Quote Originally Posted by TDCRacing View Post
A 4'' intake with a length of 3 feet can flow well above 500 cfm's.



That is way above what an engine that has 500HP will use.


I did the 2 hours of math and searching to prove this.


You can't argue with cold air. It makes power. That's why intercoolers are so effective.You think cold air intakes are restrictive?? Think about how restrictive they are.


But i'm not here to argue so that's all i'm going to say.

It takes less than an inch of vacuum to create a very substantial rise in heat gain across the blower.

Yes, that length of pipe can support that amount of flow, but at what pressure differential are you quoting that flow number? If it's at more than an inch of vacuum, you need to take into account the adiabatic efficiency effects from the inlet vacuum, these effects are far from negligible. Also, you're quoting a length of straight pipe in your flow numbers. You do, however, need to concentrate on effective length, which takes into account losses for directional changes, i.e. bends. Most FWI's have at least one fairly extreme bend which adds a pretty substantial amount of effective length to the equation. How much effective length depends on the bend radius, the angle, the pipe diameter, etc.

You need to read what I said. Don't tell me cooler air makes more power, when clearly what I'm getting at here is that exact same fact. If the inlet temp difference is 10 degrees between two intake setups, which is roughly in line (if anything, it's on the high side) of what I've seen, and the difference in outlet temps is 50-60* (again, in line with what I've seen), then you're talking a difference of 40-50 degrees, favoring the open cone. I've verified this on my car, and seen similar performance differences on several other cars I've wrenched on and converted to open cones.

It might seem counterintuitive, but it's simply how it goes on these things.