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Old 06-22-2012, 01:46 PM
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Tom Vaught Tom Vaught is offline
Boost Engineer
 
Join Date: Dec 2001
Location: The United States of America
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Food for thought:

Langer turns his engine over 8000 rpm routinely.

I saw Bryan's (Goatracer's) Engine go to 8500 at least 26 times on Holbrook's dyno without any issue.

The Keen's used to run 9000 rpm (WITH BOOST).

If you take a NA Engine and add Boost, typically the cylinder pressures DO NOT DOUBLE. You add 15-20 psi of boost and the cylinder pressure goes up by maybe 7% to 10%. The extra power comes from the extra Mass Flow in the cylinder allowing a longer "push on the piston" every combustion event.

The Inertial Loads are higher (when the engine swaps direction at the top of the overlap stroke) as the rpm increases but we have a lot of guys now running 8000+ rpm without ripping the piston off of the rod.

If you have a quality engine build, (which you have from Uncle Tony) there should be no issues with rpm. Springs, is another story. Springs should be sized for rpm and boost level. A Lot of Boosted Engines out there with guys who could tell you about their springs (as well as the PAC Guys who are the experts).

JMO

Tom Vaught

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