Intake manifold construction, intercoolers

[Bruce]

But, like everything else there are upsides and downsides.
Them fancy *new* things really look great on paper, and in some ways are a
good thing.  But let us also remember your port(s) sure take a hit on
surface area.  Then we get into boundary layers and other complications,
like the pockets become smaller and so the air has to do even more *bending*
to snake around the valve stem/guide to get to the camber.
  Just to play devils advocate here:
    Is it really an advantage at normal operating conditions?.  Theory would
say so, but in actual practice with all the glump and carbon deposits that
accumulate, what is the real truth?.  Is it even a matter of flow?, can it
be the increased exposure of the pre intake valve pocket area to more/better
back flow from the exhaust valve opening, better atomizing things, that is
what the real advantage is?.  If so then a 3 valve arrangement might as well
be as good as a 4.  Seems like there are some 3 valve designs that work
raher well, and the 5 valve version Ferrari uses sounds good in that
reguard.  But, again we're drifting away from the turbo issue.  With the
increased heat of the EGT (as referrenced to the events at valve overlap) is
this even a true factor?.   With the turbo, it's acting a huge capacitor on
the exhuast gases, and so it might be generating some more effective back
flow at the overlap events.

Bottom line is everything is a matter of compromises, it's just which ones
you want to make.

Bruce
   Sleepy yawned as he was reading this and Doc thought he said *which cake
do you want to make*, so now they have the floor and eggs out, geesh,
another cooking adventure.


Brutal snippage

> Many engines use multi-valve arrangements to increase flow area
> Craig Dotson

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