I was wondering if it was possible to run a three duece intake only using one carb, the other two just mounted.
yes,as a matter of fact,i've been doing just that until i reach the 1000 mile mark breaking in my engine.you can do like i did and just have springs holding the outboard carbs closed ,or you can block the holes-george
What would you block the hole with? The reason I'm asking is, I have the intake , and one working carb. The other two carbs were given to me today. They are both stuck shut at the bottom.I guess you just wouldn't be able to run linkage to them?
ok ill let my secret out ,the two end ones are blocked one of the carbs butterfly were rusted through so i cut it out and just ran a shaft through, beadblast your bases and soak in diesel they might come loose, anyway it works good no tuning problems it just runs out of poop though it doesnt do burn -outs like i know it could
On a regular tri-power with a progressive linkage (the typical set-up), the center carb is the one that is running all of the time....the outer two just opens up whens you stomps alla the ways down on that there throttle! Block off the outer two by putting thin plates of steel between the carb bases and the intake....thirtytwo is right though...it's not gonna have enuf oomph to do burn-outs...you're just running one two barrel remember....take the butterflies outta the outer two and just get the shafts to turn...then you can put your plates under the carbs and hook linkage up to all of 'em and nobody'll be the wiser...that is, at least while you're parked....I guess i'm jsut bein' goofy, cuz i've always been one on the philosophy that "If it's on there, it works"....i can understand if you're trying to do something on a limeted budget though...multi carbs = lottsa $$$
Limited budget and it's a daily driver, and I'm not mechanically inclined enough to tune them all the time.
Yeah, the tuning gets to be an issue after a while, especially with a tri-power set-up....I'm gonna be runnin' six deuces on a 390 Caddy mill soon, but this a log style set-up, so basically you're dealing with two banks of carbs...you just gotta make sure that both sides are doin the same thing...kinda like non-progressive dual quads...sorta...
Get 2 gaskets, carb base to manifold, for each end carb. Cut up a beer can cut out 2 pieces of beer can same shape as carb base, cut your holes, put the beer can piece between the 2 gaskets & bolt the suckers down. After youhave removed the butterflies, figure out some way to block lines from fuel block to the end carbs, . Now you got a good 2bbl setup that looks like 3 deuces. Plus now you got an excuse to drink a beer.
probably the cheapest, most efficiant way to run just one two barrel would be to.. RUN A SINGLE TWO BARREL INTAKE!
if you can get the throttle plates loose i wouldnt remove the butterflys just make a progressive linkage so they dont have to open all the way and wont hit the block off plates, that way you will still have two useable carbs for when you get bored and want to make them all work!!!!
Try & get another 2 good carbs & run all 3, it a shame to waste a 3 duece manifold.I run all Primaries on my 3x2 & its not a problem. JimV
Eventually I am going to get two more carbs that work, but I am trying to get the body done before the Roundup.I just was wondering if it was possible to do this for a little while.
You really should hook them up to work eventually. YOU WILL NOT BELEIVE the acceleration difference. AND once you rebuild them and get them jetted right and the linkage adjusted right,you won't have to ever"tune" them. They'll just work.These carbs are probably the easiest to work on and any parts store will still have the simple,cheap rebuild kits for them. Oh yeah, and run K&N filter elements on those small chrome air cleaners. They outflow the paper elements by 150cfm.
94 & 97 end carbs can be blocked off with a beer can shim. Rochester carb butterflys hit the shim when they try to open. The dummy end carbs would need the butterflys removed or a slipping linkage system. I like to solder up the brass fitting at the fuel inlet so that no fuel gets into the dummy carbs. just added insurance against fuel leaks.
Run the center carb till you get another one rebuilt and working. Then block off the center one and use the outer 2 carbs together, NOT progressive. When you get the third carb running you run the center carb as your primary and the outer 2 carbs as secondaries with progressive linkage. The bullshit about synchronizing carbs is only needed if you run multiple carbs on a non-progressive setup. Don't let it scare you. It ain't rocket science.
Well, I got the two carbs freed up today, got all the living things out of them , tommorrow I will go get the rebuild kits. I know they are easy to rebuild, I did the one I run right now not too long ago.The ones I got yesterday are spotless inside minus bugs. So hopefully I can get these things working soon.
