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lostforawhile
11-03-2006, 04:20 PM
does anybody know if the dual carb 88 lude manifold bolts up to our block? I don't believe it's cvcc due to the fact the intake and exaust are cross flow. I don't care about the crappy keihin carbs,thats an even worse bowl of troubled spaghetti then what I have now. I was thinking of setting up a couple of honda bike carbs as duals on that manifold. remember I have the use of a machine shop and access to aircraft grade aluminum. that makes making adaptors,linkages etc. relativily straight forward. any input on this would be appreciated. or if anyone else has done bike carb conversions before. not even sure what particular carbs to look for yet as this is in the idea stage. this idiotic keikin POS is about to drive me nuts. If I didn't have to drive this car everyday,I know where there is a pair of SU carbs on an old MG,I enjoy tinkering with those type of carbs and still remember how to rebuild them with my eyes closed,but they are some of the most unreliable carbs ever made. if I was driving this car for fun it wouldn't bother me to have to stop on the side of the road and tear into a carb,but not on a daily basis. on this same subject does anybody remember if the old alfa's had webbers stock? there is one here in the yard also and it would be sweet to open the hood and see dual sidedraft webbers. they are closed until monday though

A20A1
11-03-2006, 05:21 PM
the head + manifold will.

well hrm... the SOHC lude, not the DOHC.

lostforawhile
11-03-2006, 05:36 PM
so what is the issue with the manifold fitting on our head? is it the bolt pattern or what? I think this is the single overhead cam. I'm going to consult my chiltons honda manual also. so you are saying the single overhead cam one can be swapped out? if it will work will be a good time to get some cyl head work done

Vanilla Sky
11-03-2006, 08:35 PM
mounts differently. go DCOE. i'm sure you can get a manifold made since you have a machine shop available.

rustlude87
11-03-2006, 09:03 PM
the 88 has a b20a3 which won't fit on the A20a3, your better off doing webers

lostforawhile
11-04-2006, 09:54 AM
didn't some of the preludes have the a20 with the dual keihin sidedrafts? this is def not a dual overhead cam motor the valve cover is way too small. I've got a pic somewhere let me see if i can find it. I wondr if it's a late 87 model.

lostforawhile
11-04-2006, 10:22 AM
here are a couple of pictures of it,maby someone can identify exactly what I've got. i hope this manifold might fit,it would give me the option to do something completly different. http://www.imagestation.com/picture/sraid218/p093048a9234e8939401b8a6a53d2022b/ec335f5c.jpg
http://www.imagestation.com/picture/sraid218/pc7c728453fdc7b8998c46beb21063cb4/ec335f6a.jpg

snoopyloopy
11-04-2006, 10:29 AM
b20a3 was sohc. that's the b20a3.

stat1K
11-04-2006, 10:30 AM
definitely looks like an a20 just with a different valve cover. which isn't that strange. but it definitely looks like an a20 but the car doesn't appear to be the right year, it looks like an 88-91 at least the bumper and the headlight buckets do. but i don't think the lude came with any other variant of engine other than the b20 a20 and b18 but the b18 was still dohc if i'm not mistaken. definitely a strange one! try it though!

edit:
after snoopys comment i looked it up and sure enough.
huh! i've never seen a sohc b20 that's so weird looks just like an a20 minus the valve cover... it definitely is tilted back like all b series... so weird.

Vanilla Sky
11-04-2006, 11:34 AM
like i said, don't bother. you'd have to correct the angle on that manifold so the carb operates correctly. by the time you've done that and machined the manifold to fit, you've built your inlet manifold. toss a set of DCOEs on there and be happy with your newly gained 25 HP (most likely a gross overestimate).

