another question for fatride/others

[petepedlar]

Do we have to do anything with the power valve as far as adjustment in the center carb on a tripower? I'm following Fatride's past posts to the letter for the tripower carbs but I can't find anything on the power valve. Will the center carb work without the power valve being open all the time on a 409, mild street engine, 817's with the bowls cleaned up, 9.5 to 1, Ross pistons, 2 1/2" exhaust manifolds, roller rockers, cam not decided yet but nothing really wild..... looking for 330 - 350 HP out of it............

Dave

[fatride]

The power valve in the center carb should open only under high load low vacuum conditions. The problem is as we cam up the engine, vacuum at idle and cruise , low load, the vacuum is low enough that the power valve is open all the time or opens as soon as you crack the throttle. To set the power valve correctly you would need a vacuum pump and find the hole that pulls vacuum on the valve. The first thing I would do is find out what vacuum you are pulling at idle and cruise. If the engine produces anything over 16" of vacuum at idle the power valve should work ok. Below that and you would have to start cutting coils off the power valve spring. Just to be on the safe side of things I cutt a couple of coils off the power valve spring when I ran my three twos. The engine pulled 15/16" of vacuum at idle. You can buy the calibrated springs somewhere but I can't remember where I saw that info. :scratch

[petepedlar]

Thanks my friend !!!!

Dave