I'm running a Road Demon carb on my 305. It idles in gear at 16" of vacuum. I've seen a couple of different methods for selecting the correct power valve. It's got an 8.5 in it, right now. is this the one I need?
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Usually the choice is half of whatever your vacuum is at during idle in drive ( if auto equipped).
So close enough.
So close enough.
five7kid
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Yesterday
From http://www.holley.com/HiOctn/TechSer...o/TI-222A.html :
"A stock engine, or one that is only mildly built for street use, will have high manifold vacuum at idle speeds. To determine the correct power valve the vehicle should be driven at various steady speeds and vacuum readings taken. The power valve selected should have an opening point about 2" Hg below the lowest steady speed engine vacuum observed."
"A stock engine, or one that is only mildly built for street use, will have high manifold vacuum at idle speeds. To determine the correct power valve the vehicle should be driven at various steady speeds and vacuum readings taken. The power valve selected should have an opening point about 2" Hg below the lowest steady speed engine vacuum observed."