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Scott Clarke Scott Clarke is offline
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Join Date: Apr 2002
Location: Eugene, Oregon
Posts: 1,115
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It is a misconception that long stroke motors produce more torque than short stroke motors. This misconception is based on the fact that long stroke motors are often tuned to produce increased torque as a route to horsepower because the alternative (higher RPMs) isn't possible due to unacceptably high piston speeds. In order to realize the potential for the theoretical increase of power possible with a short stroke engine, the potential for higher rev capacity must be realized. This means that the valve train must be capable of such RPMs, and that the induction track will have the capacity to move air into the engine while not forcing the air to move at unreasonable speeds. So, for a Porsche engine, the long and the sort of it is (ha ha), either approach is fine. Porsche has never really made a "long stroke" engine anyway, just short and shorter. It's relative. Other factors seem to be of more consequence (availability of pistons and cylinders, camshafts, etc). Me? I'm building a short stroke because I like the IDEA of it, and it was a good way to go given the parts that I started with.
-Scott
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'70 911E short stroke 2.5 MFI. Sold
'56 Cliff May Prefab
Old 12-12-2003, 08:27 AM
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