Swap - ET2 / A18 / B20A (JDM) / B20A5 / B21A : Head - A20A : Block

[Justin86]

The does make since, but even if you can't use the full benefits of the VTEC head the fact the you have one is reason enough to do it. Saying that it is possible to make the switch.

Well it looks close but I don't see any big machine work so I guess this is pretty much bolt on?

[Low Tek]

this is a question for sean or kms - I am wanting to do a new cam, but I want the higher rpm range... I want something like 9grand for the new red line.. and I want it to be an agressive pull for street/strip..
I am goint o run the stock a20 block and head - boring it out 40 over and then resleeving it, I have the b16 intake manifold, and a 87 prelude distributer/ecu and a 20 psi t3 turbo.. I have done some research, but I need the cam to pull it all off

you guys both seem to know what you are talking about, so what do you think??

oh yea.. and what compression should I run to get the hard 20psi hit??

thanks

[Vanilla Sky]

he needs a head that he can cut apart and see how much room is in there... i've tried to sorce one, but the only ones i found were either trashed (severely) or would only be sold with the rest of the running engine...

he also thinks that this is not a needed swap, that you can make the same power using some common sense with upgrading the a20... talk to him for more details... andy says he's looking to be into the 14's in his 2gee wiht the a20a1 and some other mods... i'm looking into getting a JDM b20a and modding it in the same manner as sean suggests the a20 be modded... he has gotten me into looking for a frame for my car because i have learned that i can do something with the motor i already have (i refuse to drop in a POS a20a1 without modding it any[it runs just fine])

dammit... sorry for the long post, i was just hoping to help with some info since it seems to be something that may be done widely, even though most are on tight budgets

[1988starter]

First off you can onle bore 30 over or you will have too thin walls.. Second 9000 redline go buy an s2000 because A20A1 has about what the max you should go and that is 7500 adn for 20 PSI no more than 8.5 is my guess

[buzzbomber88lx]

i wouldnt drive long distances because of compression reasons from the decreased flow rate. Like when you put 289v8 heads on a 302 it reduces flow but enhances compression. putting 351w heads on a 302 gives it more flow but a little less compression. the smaller the head the greater the compression. going down from an a20 to a b16 is asking for trouble i'd say unless you are only making quarter mile passes and dont want a daily driver. just my .02
-Ryan

damnit....brings back mameries of my dads pimpin 90 lude b21a1 with 4ws and an si. nice job getting that all done. should be hella faster.
pogi is right. turbo is an easy way and actually pretty cheap way to get performance. but nitrous is the cheapest and safest on the motor.

[phrenology]

I have a quick inquiry, sorry if I'm not up on the tech curve with you G3 Accords, but I'm doing the best with what I got. I have a G2 1984 Accord Hatchback LX. I love my car, the body and undercarridge is in excellent shape. I want to give it a new lease on life but I'm working on a shoe string budget. I'm trying to get 120 HP into it. The original motor has 160k miles and only gives a meager 86 rated HP. I'm about ready to rip that ES2 out. I need some advice on an engine swap that will be cheap and require little or no modifications. Will an ES2 manual 5 speed tranny fit with an A20A and will it take the torque? Anyone have torque ratings? This maybe a stupid question but will a B20A DOHC head bolt up to a A20A block? If you know anyone who has done a similar swap with a G2 Accord can you let me know. I need to know engine mount matchups and engine bay clearances for the motors. Whatever motor I swap to I'm using a pair of Weber DCOEs to power it. I only want to have to build one intake manifold for one engine. My biggest concern is that the G2 Accord is about 3" narrow wheel to wheel distance when compared with a G3 Accord. If I switch engines/trannies will I have to get special CV joints to keep the wheels clear? Any help or sugeestions would be much appreciated. Email me with comments: [email protected]

I have an 84 Accord LX Hatchback and I'm planning on going with an A20 engine swap. I have a pair of Weber DCOE 40s to power it, and I'm ready to toss out my ES2 1.8 Cvcc engine. I'm just trying to get the most aftermarket compatible and reasonable to install engine to swap into my ride. I've been told by many that my best bet is an A20. I'm interested to know if anyone has done an A20 swap with a modified head or if it is possible to mount a B20 DOHC head on an A20 block? I'm also concerned that putting too much power on my current stock manual tranny will be too much torque for it to handle. Any suggestions? If I swap transmissions I will have a problem with CV joint distances. The G2 Accord is about 3" more narrow, measured middle tire to tire than the G3 Accords. Help!