2ndGenGuy
11-04-2006, 02:31 PM
That's probably not an A20. It leans backwards. The A20 leans forwards 15 degrees.

shepherd79
11-06-2006, 08:02 AM
even if you find A18 dual carb engine from 86-87 prelude, you still have to swap the head with intake manifold. the reason, a18 and a20 heads have diff intake manifold bolt pattern. By going with A18 head you can increase your compression a little too.

lostforawhile
11-06-2006, 01:48 PM
even if you find A18 dual carb engine from 86-87 prelude, you still have to swap the head with intake manifold. the reason, a18 and a20 heads have diff intake manifold bolt pattern. By going with A18 head you can increase your compression a little too.
so it will just bolt up? no major engine mods needed? I'm going to start working on another engine soon anyway so I could just get this head rebuilt. then I would be able to fit up the dual carbs on the head off of the car. all I would need to do is figure out the angle the head sits on the a20 then build a stand for the head to make sure the carbs are level. what about the exaust manifold? is the bolt pattern the same? or do I need to get the manifold also? also with the prelude head are there more options for headers? it's actually a pretty good idea. I think fitting a set of honda bike carbs would work pretty well. I may have a little bit of a problem off of choke but they are really easy to work on and more options for tuning. I just have to figure out what cc bike and divide by half for two carbs.

shepherd79
11-06-2006, 02:22 PM
boy you have a lot of researching to do.
where should i start.
well, 86-87 prelude has two keihin carbs. They are like bike carbs but only two. the stock ones are very small. i hope you upgrade them with something better.
the cylinder head from A18 will bolt up to A20 block without any problems. You may want to check on the size of the valves and the size of the ports. the reason i am saying that is because they may be a little smaller than A20 head, but i could be wrong.
You can use regular A20 manifold. It will bolt up without any problems. they are no other options for headers since A18 and A20 share the same header bolt pattern.
If you are going to upgrade the carbs go with 45mm at least. get the biggest you can find. Remember, they are going to be working twice as hard as if you had 4 bike carbs.

PS. there are pictures of people running 4 bike carbs on A20 montors without any problems. you will make intake manifold the same way as if you had 4 individual throttle bodies.

lostforawhile
11-06-2006, 05:59 PM
boy you have a lot of researching to do.
where should i start.
well, 86-87 prelude has two keihin carbs. They are like bike carbs but only two. the stock ones are very small. i hope you upgrade them with something better.
the cylinder head from A18 will bolt up to A20 block without any problems. You may want to check on the size of the valves and the size of the ports. the reason i am saying that is because they may be a little smaller than A20 head, but i could be wrong.
You can use regular A20 manifold. It will bolt up without any problems. they are no other options for headers since A18 and A20 share the same header bolt pattern.
If you are going to upgrade the carbs go with 45mm at least. get the biggest you can find. Remember, they are going to be working twice as hard as if you had 4 bike carbs.
PS. there are pictures of people running 4 bike carbs on A20 montors without any problems. you will make intake manifold the same way as if you had 4 individual throttle bodies.yea the stock keihin carbs and nightmare control system are going in the trash,I just want the cyl head and intake manifolds,with the dual intake manifolds I have the option to run the dual sidedrafts. I work in a machine shop so I can make any modifications to the manifolds I need to or make any adaptors needed. there is no way in the world I would even attempt to hook up that factory dual carb system and controls again,thats the factory carb spaghetti mess X 2. any suggestions on particular sidedrafts that would work well with this system? they have that Alfa romaeo out there in the yard,it would be nice to find it has dual webbers on it. good place to start. I haven't had the chance to look at it yet. it's an older convertible,possibly from the seventies,they came factory with that crazy mechanical fuel injection system,but it was so much trouble that a lot of them were converted to dual sidedraft webbers. there are also a couple of MGs out there, it was popular to convert them from dual side draft Sus to webber. lets hope they were

shepherd79
11-06-2006, 07:34 PM
since you work at mashine shop, why don't you keep A20 head and make intake manifold to run DCOE carbs.
run two 40 or 45 mm sidedrafters and you will be a lot better off than some bike carbs.

lostforawhile
11-06-2006, 08:17 PM
well I could do that,but if the a18 head is good,being on a lude of that generation I would assume the valves are probably the same,why not get that head rebuilt and use the existing manifolds? I need to get a head rebuilt anyway since i'm going to be building another motor. it's only 150 bucks if I have the core. parkers machine shop here has been rebuilding motors for 50 years and do excellent work. I'm not rushing this project,i'm going to be building this motor over a period of time. thats why it's in r&d I will keep updating this project as it progresses. I really hope one of those brittish cars has a set of webbers already on it. It doesn't bother me to rebuild them,i have a good source for parts already. I also have a friend with an mg thats been under a collapsed barn for years and years. he said it might have had dual webber sidedrafts on it.

