Gary_in_NJ wrote on 04/01/17 at 17:18:18:batman wrote on 03/31/17 at 19:05:05:
Tune your intake with a length of pvc and get the same boost with no time limit.and no moving parts.
How does a PVC intake runner make boost? There is zero science to support this claim. All you can do is minimize loss.
You have to know the science to make what batman says make sense.
It's a little bit like the exhaust... a long straight pipe with a burst of pressure traveling down it.
Once it gets going it develops momentum and in the case of the intake, only thing to stop is the piston.
Then the intake valve shuts and bounces the flow back the way it came.
Until the intake opens again, the flow snaps back to heads down the pipe again in one hell of a rush.
The trick is to make the intake long enough so the pressure wave doesn't get out before it turns around.
At high rpm, a velocity stack is all you need. mid-range on our thumper, you may need one a foot long.
the math is around here somewhere.