets leave the exhausts the same, if you have the time and bit more money have bigger valves put in as well will make hitting 150bhp a piece of cake.
For Hondaman hitting 200bhp wth 8k rpm limit you will need rods i'd recommend the titanium Eagle rods for B18 LS and then the 83mm pistons just ask JE for blank crown and then have a good engine engineer do the pockets, you want the crowns flat preferably as this gives the best results, just shave the head 1-1.5mm and deck the block .5mm and have the chambers matched perfectly to the bores. You'll need lots of headwork to chambers and exhaust ports, some work on the inlets around the guide and the direct injection ports to weld them up and grind them flat with the port roof, 5 angle seats with 1mm inlet seats and 1.5mm exhaust seat get the seats radiused if possible and you will need larger valves to make 200bhp plus will be a struggle to hit that if you don't, don't mess around fit the biggest you can 33mm inlet and 37-38mm exhaust you'll need a custom header made or modifiy or S&S or Paceshitter get rid of the 2" main pipe they have and replace with 2.25" with mandrel bent 2.25" system or 2.5" system. Camshaft wise i'd look at 280-290 degree inlet with 11mm lift and exhaust with 290-300 duration and 11-12mm lift (12mm might need some slight modding with valve platforms). As far as the valve train goes as long as you upgrade the guides to bronze ones you'll have a solid setup, the valve train can withstand 8k rpm without any issues only thing to change would be springs from A18/ET prelude or if your using exhaust valves converted to inlet valves use the double springs of the Prelude exhuast valves all the way round or at least the inner spring from carbed prelude and the outer spring from A20A3/4 then you'll be okay. You'll also have to mod the webers as well if you want a hand with the mods and the jetting send me an e-mail, clutchnet flywheel and clutch kit to finish it off with probably best bet is teg hybrid gearbox mod to get the acceleration and make use of the higher revs. Any more advice or probs let me know and drop us an e-mail.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=014&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=330107960904&rd=1,1#ebayphotohosting
so will these pistons be ok

[newaccorddriver]

Fonly use Honda A20A3/4 pistons with the 9.4:1 CR ratio with a bit of head skimming and block decking you should be able to bump this upto 10:1. Don't use patent pistons none of them have the correct placement of the valve pockets and all have the lower compression dish in the crown great ofr boost bad for N/A.


right now, for my build, im using aftermarket replacement pistons. they have PJO and 0.50 on them. as far as im aware, these pistons are made specifically for my engine arent they? i figured the PJO portion would be proof enough that they were made for it just like some of them have P75 and other ECU codes

[bobafett]

my stock pistons said pj0, but I dont recall if they had any other numbers. .050 is a pretty huge overbore (same as on my motor), so they would definitely be aftermarket pistons. :)

You can always compare them to a stock piston if you have one lying around...

[MessyHonda]

my stock pistons said pj0, but I dont recall if they had any other numbers. .050 is a pretty huge overbore (same as on my motor), so they would definitely be aftermarket pistons. :)

You can always compare them to a stock piston if you have one lying around...



how much did your pistons run you?

[rjudgey]

I've seen patent oem pistons with PJ0 stamped in them they were still sealed power ones made by one of the ghetto mexican factory's under another name. Unless you have bored your block out allready to .50 don't use them and get the Honda ones with a smaller over bore the decrease in bore size will only help you maintain reliability and if you wear them out then you can use your .50 pistons as a last resort to re-build that engine. Only way is custom forged or Stock Honda if planning NOS and 200bhp with revving over 7k rpm you really need forged cast ones won't last long about 15k miles i know as i have to change them every 15k miles as they warp trap the rings and then crack along the top of the crown untill it blows a big hole through the top. You can try them upto you but i wouldn't advise it unless you plan on building another engine up straight after with better parts.

[newaccorddriver]

my stock pistons said pj0, but I dont recall if they had any other numbers. .050 is a pretty huge overbore (same as on my motor), so they would definitely be aftermarket pistons. :)

You can always compare them to a stock piston if you have one lying around...

my block is bored 0.020. i believe its 0.5mm.

as far as piston talks go. this is a typical rebuild which ill be boosting and blowing soon. my spare block will be recieving special treatment AKA forged pistons and rods.

[rjudgey]

If your running a cam make sure the valve reliefs are remachined to the right place other than that they should be fine. Also give them an extra .05mm clearance than recommended so they can expand more from extra heat, but still gap the rings by hand though

[cygnus x-1]

Just some things I learned about pistons and sizes when I was looking for pistons. Honda only makes two sizes of A20 pistons; standard (82.7mm) and 0.3mm oversize (83mm). The non-Honda replacement pistons have a larger range, usually standard, 0.5mm over, 0.75mm over, and 1.0mm over. Notice these are all metric measurements. The corresponding imperial sizes would be (roughly):

mm oversize : inch oversize
0.5mm : 0.020in
0.75mm : 0.030in
1.0mm : 0.040in

C|

[ghettogeddy]

well i found a set in .50mm also what are the gains from a bore with larher pistons

[newaccorddriver]

well i found a set in .50mm also what are the gains from a bore with larher pistons

0.5mm is what i have according to cygnus x-1's chart there. the gains are very minimal in stock form. perhaps maybe about 10hp or so if its an all out build? rjudgey can correct me if im wrong since hes built so many of these things

[rjudgey]

you won't see any noticeable gain it's not worth it also at that size you'll start running into head gasket sealing problems so make sure the Felpro head gasket yoru using has enough space for that size piston.

[AccordEpicenter]

yea dont go huge on bore it does weaken the block a little, there are better ways to make power

[tuxdreamerx]

Damn I have mine bored 0.050 over lol I havd a piston lose a chunk in one cylender so that bore was required. but I have hella power

[TWOLOUDNPROUD]

Back from the dead.