[Tref_LXI]

i dont know about a lot of the questions you asked, but these are the stats for the a20a3 which should fit in your car, 120 hp/122 torque at 3000rpms, so its a very good engine because it reaches its max torque very fast.

[Mike's89AccordLX]

Um... think you'd be fine with SOHC with dual 40's. I don't think you will gain too much with a head swap but hey I don't know too much about head swaps.

I'm shocked b/c I didn't know that b18's had carbs. I think that's awesome though.

[CARBurn]

Phydeaux could help you there, he took an 2nd generation Accord hatchback and mounted an 88-89 a20a3 motor with DCOE's. He also helped me with my weber installation on my 87 Accord. He very knowledgeable about the weber conversion in our Accords.

That B20 head on A20 block question has been posed before, I thought the findings were this is not possible, am I right anyone?

If you want to go DOHC, there is always the B18A, it's a dual carburetor and makes 130 hp and 119 ft-lbs of torque, I planning on beginning this swap on in the summer. The only drawback is aftermarket support which I know you are looking for as well, but I am currently attempting to remedy that by trying to contact some import suppliers.

[89LXIHATCH]

my friend was telling me i could put a prelude 2.0 si head and computer on my car and i im ready to port, polish, and grind my injectors and if i could get this head for my car over working on the stock head from a junkyard cause my head is done but yea would it work or would it not bolt up is the question and do you think their might be any other compliactions thanks.

[Jareds 89 LX-i]

Well it all depends on which year Prelude you're talking about. If it's 2nd gen Si, then it has the same A20 as our 3geez, but if it's the 3rd gen Si, then it has the DOHC B20. Of course the A20 head would swap cuz it's the same engine, but I doubt the B20 head would be swappable. You never know until you try though... just need a guinea pig!

Originally posted by 3rdGenFanatic
Hey Jared, out of that lineup, which car is yours. I'm looking at those clear corners... o.0

Mine is the completely stock one on the far left. The one with the clear sidemarkers belongs to Rooz (SiR)

[3rdGenFanatic]

Hey Jared, out of that lineup, which car is yours. I'm looking at those clear corners... o.0

[Brettmans5]

figure if the prelude DOHC head bolted up to a a20 block there would be a lot of accord running around with that already done , but hey it is worth a try, if it works there will be a run on DOHC heads from b20's.

[nvrenf]

sound kewl any info on a 93-94 del sol single cam vteck head on a a20a

i got a b18c5 head onmy girls civc 18ls block i use nos switch to activate, them both (nos and VTECH)

[gofast]

guys i'll show more later the two heads pic. is a n a20a head beside an b21a head you can have a b21a head fix to fit an a20a block more soon
heres some more info for you guys to have head welded up it cost me 40.00$ & to shave it ti was 30.00$
the bottom timing gear you have to use is the b20a one i'm having to have it shimmed to fit the a20a crank
i'll post a pic of both heads one welded and one thats not welded
how i did this by placing an a20a headgasket on a b20a head
well the heads im using is a b20a .
im puting it on an a20a and for not much money
im going to use a distributer out of a 1987 integra
i think dose any have any info
perlude
idon t have a com . on line right now . so i use the neighbor 's com
slow BUT REAL!!!! so when i can i do OK. i'm sorry about the spelling
more pic.http://images.cardomain.com/member_i.../284796_13.jpg
that pic. sucks on car domain the pic can be enlarged
its so much better. i did not use a metal head gasket. i sent the head to the machine shop with a head gasket they welded head
to match more later sorry
IT RUNS !!!!!!!!!!!!! and damm good
my computer has been down
i'll post more pictures tomorrow. the motor is in the car now.
i'll try . i'm having timing belt problems . i can't find one the right size
who will post some picfor me
i ll send them tomorrow some time ok ? please reply
heres a list of parts i used in my motor
block A20A3
head B21A3
intake B21A3
exhaust B21A3
cam s B21A3
camgears B21A3
timing gear on the crank B21A3 ****
distributer B16
cranksensor B16
now . the bottom timing gear needed to be shimed to fit the A20A3 crank
its in my car and running now
ok there they are ill get more later
i like your lude . i have an 87si
the reason for the shim in the bottom timing gear is the a20a crank is smaller in diameter
i have another B20A3 head
it runs good i let a machine shop make the shim.
they used brass
pogi lxi
i spent a whole year or more try to get this motor to work!
just tell me where you live 'i'll drive it right over. while i'm there i'll
anwser all your clutch pedal & cable questions!!!

