I recently just started putting together a y block for my model a build. It just got rebuilt,and I have got it mostly finished. I have wondered about setting the carbs up. So I started asking around, WOW everyone has a different answer. I have heard I need to buy new carb bases without a idle circuit for the two outer carbs, I've heard I need a progressive linkage,I've heard all I need to do is remove and plug the powervalves on the outer carbs.I've heard block off the two outer carbs make them just dummy carbs. (not an option) why have three. Thats like having a noisy gear drive so people think you have a blower. I have rebuilt all three carbs to factory spec's, I had a progressive linkage from speeedway motors on my set up and is was really really sloppy and cheap, So I bought heims and dom tubing and made my own linkage which operates all three at the same time together. I just don't know where to go from here. Any option or advice would br greatly appreciated. I will attach picture of both speedway and my own linkage.Thanks
I've been running thre 94's on my 324" Olds since 1994 and have had little trouble. Try Race Cars in Retrospect for a good progressive linkage. 216 823 6167. PO Box 3116, Alliance. Ohio 44601. Remove the power valves out of the two end carbs and plug them. Next (on the two end carbs) you need to block off the fuel passage to the idle ports with small round pieces of gasket material that will replace the gaskets under the nozzle bars. Then turn the idle screws in all the way. Set all accel. pump links to "summer" setting. That's it. You may want to change the jetting in the carbs, but I never did. Good luck, Art
Thanks Art- I would like to go down that road instead of buying new base plates if I don't need to. Its about 380 for a kit at vintage speed, But it comes with linkage everything you would need. It looks like a really good kit.
Try http://www.y-blocksforever.com/forums/default.aspx they are pros on those engines and could probably help. BTW great color scheme. Looks familiar.
This should keep you entertained for awhile... http://www.jalopyjournal.com/forum/group.php?do=discuss&group=&discussionid=289
I bought the whole kit from Charlie at Vintage Speed for my Rochesters, great people to deal with and a fine product, just thought I'd mention it. I tried doing the modification to mine but the bases were shot and would not seal around the shafts and throttle plates. For $ 300.00 I was running like a dream.
Yeah Vintage speed is a shot in the dark. Could go well, could end up angry and frustrated. I get all my parts from dickster. I need to update the Holley page, I'll get on it..
Sounds like jamco...... Maybe I modify the carbs first then buy the kit if I don't have any luck. keep the info coming, I love to learn from people's experiences. I have a feeling in going to know a lot about running three duces soon, hopefully not the hard way..
I'm no expert, but do have a 6X2 setup with 94's. Keep your bases. Either hand fit or buy 11 degree throttle plates for the end carbs to get a better air seal. Close idle adjusters on end carbs - snug and not stupitd tight. Remove power valves from end carbs. Change power valve in middle carb to a lower setting because you'll loose the vac signal faster when you tip in the end carbs. Remove linkage and set base idle on center carb. If you get a bit of air bleed on the end carbs, you can crack the idle adjusters if you need to, but try to get it adjusted on just the center carb. Hook up linkage. Set accelerator pump linkage to give smallest squirt to start. After that, it's trail and error on the correct power valve in the middle and correct jets on the ends. Play with accelerator pumps as needed. I run mine on straight linkage - no progressive.
FWIW, V8 bob on here is running 3 97s on a flathead and they all work, all the time. The engine runs well and the mileage is not terrible; I think you might be able to try your 94s the same way. Maybe just remove the power valves on the end carbs and rely on the center carb to carry the engine during part throttle acceleration.
ive run a tri cab on my sbc for about 10 years now and all the idle circuits are working, nothing is blocked up and it works like a dream, my carbs were built by jere jobe and have been fantastic.
You may (or may not) enjoy this link: http://www.thecarburetorshop.com/Aftermarkettripowersetups.htm Jon.
Got the power valves out and the hole plugged and the idle screws closed off. Now I'm going to see if I can come up with a better linkage set up. Still riding the fence on progressive or straight up.
Still riding the fence on progressive or straight up. You did not say how big your Y block was, but depending where you read the 15/16" 94's flow 160-170 ish CFM. Also when trying to relate it to a modern setup, the standard for flowing two barrel carbs was 3" of vac and the four barrel standard is 1.5". So to do a side by side comparison you need to use about .71 of th etwo barrel flow. So use 3 X 165 = about 495 CFM in two barrel speak and about 351 CFM in four barrel speak. So running them straight up isn't overkill.
The engine size is a 283??Well it's a 272 .80 over so close to a 283. That will mess with the Chevy guys. I got the straight non progressive linkage and throttle return mocked up and ready to go black. Now I'm just working on a progressive piece that I can go back and fourth with.Internal spring instead of a external spring over shaft.