Otto: I don't dispute the HP gains and I am a dry-sump proponent. However,
me thinks your explanation needs more explaining.
If one piston is being "sucked" down then its opposite twin (the piston that
is going up) is being "sucked" or held back from going up. There is no net
gain in torque.
Further, the down piston is not pumping pressure. How could it? The sister
piston going UP is increasing the crankcase volume at the very same time.
The displacement volume always remains CONSTANT, therefore, no pressure
delta from piston travel. Yes, there are pumping losses from high velocity
travel through dense air. With a high altitude crankcase these losses are
less and result in more HP. I suspect all the good things you said about
ring sealing, blow-by, oil scraping, etc. results in "free" hp from your
$1,200 dry-sump. -Elon
PS: Sorry, I am leaving cyber space for a week. I'm not being rude.I just
won't see a reply after this email is sent.
From: Askotto@aol.com Date: Thu, 19 Oct 2006 13:37:46 EDT
(snip. . . )The dry sump system on the other hand creates about 15 inches of
vacuum in
the crankcase. This "sucks" the pistons down the bore. This is where the HP
gains are actually realized.
There is also the theory that the vacuum increases ring seal against the
cylinder walls and keeps oil from squeezing out the gaskets, seals, etc.
Also
with oil scavenging in the lifter valley, you don't have oil coming down to
get
wound up in the crankshaft. The oil hitting the crankshaft causes HP losses.
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