if you ask any motor builder the head is where the HP. is
if you look at all the engine specification charts in the chiltons
book. the b21 has the most HP for a non v-tec inline 4 honda
the two heads when compared are so close to each other .
why not?
now with my car im still tuning it pulls real hard from 4000 to 7200 . i think that my crank sensor is retarded to much.
i need to thank all you guy here. with out ya' ll iprobably wouldn't
run now
i live right next to bristol drag way . in the spring i ll run at thursday night street fight . i don't think i know of a dyno. around here.
im righting it up now. it will be ready later this week pic. and all
now my car the first timming belt i use broke well it bent every
valve in it . i have another set of valves . ill change them soon
heres some more info.
what needs to be welded up on the B21 head? If you take an A20 head gasket and place it on an B21 head you should be able to see what needs to welded up its not much at all. i have some pic. at cardomain and i still dont know how to get then here.
know lets talk about the thing that i had to do that i didn't think about but i found out as i whent along
there's an oil jet in the a20 and b21 the oil jet in the b21 is level with the block.
the oil jet in the a20 sticks out of block about 1/8" of an inch. the a20 head has a place for it . the b21 head dosen't . the oil jet in the a20 is made of aluminum so i ground it off level with the block.
hey check this out

you guys want more?
timing gear
if you look at the A20 or B21 bottom timing gear you will see that they both have keyway made into them. A20 has smaller crank diameter then the B21. to make the shim they had to remove the keyway notch and then they made the shim out of brass. after the shim was in place they cut a notch through the shim and into the gear. they also gave me some key stock to use.
intake
the intake is B21 so it fit the head.i had to adapt my vac. lines to that intake .if you need help there i just winged it. there's alot of stuff on the B21 intake that MY 86-87 FI. doesn't use ,if you have 88-89 FI it would work better.
lets try some pic
HAHAHA!!!


i just don't get it ?????
if it isn't a car i'm a dumbass.
the pic are cardomain . tell me what you need
see i'm a dumbass . i forgot the (at)in the last reply
nx racer
you cant make a link from cardomain.com?
nxracer
my cardomaim user name:cjs1234us
theres alot more on the other pages
nxracer
thank you if you post all of them it would help . and again thank you
i also have a turbo and im going to put boost on it one day.

[NXRacer]

this has already been tried before and it turned out to be a huge bitch and the project never was finished. I'd be interested in seeing if this actually worked and ran and how much trouble they had to go to to get it to work.
what did you have welded on a head?!?!?!?
DAMN, so does this mean we can have a DOHC motor w/out having to go through the headache of trying to locate a JDM Accord b20a motor?? that would TIGHT. MORE INFO DUDE!
?? not understading ya. are you using a DOHC head on an A20 block? if so, which head? I'm getting conflicing info in the thread.
thanks
Is that the JDM Accord B20a or the prelude b20a?
Either this guy is REALLY excited when he posts his progress or he can't spell worth sh*t.
No offense gofast cause you're doing something that a LOT of people are interested in, but you'll get a lot fewer questions if you take a little time to spell things out somewhat more understandable and put together.
Thanks for the R&D and keep the info coming!!

email me the pics at [email protected] and i'll post em up for ya
are the pictures you're trying to show available on your cardomain site for anybody to see? I dont think i can use the links you provided above. If you have them up on your cardomain site, then i could link them up here, but the ones you have now won't work.
next time PM me that info. I'd edit your post before you have a ton of people logging on to your site and getting you in trouble or something.
here are the pictures it shows the head is on, but that doesnt really show it works and runs.

