more length = more resistance
The OEM intake was designed STRICTLY for Normally Aspirated cars.
The Helmholtz theory only takes into account atmospheric
pressure to get up to 130% Volumetric Efficiency at a tuned
RPM.I've found substantial scientific documentation that supports this. The ideal intake for a turbo car has a short runner that
maintains a SMOOTH flow (the shorter it is, the harder this
is to maintain) with out much resistance. The second most important factor is SLOWING the air down
before the runners. This is why most performance intake
manifolds have a large surge tank. The surge tank (or
plenum) serves two major rolls. It absorbs and cancels
intake valve pulsations. The more you quench this wave
action, the more air you can get into the cylinder. The
second is to slow the air down. The slower the air at the
plenum, the more controlled the air. The slower the air,
the higher the pressure differential will be between the
cylinder and the manifold. More pressure differential =
MORE FLOW!!! :) But larger is NOT always better... it's a
balance act. Hense, a properly scienced intake manifold.
I've seen a lot of the internal pictures of Toms intake and
considering it's on a stock lower plenum, it's quite good!
Petz #3
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