while digesting all the responses to my
questions about EFI I came across this article, http://www.neverworld.net/socalnetscum/files/tech/CarbShoot.pdf ,
on a bench flow test for Harley carbs. what surprised me was how finicky
and unpredictable any modifications were. it also struck me how dirt
simple the Harley intake was, a "Y" all of a few inches long, yet it dropped
flow performance 20-30%! this makes me wonder how the intakes we fabricate
would measure up, with all the bends, joints, AL to rubber to AL and such.
no wonder my Lycoming can run 150 degrees different between cylinders, and that
polishing ports makes a difference.
so, I can easily see the point of using software
to tune the final design vs. trying different mechanical combinations.
that doesn't address air flow routes thru the intake manifold tho, just fixes
the individual air/fuel mixtures arriving at each rotor.
next wonderment - why are exhaust manifolds
typically designed to get larger dia. as more tubes attach downstream (as
with the waste plumbing in buildings), when, in reality, the flow is thru only
one tube at a time? kevin (turrentine renesis coming
soon!)
|