Vanilla Sky
11-06-2006, 08:23 PM
tim, here's a tip. if you even hear the word "weber" and "sidedraught" in the same sentence, go right then and grab them. DCOE series carbs are worth about $50 for the body only on ebay.

lostforawhile
11-06-2006, 08:37 PM
best place i know of is pierce manifolds,they have everything webber available.
motivation:
http://www.piercemanifolds.com/carb14.jpg
darn,just drooled on my keyboard

Vanilla Sky
11-06-2006, 08:42 PM
tim, sign onto AIM.

lostforawhile
11-07-2006, 03:08 PM
tim, sign onto AIM.I can't everytime I sign on to aim my computer crashes,I will pm you if you want to give me a hollar on the phone,I talked to the tech guy at pierce manifolds today,he said they have another carb that is very popular,it's the OER brand,these are sidedrafts just like the webber,they even use webber jets etc. but they are japanese sidedrafts.so you can put a set on a lot cheaper then the webbers and use webber parts to tune them. they will even set up a set in tune however you specify when you order. http://www.piercemanifolds.com/Images/Catalog/P13-006%20OER.JPG

lostforawhile
11-07-2006, 04:28 PM
well the car with the manifolds is an 88,it is a single overhead cam though. I looked it up on the majestic honda site and it's def an 88. wierd. so will the dual carb manifold fit the a20 head or will the lude head fit the a20 block? this changes everything

shepherd79
11-07-2006, 07:42 PM
that year head will not fit accord block. i just said that a few post up..
You need 86 or 87 year prelude.

cygnus x-1
11-07-2006, 09:22 PM
This might help. Here are some pics of my A18 (1.8L) carbs, intake, and head from an 87 Prelude:

http://bluegreenlabs.com/Prelude/A18/A18Carbs.jpg
http://bluegreenlabs.com/Prelude/A18/A18CarbsBottom.jpg
http://bluegreenlabs.com/Prelude/A18/A18Intake-Carbs.jpg
http://bluegreenlabs.com/Prelude/A18/A18Intake-Ports.jpg
http://bluegreenlabs.com/Prelude/A18/A18Head.jpg

Now while you might be able to modify this intake for Webers I think it would be faster and easier to build one from scratch. Webers have 2 barrels per carb and the stock carbs (and intake) only have one, so it will take a serious amount of hacking to get them to fit up. The stock intake also has water passages that will probably get in the way.

The A18 head has an advantage of smaller ports for more velocity but the ports are not centered to the combustion chambers. So one valve tends to flow better han the other, and in fact on mine the far valve has a lot more crud buildup than the closer valve. The valves are the same size as an A20 head. This head will fit an A20 block and so will an A20 head fit an A18 block. (I just had my A18 block bored to the stock A20 size and bolted an A20 head to it, so I know it fits.)

C|

Civic Accord Honda
11-08-2006, 12:12 AM
whay not do a EFI SAwp wouldent efi = more powe then a carb ?

MessyHonda
11-08-2006, 07:21 AM
whay not do a EFI SAwp wouldent efi = more powe then a carb ?


a weber carb conversion is easyer than taring apart the car just to put a silly EFI swap plus its only like 20 extra hp....the weber you can get rid of your old carnd and just bolt in on and tune it...and you should have at least the same power

shepherd79
11-08-2006, 07:44 AM
actually properly tuned DCOE carbs with headers, full exaust and mild cam can make more power than EFI with the same mods.

