Theo, David, Tim,
I just love all this bench racing. Of course, we all know the numbers tend
to get a little inflated - Right? 15-25HP in the pan, another 15 in the
water pump, and then a bunch more is lost in the drive train. It's a wonder
there's anything left at the wheels! Now, as a physicist, the first thing I
ask is Where's all that energy going? Into heat, of course. Putting 15HP
into 7 quarts of oil is, frankly, a little hard to believe. But, no
question, your oil does get hot running 6-7,000 rpm - I just don't think
it's 15HP worth; maybe I'd believe 5.
If your motor only puts out 150HP, then 15HP is 10% - a reasonably big deal.
But it's less than 3% out of 550HP. The thing that hasn't been mentioned
though, and I think needs to be, is the issue of air in the oil, which is
greatly to be avoided and which a windage tray, or better still, a dry sump
will prevent.
By the way, I probably spend 8-12 hours with a die grinder polishing my
crank just to reduce the air and oil friction, so I obviously do put some
credence in this notion. I don't really know how much it helped - if any -
but it sure looks bitchin. In order of importance the pan needs volume
(>7Q), baffles, and last, a windage tray. If you're buying a pan with the
first two, then it's probably only a few bucks more to include a windage
tray so you may as well include it, even if it's only 5HP, but definitely
cooler oil and less entrapped air to abuse the bearings.
Bob
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