I've never noticed a truly significant VTEC change-over except in the H22. That is one hell of an awesome change in sound!!!
Other than that, the H17, nope. Can't even tell when it's in VTEC or not. My friend's B16, nope. My friend's friend's B18C1, nope.

either both motors are bone-ass stock or you're just deaf.
you make some good points, but you gotta realize that theres more into it than just boring out the cylinders so it makes more CI. The ports on the head have to match the passages on the block. If it would be just as easy as boring out the block and slapping any head on it, this wouldnt really be an issue.
Even LS/VTEC's have their problems that make them unreliable. And those are a helluva lot closer then the A20/VTEC head combo.
F23a is OBDII which could cause a problem. It came in the 98-2000 accords and is VTEC.
A better option would probably be the F22a/b head from the earlier accords simply because they're OBD1 and will cause a LOT less headaches then trying to put a VTEC head on our motors.

I think I'll just stick with the complete A20 and just boost the hell out of it. :cool2:

thats my plan. why go to all the hassle for DOHC? not worth it IMO.

[pric]

The B21A had a large bore compared to the A20A and much larger than the B20A5. So I would expect that the valves will hit the cylinder wall.

[carotman]

I know someone that put a B20A3 head on a A18.... it worked but had coolant problems

I posted 1 year ago that someone installed a B20A3 head on an A18A... the problem was the cooling passages and the timing gear location. He said in the other thread the he shimmed the bottom gear... fine, I can beleive that.
However, the distributor and crank sensor are NOT from a B16A... they are from a D16 (Integra 86-87 engine)
The major problem I see with this setup is that you need a custom intake manifold to make it work... or a monster hood
Like sean said, for all the trouble involved, you could use a VTEC head instead... no need for a custom intake with that head since the engine leans in the proper way.
Nice work tough... I wonder if it actually runs.

A20A4...my head sux.. but why the each piston of this engine has four cuts for valves?

That's because of the exhaust valve location isn't at the same place on cylinder #1-2 and #3-4. This way honda can make only 1 model of piston instead of making 2 different pistons for the same engine...
The F23A head isn't bad but I would prefer to have the DOHC F22B head on it. Interesting project tough.
It sure seems to line up properly.
Once the head is bolted to the engine, the rest would be fairly easy.
However, the JDM B20A head would be a better option to mod in my opinion. The intake manifold wouldn't need to be modified to fit in the car since the B20A uses the same mani as the A20A.
The problem is findind a B20A head in North America, which leaves us back to square 1.
With the B20A5/B21 head, you would need to mod the intake mani so it fits inside the enginebay. Just a cut N weld thing.
I would run the PK2 ecu with that setup but the PJ0 could also run it.
For the Manifold, I was refering to the Accord B20A. The Accord B20A will not bolt to the B21A or 88+ Prelude B20A
The A20A has a 82,5mm bore if I remember.

[bobafett]

hmm this is pretty interesting. if you are using the prelude head then there will be some parts we can buy, this is pretty cool..
youve definetly got my attention

why not just bolt on a k20 head instead, its probably just as feasable.. lol...
fuggitaboutit guys.....
interesting. doesnt seem that close to me... but with enough work, who knows...
what vehicles did the f23a come in ?

good question, i would say for balance or equal compresion. mabie plug clearance?

spark plugs go in the head man, not the block
lol
b20 spark plugs go into the center, through the valve cover, a20 spark plugs go in through the side, through the head. but they are both in the head.