Civic Accord Honda
11-08-2006, 01:46 PM
so sometims carbs are beter
i like crabs beter thay are easyer to work on

lostforawhile
11-08-2006, 02:16 PM
plus a nice set of sidedraft carbs is just so much nicer to look at then a fuel injection system. I guess I'm just old school. :) I think the tuning possibilities on this car would be a lot greater with good carbs then trying to modify the factory fuel injection system. the other possibility I'm looking at is a possible set of sidedraft SU carbs off of an mgb. these were almost as famous as webber carbs and they have many parts available for tuning. there were many roadraces and rallys won running SU carbs. they would need to be rebuilt of course,but it's one of those enjoyable projects you work on a bit at a time. from what I can see looking at this picture, http://bluegreenlabs.com/Prelude/A18/A18Intake-Carbs.jpg it looks like I could just mill the factory inlet flanges off and tig the webber flanges on or the flanges I would have to make for the SU carbs. if I run into a water passage problem I'll tig it off and not run a heated manifold. I already installed an extra temp sensor in the thermostat housing anyway. it's pretty easy to make aluminum pieces to get rid of the egr valve etc. the other thing i might run are OER carbs,these are basically japanese webbers,they use all internal webber parts and are tuned exactly the same. the only real difference is price talking 600 bucks for a set vs 1000. the tech guy at Pierce said they would even tune them the way i wanted.

lostforawhile
11-09-2006, 06:49 PM
I have an extra carb intake in my junk,so what I'm thinking of doing is where the two runners on each side meet up into one,I may cut it straight across then mill it square and tig the webber mounting plates on to the runners. one barrel for each runner. that way I can cut off the excess aluminum around the egr valve etc. and grind it all smooth and make it look nice. what I need to do first is put the manifold in the bridgport and make a block that fits under one side of the flange while the intake flange for the carb is straight up and down vertical and lined up with the quill. this way after all that mess is cut off, the block will act as a reference for milling the intake nice and square and the carbs will be level with the manifold bolted to the head. after I get the carb mount flanges from pierce,I may have to mill more of the intake off,all I will have to do is put that block back under the intake flange mounted in the mill,and the manifold will be at the right angle.

cygnus x-1
11-09-2006, 08:38 PM
Ok, yeah. You mean an extra A20 intake right? I was thinking the same thing. Cut it just before the 4 runners combine into 2. That sounds a lot more feasible, and accord intakes are everywhere so you can afford to trash the first try if it doesn't work.

Vanilla Sky
11-10-2006, 06:37 AM
you'd have to reshape the runners if you were going DCOE. the carbs are round and the ports on the head are oval. it's nothing some machining couldn't fix, but it's certainly something to think about. i'd personally not use much more than the flange from the stock IM.

lostforawhile
11-10-2006, 03:03 PM
you'd have to reshape the runners if you were going DCOE. the carbs are round and the ports on the head are oval. it's nothing some machining couldn't fix, but it's certainly something to think about. i'd personally not use much more than the flange from the stock IM.thats exactly what I did.hehe took a band saw to it. I'm going to keep some of the runners but not much. If I measured right the angle difference between the flange and the original carb mounting pad is 15 degree. in other words if I machine off the edges of the runners at 15 degrees and weld the flanges from pierce to them the carbs will sit level when the flange is mounted to the head. other question for those who are running dual sidedrafts,where did you mount your vaccume point for your booster? and where did you pull vaccume for the pcv valve? it's important to keep the pcv valve as it helps keep sludge out of the engine. also does anyone know the thread for the vaccume sensor on the back of the manifold? thats actually not for emissions,it retards your timing when the engine is cold to help start eaisier. it's pretty easy to set that back up. I thought instead of the heated manifold I would run an aluminum block on the firewall to hook the bypass hoses together. that way i can hook up that vaccume piece and the temp sensor and they will still function normally.

