[jgreene6611]

I am in the process of putting tri power on a 350 chevy. i have 3 rochester 2GC small base carbs. The center carb has had no changes from its orginal runnig state other that a rebuild and the addition of a side mounted choke. The 2 end carbs have had the idle mixture screws plugged as well as the holes on top of the base. (belived to have whole idle circuit plugged). The rear vacumn ports on the base have been plugged as well as the venturi vacumn that it tradtionally used for the distrubter. They have been rebuilt as well with no chenges to the jets or acclerater pump. i have a new elebrock intake.
The center carb was put on the motor and driven on for a few miles to ensure there was no problems with it before it went on the tri power manifold. When i put the carbs on the new manifold the front and rear carbs were blocked off with gasket paper. the car strated and ran great. no problems. i only have fuel runing to the center carb. i pulled off the front carb and removed the gasket paper and put it back on. i started it up and it ran a little rougher than before but the car still idled. When i went to give it gas it was very hesitant and slow. then i removed the gasket paper from the rear carb and put it back on. when i started the car it ran really rough, barley even running.
then i taped up the top of the front annd rear carb to try to prevent vacum leak. when i closed the choke on the center carb the car runns a little better but still not great and it is still hesitant when i give it gas. i turned the idle screws out all the way on the center carb to give it more gas and that also smothed the car out some but not great.


What is wrong or were could the vacum leak come from? Are there more idle circuit holes that i need to plug? do i need those new thicker buterflies to seal the base of the carb better? does there need to be fuel run to the front and rear carbs? i have been as descriptive as i can if there is any more info you need to help please ask. i am lost and dont know how to stop the vacumn leak. If you would like to call collect or email me your phone number so i can call you that would be fine as well. 330 653-3563 usalley after 3PM ask for Jeff. alternate e mail is jgreene6611@yahoo.com

Thanks,
Jeff

[lanierledford]

Are the front an back carb. Idle screws backed all way off, if not its loosing vacuum through them.
I ran 3 x 2's way back when, it was a home made set up. I backed all way off the front and rear idles, set the mixture screws on these carbs. 1 1/2 turns out. set the middle carb. mixture screws with a vacuum gage to the highest reading I could get. ran a progressive linkage. lol

[jgreene6611]

The idle mixture screws are plugged with JB weld. They are no longer in use,

[MI2600]

Try this:

what Rochester carbs for tri-power

There's also a link in that thread for a Club Hotrod thread.

[jgreene6611]

Will centering those plates make that much of a differnece? it seems like its a pretty big vacumn leak.

[Henry Highrise]

Yes you need to get a fuel log and run fuel lines to all three carbs, Also you need to get the linkage kit for tri-power from www.speedwaymotors.com. It is a progressive linkage that is adjustable and allows you to run on the center carb until a certain speed or untill you kick the other two in...much like a 4 barrel. Your butterflys in your front and rear carbs must seal off perfectly...take your carbs off and with the butterflys closed shie a flashlight under them.....you should not be able to see any light coming from around them...they must be centered and the edges & roundness must be perfect. I had to work on mine quite awhile before I got them to seal off good.