[PogiLXI]

I think Hes Welded an Metal headgasket on it, The ones people use to lower compression on Turbo Cars. Actualy I have no clue just giving out what I think.
I think the metal head gasket is the only way to go, cause the usual one will just Fall apart if trying to mate To difrent of passages, what do you all think???
I really thing the Metal head Gasket Is the way to go, What do you all think???
What did they Weld?
Bboi, u a Flip? I am, Phillipino. Thus the Pogi, Errr Pheneticly Poogie. heh, but yah.
Gofast! What Language do you speak? this dude must be a joke, Cause A person that cant Type or Spell, Sending a head off to a shop and say Weld, just doesnt add up. I HIGHLY DOUBT this is going to work, and you just spent money on NOTHING, I say BOOOOOOO!!!!! BOOOOO!!!!
88LXI DSM turbo there pritty much interchangable with Everything, only thing I think that has a pripority (I dont know how to spell that word) turbo is Sabb. now if it had DSM BLOCK with VTEC heads, NOW THATS NUTZ! Mitsu should come out with a VTEC type head, Would DEFNENTLY get its Boost in Sales, Turbo VTEC 2.0 From the FACTORY! oh shit, Ill be at the Dealership in a heartbeat. Also Mitsu has that AWD TURBO! honda Cant hang with a Mitsu, It would beat it in so many Catigorys STOCK.
Bah, There the worse though, Trannys Go on them all the time.
Back to the subject, I would Defnently like to do a head swap, if It isnt that Expensive, and its not problematic.
ztec, hahahahahahaha. I hate Fords. Ima Chevy man my self. Im build up a Chevelle 454 Twin Turbo FI, I like Superchargers, but Its been done so many times, Ive searched the internet for Turbo Kits for hotrods, and came up with nothing, I found Alot of Buick GN stuff. I can maybe mate GN stuff to a 454, mostly electronics.
anyway. WHATS GOIN ON WITH THIS HEAD THING!?!?!?!
Gofast Probly hasnt Come back to this thread, cause he Knows that it Doesnt Work!!!!

alright, there is STILL no proof this thing runs, for all we know Its just a head sitting on the block. need better pics, even a VID! gofast keep us updated.

peeps, for all we know, the head is just sitting on the motor, I still wont belive it till I get some better pics, even a Vid. Im hopeing for Gofast to prove me wrong. so Facking do it then!

[Rendon LX-i]

is there any other head that would fit the stock motor. kinda like a LSVTECH. u know just putting the vtech head on a ls. will i was thinking we could do something like that to. prolly a dum ass questions but tell me what u all think

so its gonna need serious work. so a b16a vtec head. thats cool

ok i guess that out of the storie and shit. does any one have there motor BORED OUT. if u did tell me what size did u bored it out to

[Justin86]

. You can put a B16A VTEC head on but it requires some serious work and it is not safe cause some place have to be machined so thin. Things will break.

Originally posted by bobafett
go down to radio shack, and ask for either the 900mhz or the 2.4ghz vtech headSETS, they should have some in stock. i dont know if it will add that much power, but you can get a power inverted and run them off your battery and convert to 120vac. im not sure how you are going to hook up a phone line into it since you are in your car, but i think its worth a shot... but again, im not sure on the horsepower gain of this mod...

Dude then my friend have VTECH in his Dodge van. That thing is pimp.

Sean is the one how tried to put on a B16A head on. I guess if you could get a cast iron head it should be able to withstand all the milling and stil be strong enough, but it would be cheaper to swap a B16A engine.

Originally posted by MoonScryer
OK, I'm going to add to this thread, but don't shoot the messenger. I was at the track last night, and a dude I know told me he knows of a car like mine, yes a 3rd gen, that has the SOHC V-TEC head from a 5th gen on it. I made sure he was talking about mine, and not a 4th gen, and he said yes. He is trying to put me in contact with the guy who has said engine. I don't know if he was giving me shit or not, but I will find out either way.
Now, go away.

Shit that would be cool. I though the VTEC heads were only DOHC. Well talk to this guy and hope for the best.
Well when my brother gets home I will do some measurements on his Accord to see how close the F22 head is to the A20.
But isn't the h22a DOHC. The point was to get a SOHC to have a better match up.