2oodoor
11-10-2006, 03:25 PM
boy you have a lot of researching to do.
where should i start.
well, 86-87 prelude has two keihin carbs. They are like bike carbs but only two. the stock ones are very small. i hope you upgrade them with something better.
the cylinder head from A18 will bolt up to A20 block without any problems. You may want to check on the size of the valves and the size of the ports. the reason i am saying that is because they may be a little smaller than A20 head, but i could be wrong.
You can use regular A20 manifold. It will bolt up without any problems. they are no other options for headers since A18 and A20 share the same header bolt pattern.
If you are going to upgrade the carbs go with 45mm at least. get the biggest you can find. Remember, they are going to be working twice as hard as if you had 4 bike carbs.
PS. there are pictures of people running 4 bike carbs on A20 montors without any problems. you will make intake manifold the same way as if you had 4 individual throttle bodies.
very well farmed info Shep, say Lost, Ive seen that motor before in a prelude se-i. at the jy. Tim really got the attention of the real motorheads here, R&D threads are a good place to browse about. Do you have access to C&C machine ??? computerized setup? you can draw out and design your own manifold or adaptor blocks to make anything fit. Depends on how much access to jy parts your have and are you willing to cross the Honda line and get fuel delivery system from another make ????carbed of course. Bike jy are hard and few and far between keep that in mind when your planning, ever break a jet or something when serviceing carbs your screwed. I say use a weber set up, can you find some vw bug dune buggy parts.. lol Intrigued RooDooToo

Vanilla Sky
11-10-2006, 05:07 PM
my favorite way to pull vacumm is to tap all of the runners and build a vacuum manifold for everything to run off of.

lostforawhile
11-10-2006, 06:52 PM
very well farmed info Shep, say Lost, Ive seen that motor before in a prelude se-i. at the jy. Tim really got the attention of the real motorheads here, R&D threads are a good place to browse about. Do you have access to C&C machine ??? computerized setup? you can draw out and design your own manifold or adaptor blocks to make anything fit. Depends on how much access to jy parts your have and are you willing to cross the Honda line and get fuel delivery system from another make ????carbed of course. Bike jy are hard and few and far between keep that in mind when your planning, ever break a jet or something when serviceing carbs your screwed. I say use a weber set up, can you find some vw bug dune buggy parts.. lol Intrigued RooDooToo
well I'm going to modify a factory manifold and get the plates for making the manifold from pierce. I'll probably get the oer carbs from them too,they are the same thing as webber 45s but are japanese and use webber parts so tuning is easy. about half the price for a set also. 500 vs 1000. don't have a cnc machine available so it's done the old fashioned way. most of what you need for making the sidedraft manifold already exists by simply cutting them off and machineing them at the junction where the tubes come together. piece sells the plates that match the webber carb base the OER uses the same pattern. you simply tig them on to your manifold. and blend in the plates.

lostforawhile
11-11-2006, 07:16 PM
ok who has done dual carbs on here before and what problems have you run into while doing the setup? I like the idea of doing the vaccume manifold,I'm going to make the aluminum block that mounts to the firewall for the bypass hose and temp sensor vaccume control for the dis. if I could find some small liquid filled vaccume gauges,I thought of running one on top of each port, not just for looks,but for help in tuning the carbs. I'm going to kep my air cleaner assembly due to the time and trouble to make it. I will build a manifold that fits across both sidedrafts and duct air from my air cleaner. all I need to do is find another couple of bracing points to mount the back of it to on the block.

lostforawhile
11-13-2006, 05:06 PM
well it looks like I'm going to go with the 2 single barrel SU carbs,I found a ton of info on the internet and I never realized how many different kinds of cars people have installed them on,brittish,german,and japanese alike. I also never realized they were made until 88. I remember working on them as a kid and they are fantastic carbs,and so simple. yet they have survived all these years due to the fact they work so well. heres a little bit of info and a funny article as well on them. http://sw-em.com/su_carbs.htm

A20A1
11-13-2006, 06:44 PM
Holy sausages butchman!

"Sausage Skinners Union"

:lol:



wow, beautiful exhaust display...
reminds me of the bike in the "AKIRA" movie :)

http://i23.photobucket.com/albums/b351/Wendy_girl/su_carbs_v24bike.jpg

shepherd79
11-13-2006, 07:23 PM
well it looks like I'm going to go with the 2 single barrel SU carbs,I found a ton of info on the internet and I never realized how many different kinds of cars people have installed them on,brittish,german,and japanese alike. I also never realized they were made until 88. I remember working on them as a kid and they are fantastic carbs,and so simple. yet they have survived all these years due to the fact they work so well. heres a little bit of info and a funny article as well on them. http://sw-em.com/su_carbs.htm
there is a car at the junk yard that has simular carbs. it is MG with very small engine, but the carbs look just like it.

