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TheMentat TheMentat is offline
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Join Date: Dec 2004
Location: Ocean Park, BC
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Quote:
Originally Posted by jcge View Post
According to Mezger's 917 tech paper...

"The cooling blower is arranged horizontally above the
engine. It has a diameter of 330 mrn (13 in) and supplies
the cooling air for the engine at a rate of approximately
2400 l/s at the rated engine performance. The blower is
driven via bevel gears at a ratio of 17: 19 of engine speed.
As already mentioned, at maximum engine power the
power input to the blower is 17 hp, i.e. 2.7 per cent of the
engine performance. Of the entire cooling air volume
65 per cent is used to cool the cylinder heads and 35 per
cent for the cylinders."

He cites the 3 litre 8 cylinder race engine (908) as absorbing 14hp.
I'd imagine that the horizontal fans in race applications are geared to push a lot more air at a given RPM, hence the seemingly high numbers...
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Old 03-12-2009, 09:04 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #12 (permalink)