Originally Posted by BillBoost37
Why would 3.5 with freeer flow than 3.0 not be optimal?
3.5 will not create as much velocity.
How much an engine is flowing (not how much it can on a bench) is directly related to hp. There is no reason a 150-200 whp car needs a 3.5" intake.
Look at max effort setups with similar power levels and see what size intake they make the most power with. 3".
The more you can charge the plenum with adequate flow, the better. Too big a cross-sectional area, keeping the same flow, will slow velocity due to turbulance. The flow cannot become developed.