lostforawhile
11-13-2006, 07:48 PM
there is a car at the junk yard that has simular carbs. it is MG with very small engine, but the carbs look just like it.they came in different sizes,if you get a chance see how much he wants for them and the linkages of course. also if you see any numbers on them let me know. the sizes are the sizes of the throttle bore,like 1 1/4 1 1/2 etc. I would need two of them at least 1 3/4 size bore or larger. it was common to put the bigger su's on smaller displacmment blocks for racing.

reliantkcar
11-14-2006, 12:25 PM
what about opening up the carb A20 manifold and putting a edlebrock 650 on there..................

lostforawhile
11-14-2006, 02:52 PM
what about opening up the carb A20 manifold and putting a edlebrock 650 on there..................
no comment

shepherd79
11-14-2006, 04:10 PM
650 cfm would be too big of a carb.
I had 350 holley 2 barrel carb on my old accord and it ran rich on low rpm but high rpm it was great. it was pulling like crazy on high rpm.
I still have carbed manifold that i ported for holley. all you have to do is drill and tap new wholes for the bolts that hold the adapter. i think i even have adapter somewhere too.
it is easy to do since it is aluminum.

A20A1
11-15-2006, 02:16 AM
what about opening up the carb A20 manifold and putting a edlebrock 650 on there..................
650/919 CFM , no ways :)

a 390, maybe 450, or 480 4bbl but you should divide the manifold to help the low end.

http://www.3geez.com/forum/showthread.php?t=37554&page=2


Thing is even with the larger carb there are points in the stock manifold you can't open up, so you'll be limited not by the carb but by the restriction in the manifold. Eventually if you want to make more power you will have to go the custom manifold route.

http://www.3geez.com/forum/attachment.php?attachmentid=3879

reliantkcar
11-15-2006, 11:02 AM
Only reason I asked is because my friends dad has a 48 dodge with a chevy 350 in it if I put a new carb into it I get the old one. So I was just throwing an idea out there . BTW the biggest engine I currently own is a B20A5.............

A20A1
11-15-2006, 10:09 PM
Maybe you could make the 650 a 3bbl.


Close up one of the primary throttle ports might give you low rpm back.

The next big challenge will be working on when the secondaries will open.

Is it a vacuum secondary?

How large are the chokes? Primary/Secondary

How large are the throttle plates? Primary/Secondary.


This is the AVS series... this one allows you to adjust when the secondaries kick in... :)
The manifold would have to have a 3bbl plate inbetween the carb and plenum to help keep primary fuel delivery a little more equal to both sides of the manifold.

http://i23.photobucket.com/albums/b351/Wendy_girl/car%20stuffs/3bbl_con4bbl.jpg

A20A1
11-16-2006, 01:31 PM
This guy is funny.
http://www.moparchat.com/forums/showthread.php?t=56571



Hey shep, was your carb progressive or synchronous.

2oodoor
11-16-2006, 02:42 PM
ok who has done dual carbs on here before and what problems have you run into while doing the setup? I like the idea of doing the vaccume manifold,I'm going to make the aluminum block that mounts to the firewall for the bypass hose and temp sensor vaccume control for the dis. if I could find some small liquid filled vaccume gauges,I thought of running one on top of each port, not just for looks,but for help in tuning the carbs. I'm going to kep my air cleaner assembly due to the time and trouble to make it. I will build a manifold that fits across both sidedrafts and duct air from my air cleaner. all I need to do is find another couple of bracing points to mount the back of it to on the block.
boy am I loving this thread, and I am totally intrigued Tim by your creative think tank plus 'counterforming' foresight ability, also I will mention Im glad A20A1 chimed in there are so many motorhead unstoppable engineers in this threadm Vanilla Sky, Shep, all of yaas. Thanks for the links too, I was not aware of the 'japan webers' , and A20A1 that bike is you bro, raging bull, never saw a three barrel carb quite like that one either.
OK regarding the dual carb setups, my 2 cents worth from working on corvairs and vw's is yes you need a set of very good vacuum guages Small aircraft tool specialty vendors is a good place to look. A lot of what your working with here is old school, remarkable shitzit Lost... The carbs, when you build them, ensure they are identacle as possible regarding specs and settings you can not get to once installed, attention to detail will really come into play. Porting &polish of the intake mani. under them will need to be presice as possible too I figure. I use to have a trio setup of vacuum guages to sych carbs with. Just like you expect with weber style carbs, you are constantly trying find the best of both worlds to get it tuned, thus having mulitlples haveing them be perfect matched sets really helps. LIving in Ga. will be a little headache since we get several months of extreme temp changes throughout one day, that trend is moving further south so know you have seen some 40+ degrees changes inside one 24 hour period.
your really motivated dude, this is awesome R & D , and what year is the mg under the fallen barn? restorable mg and mg minis are hot right now, I would not mind running across some deal on one, esp a mini mg.