Originally posted by sixgears
Hey JUSTIN86....you have no clue. Sorry, but it's not an issue of strength. Very rarely is there a problem of strength in a head. And, a CAST IRON head....what the hell? The issue with swapping any head to any other block is five different things, others can be worked around easily. Borespacing, water jackets, oil passages(this one is fairly easily covered), bolt pattern and valve clearance. I'm not sure which of these is the issue in Sean's trials, but I will almost guarantee it is one of these.

Well Sean didn't really talk about the other things you mentioned, but I don't think that he would have spnet soo much time on this to have the oil passages not match up. From what he said that it would be a strength issue. Inorder to get everything to match up correct he had to machine the shit out of it. He said that there probably would be a strength issue with it.
I brought up the cast iron head cause they would be stronger then the aluminum. But unless you could get the cast for the head and have some Iron poured in, it is not really possible.
(forestales )

[bboipinoy112]

the head to the block ? lol .. this guy is funny .. he needs to explain everything he has/is doing .. CUMMON MAN ! we need a FULL explination . . . like maybe at least . . 8 lines ? haha .. that will be amuzing to all

Originally posted by PogiLXI
Bboi, u a Flip? I am, Phillipino. Thus the Pogi, Errr Pheneticly Poogie. heh, but yah.

yea im filipino .. hence the "PINOY" in my user name ..

[sixgears]

This is what's going on, from what I can tell. He had the rim of the combustion chamber welded to create a chamber whose edge will line up with the A20 head gasket, therefore also the bore of the A20 block. The head is then milled to create the flat surface it needs to have (welds protrude). Welding is common in 4-cyl oval racing to increase compression. What I can't figure out is that PhydeauX mentioned that the bore on the A20 is in fact larger than the B20's, so why would welding be utilized? GOFAST....first you said it was a B21 head, then said B20, so which is it? More info please.......

I'm bumping this back to the top so we can all figure out is up here.....this GOFAST guy gives us a little info that could possibly turn 3gee performance around and......laters. What, come on, you just don't do this. Sometimes I wonder about people.....

[smufguy]

well seems like its likely for someone to get a bashin if he does not respond on time or say somethin clearly. For example im from a third world country for heavens sake and i can make some sense
well the mixed and matched heads are in the B series category, not a B series head on a A20. so i dont know. Besides steve if u do a search or talk to our moderator Sean and Carotman to name a few, u will know that this project for the A20 has been attempted before.
yo pogi i was about to say what the heck ur talkin about mitsu cars and shit. anywho, like i said if u had been on this board for long, u would know the deal with the head jobs. and not to mention that the bmw 7 series has a variable intake runner length so thats the awsome shit.


Gofast, so technically its not a bolt on. Its something that can be "Made" to work with lots of changes and money spent for what? More than just pictures, i wanna know what good it does performance wise.

Originally posted by gofast
pogi lxi
i spent a whole year or more try to get this motor to work!
just tell me where you live 'i'll drive it right over. while i'm there i'll
anwser all your clutch pedal & cable questions!!!

I believe in your word. It does not mean i stand by it. BUt like i mentioned it before, I wanna know the money u spent on your project and the performance you gained from it. I wanna know how hard it was and the availability of the parts that you used. Cause sure are hell i dont know if i can find a B21 around my junk yard. But u cant escape from the cost/benifit ratio. so I wanna know how big our benifit is and more over the COST. So give us that and pics and/or estimated performance boost just from the head swap (no internal motor work) and it should speak for itself.
That is sick. Purely A fruit of hardwork and you got my respect buddy. You are going on my website pretty soon.
:super:
I wish you guys made just one thread for this. This topic has taken 3 threads (which are all over the place).
i know starter, i was just saying it would have been much easier to follow up if everything concerning one thing was in one place.
::: echos ::: still waiting for the numbers ...............
hehehe gofast, it was your hardwork man. It does not matter who helped you but you came up with the idea, u looked for parts, u researched it, u went thru with it. Congrats to you and cant wait to see the numbers its running on the dyno and on the strip.

