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This may be a dumb question but here goes. To make 700hp how much cfm should a carb flow to feed it. Holley says something like 780 but I have run tunnel rams with 1200cfm with 600 hp motors no problem. The reason I ask is because I am going to a single carb and a victor and don't want to waste time and $$$$$ trouble shooting. Thanks
 

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what is your displacement, what is your peak RPM? What is the intended use of the engine? ANd what manifold are you going to use to try and get this to work?
 

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Get the victor in a dominator flange, and get a tuned 1050, Ideal CFM for peak performance for displacement and RPM, 1100...
 

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Not to seem needy :shock: but what is the diff with the holley formula and yours? 1050 sounds great ,4500 flange no problem, and thank you :D !
 

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The Holley formula is presuming a peak RPM manifold vaccuum of 1.5"hg.

That isn't necessarily what is needed for a particular combination.
 

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Holly is based on min CFM required recomendation, or maintaining about 13" vacume at the booster or more.

A little more difficult to tune, but if you target .5 to 1.0 manifold vacume beneath the carb, your engine is going to be a whole lot happier (more HP)


Holly formula comes up with 916cfm recomended as min....
 

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I'm no expert on this, but my combo has an 1150 on a Stealth manifold, and I am at 550+/-hp with my 552. It had less than 2" of vac at WOT. I am not sure what difference there is between my dual plane Stealth and a single plane Victor though.
 
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