shepherd79
11-16-2006, 03:56 PM
This guy is funny.
http://www.moparchat.com/forums/showthread.php?t=56571



Hey shep, was your carb progressive or synchronous.
my carb was synchronous. it was motorcraft 350 or 375 cfm (not sure what exactly it was). i was told it was 350cfm. like this one. http://www.carburetorfactory.com/expvw07.html

If you are not sure which carb you want to run look here (http://www.carburetorfactory.com/evindex.html) and find the one you like. i had my hands on Rochester 2gv. It was nice a small carb. it was smaller than motorcraft one but just a little bigger than stock keihin.
Probably close to weber. i was going to use it, but that is when my car got some rear damage.

A20A1
11-16-2006, 05:44 PM
thats great... at least I can see the 3bbl working now. :)

lostforawhile
11-16-2006, 08:25 PM
boy am I loving this thread, and I am totally intrigued Tim by your creative think tank plus 'counterforming' foresight ability, also I will mention Im glad A20A1 chimed in there are so many motorhead unstoppable engineers in this threadm Vanilla Sky, Shep, all of yaas. Thanks for the links too, I was not aware of the 'japan webers' , and A20A1 that bike is you bro, raging bull, never saw a three barrel carb quite like that one either.
OK regarding the dual carb setups, my 2 cents worth from working on corvairs and vw's is yes you need a set of very good vacuum guages Small aircraft tool specialty vendors is a good place to look. A lot of what your working with here is old school, remarkable shitzit Lost... The carbs, when you build them, ensure they are identacle as possible regarding specs and settings you can not get to once installed, attention to detail will really come into play. Porting &polish of the intake mani. under them will need to be presice as possible too I figure. I use to have a trio setup of vacuum guages to sych carbs with. Just like you expect with weber style carbs, you are constantly trying find the best of both worlds to get it tuned, thus having mulitlples haveing them be perfect matched sets really helps. LIving in Ga. will be a little headache since we get several months of extreme temp changes throughout one day, that trend is moving further south so know you have seen some 40+ degrees changes inside one 24 hour period.
your really motivated dude, this is awesome R & D , and what year is the mg under the fallen barn? restorable mg and mg minis are hot right now, I would not mind running across some deal on one, esp a mini mg.the mg has been sitting under a colapased barn with no top for years,I'm sure it's destroyed. SU carbs are very easy to bring back from the dead. even if frozen in place. I'm trying to find one of the later sets from 87-88 yes they made them that long,I found an SU tuning book from a rare book search site,need to get that ordered. only one they had. the famous one like on the site. I think I'm going to send the carbs off to import carbs.com he said he can rebuild them,and get them pretty close. there is a wealth of info and parts available on the web about these carbs. these are the original import tuner carbs. it seems to be becoming popular with the datsun 510 guys now to use them on their cars also.

lostforawhile
11-20-2006, 03:38 PM
a thing of beauty BWAHAHAHAHAHA!!
from a datsun 510 sss
http://i16.ebayimg.com/03/i/000/78/59/50a7_1.JPG
http://i15.ebayimg.com/04/i/000/78/59/50de_1.JPG

A20A1
11-20-2006, 05:25 PM
awesome. :)



It even has a balancing tube to get a more stable vacuum signal from behind the two carbs.

So you going to weld that to the stock manifold?