Alleycat, put the time into getting those other two working rather than blocking off etc. You'll never regret it once you see the difference. Once you have them properly set up there should be no reason to be "tuning / dickin" with them.
60's Style: Tell ya what, Bring your engine and your Uni-Syn. Since the end carbs are closed at idle on a progressive setup and don't even begin to open till 65% throttle or later I'll hold my foot to the floor while you use your Uni-Syn to synchronize the end carbs with the center carb and each other. Take your time. Afterall, I've got a lead foot and it's YOUR engine. I just get tired of bullshit experts scairing people away from using three carb progressive setups. The 2 outer carbs are just the secondaries for the center carb. It's not that hard to adjust the linkage so they both open together. I'll bet I hear at least a couple hundred so called experts a year say how they tried progressive linkage in the old days but they couldn't get it to idle because of the progressive linkage and they hated using the Uni-Syn. Then when you ask, they're more than happy to explain how to use it get the carbs synced so it'll idle. Like I said, bullshit! Right up there with the boogie man and bigfoot. If it won't idle, you've got leaky carbs or problems with the center carb. It ain't rocket science and it ain't mysterious voodoo.
this is from a guy with a gold plated chassis if you are using the correct outer carbs you will have a hell of a time running without a primary. Paul
Anyone have any pics of their progressive linkage? What I'm hearing is the linkage on the center carb stays the same , and the progressive linkage hooks to the other side of the carbs. Is this right?
i got a tri-power with progressive linkage hooked up, but im a retard when it comes to how it works.. so smokin joe, with the progressive linkage, you need to sync the 2 outer carbs together, then tune all 3, and thats it?
Since i'm headed there too, on the rochester end carbs do you HAVE to use the thicker butterflies and block the idle circuits?, or can you make them run decent with stock 2 barrels?
I just ran a picture of the linkage i made for mine( progressive)If you want i'll post it again. Liek i said before, miones all primaries & I adjust all 6 idle screws with no problems,i set each one like its the only one.
Here's how the process works. You have 8 cylinders, 4 in each bank. Above that you have what's usually called a log type manifold. It's either a big chamber that feeds all eight cylinders or sometimes it's 2 chambers, 1 feeding the left bank and the other feeding the right bank. Some flathead manifolds are this way. Manifolds are made both ways. Now we get to the fun part. At up to 65% or more throttle, you have 1 carb feeding into the log to all 8 cylinders or with the split manifold the left venturi feeds the left bank and the right venturi feeds the right bank. You use the center carb for this as you want the fuel/air mixture to feed all cylinders in the shortest possible distance. Your throttle pedal connects directly to this center carb. Until the throttle opens to the point where you want to use the outer carbs they are closed and if they don't leak air thru the butterflys, under the baseplates, or dribble in gas, the engine doesn't know they exist. You are running on 1 2 barrel. That's it. Can't be more simple than that. You put a choke on the center carb for cold weather. You can run around all week and never open the outer carbs unless you have a heavy foot. The rest of the progressive is designed to turn the outer carbs into secondaries just like on a 4 barrel. The 2 outer carbs have a rod connecting them together so they both work as one. The center carb has a rod and adjustable slider that moves back and forth but doesn't cause the secondaries to start to open until a stop on the rod is contacted. Once the stop is contacted the linkage will move the secondary carbs to open together, and the linkage is usually leveraged or cammed so that when the center carb reaches wide open throttle, the outer carbs are also wide open. Now from the time the outer carbs start opening, you not only have fuel/air mixture entering the log manifold from the center, but from nearer the ends of the log as well. The front carb will primarily feed the front part of the engine and the rear carb will primarily feed the back part with the center still running the middle. This is of course still one big log feeding all 8 cylinders or 2 logs feeding 4 cylinders each depending on the manifold design. All you have to do is make sure the linkage on the outer carbs opens both carbs the same and that they are both giving the same air/fuel shot to the log below them. This is finaly where you synchronize the carbs together on a 3 deuces progressive setup. Unless you're using that lead foot, you're running a 2 barrel so don't let syncronizing the carbs scaire you. It's more of a tuneup for the race thing than an "Oh My Gwad, I'll never get it to run!" type thing. Hope I explained that well enough. Had to hurry it as I'm getting off work.
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