I need a little help just put on a tripower end carbs are sealing good i just cant get the idle down its a basic 350 crate motor center jet is 58 outers are 55. i'ver had these off and on more times.... please chime in and help i know there is an answer out there
You didn't specify what carburetors are being used; but the center SHOULD be large enough to run the engine. If the above is true, and the ends are blocked; then a good possibility is a vacuum leak; ***uming the engine was running well prior to the installation of the tripower. Jon.
Yes it could be a vac leak, but I would pull the center back off; then shine a light up through, to see if the throttle plates are completely shut with the idle speed screw backed off. Maybe even look down the bores first, before removing it, in case the plates are hanging up due to whatever reason.
If you are running 2GC carbs look for a vac leak where the old choke linkage bolted to the main body itself. There is a 1/4 inch or so hole that is sometimes drilled to the vac chamber and sometimes not. Check all 3!!! If you are having a hard time finding it just let me know I will post a pic for you.
I was also just thinking that if somebody put the longer aftermarket throttle shaft in the center carb, they may have the throttle plates crooked after swapping the shaft. If the two plates are not dead nuts centered, then the plates will hang open a little.
Throttle plates are cheap . Make sure they aren't bent or make sure they haven't been sanded off center . Still I would check all the vacuum lines first and make sure the linkage isn't hanging up . Unhook the linkage then look down the carb with a light . If the throttle shafts are new , maybe they aren't tight and need to be drilled with new bushings .
This is the method I use on my small and big block Ford tri-power. Lightly seat the idel screws on the front and rear carbs. Back of the fast idel screws and close the ****er flies as far as they will go on the front and rear carbs. Reseat the idel screws so they just touch the ****er fly levers. Mine are closed down to where they somtimes stick in the bores when the engine is cold. Do all of your idel tuning off of the center carb as if you were running a single two barrel. You will still have the advantage the high speed circuits on all the carbs when you step on it. It stays tuned and runs trouble free. I did this out of ignorance and is not the factory method but it works great.
Sounds like va***e leak.........I had a similar problem with 3x2 Rochesters where the acelerator rods were holding the ****erflys open just slighty. I ended up bending them( shorten them) so they allow the ****erflys to shut completely.
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