Originally posted by NOAHS88accord
so to do this, i need the b21 head, b21 intake, b21 exhaust, b21 gears, and what else, what do I tell the machine shop, I need a how-to with pictures,
MR. GOFAST, please post what all is needed, what we have the shop do, and any more pictures you have. Also please do a step by step walkthrough of what you did to get it to work please.

heres a list of parts i used in my motor
block A20A3
head B21A3
intake B21A3
exhaust B21A3
cam s B21A3
camgears B21A3
timing gear on the crank B21A3 ****
distributer B16
cranksensor B16
thats all he posted. Have fun finding em.
IS there gonna be a write up on this?? Explaining how everything was put together?? It cant be just a bolt on is it??
How does this B21 head flow compared to our A20. I dont remember it being mentioned.
cool stuff. Its defenitely one mod that im gonna put it on my website with links and pics. Whooohoooooo baby, ::: gets goosebumps ::::

pogi is right. turbo is an easy way and actually pretty cheap way to get performance. but nitrous is the cheapest and safest on the motor.

I highly doubt Nitrous is the safest. Besides, its the cheapest way to make HP but not all the time and yet be legal. For me, performance is being a streetable car with kick ass performance, thats why Sean is #1 in my book right now. If anyone can do that with either a forced Induction or NA i will be appauled. But Nitrous is a no no for me and even tho it makes good hp, and since its not worth it for my motor and money, i would say its a waste of my money. But i know a lot of people on the board run Nitrous, atleast 5 or 6 that i know of, but its just aint my thang. :cool2:
The A20 manifold fits on the B20A. Dont try it on any other B series, you are better of using the ones that are made for it. The A20 manifold does not flow as great as the B series.
There are Cars with Dual Carbed DOHC engines. There was a B16 or a B18 or even a Darn B20 that was carbed. I have a picture, but there was speculation that it was not a B20 like i thought it was.
if my memory serves right. there were two F20 versions, The F20 found in the euro Type R accord (Older generatrions) and the F20C from the S2000. They were both Dual Overhead valve design and dont fit on the A20 block.
The F22s and F23s on the other hand were found in the USDM 4g and 5g accords, (6g too?). They wont bolt up either cause they were open decks.
The only head that someone tried to bolt up was a B21 prelude head and they said it was sticking outta the stock hood, and buncha stuff needs to be replaced which is not even worth it.
As far as trying to mate a Vtec head on a A20 block, hit up the search or go thru the FAQ, there were threads couple of years back concerning them. Please do not start another discussion regarding this cause it WONT WORK. people who have tried do no post here, so we, members who know of them, can attest to it and take it for our word. Its just not gonna work. We always try to balance two things, cost and benefit. Choosing wisely will let u know where side of the scale u will be tipping.
yeah i mentioned the open deck for the bore spacing issues. I think our bore spacing is like 90mm center to center of cylinder bores. i am sure the Open Deck motors have greater bore spacing to include the coolant passage.
The B21 lude head was put on a A20 block by one of the guys here, but the hood clearance was bad. Sean was talking about the A20 with a V-tec head, but it was never done.
davke: You need to go to the FAQ section and also the HOW-To section and read all the Sticky threads. Also go to the Performance section and read all the stickies. You seem to have a lot of questions but faint knowledge of what you are talking about. Read them, understand them and probably you will have a better understanding of things.
We need some pics of the A20 gasket on a B20A5 head. Even tho its hard to believe that such a thing is possible, I know aside from the hood Clearance problems, nothing else will be much of a hurdle. The other thing to worry about is the sensors as mentioned, but most probably we can try and use the stock sensors from the lude head and have it work. This is the second thread i am looking at the B20/B21 head mentioned. I wanna know if the Bore spacing is the same as the a20 (which is 90mm i believe). Someone start crackin up the pics man.
i think the hardest part of getting this motor to run is getting the valve timing set right along with the stock crank gear (which determines the TDC for every single piston) and in relation sets the valve timing of when to open and close.
i dont know if the B20A5 used a water pump that ran off the timing belt or not and if it did not, we might be able to use the B20A5 timing belt and the crank gear. I wish i had time to go to the junkyard and compare these things or better, work at a Honda dealership.