Can any one tell me the air intake CFM for this engine 3.5L.

 

i would honestly look at a picture of a stock one... then decide if you want more top end out of it or if you want more mid range then go from there .... could make the plenum bigger runners longer plunum bigger runners fatter ... or plenum bigger runners fatter and longer

 

Just building a air filter not a intake. and I found the formula thanks
You have to pick a max. rpm.
But if you wanted to spin it to 7200, for example:
3.5L = 214 ci
214 x 7200 x 1.0 (VE) / 3456 = 445.8 cfm at 100% VE
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