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WERK I WERK I is online now
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Join Date: Jan 2003
Location: Wisconsin
Posts: 3,291
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Quote:
Originally Posted by totle View Post
I did send one piston to JB racing, and had JE custom made the new pistons
Not wishing to stir up a hornet's nest here, but those pistons were doomed to fail. You're right about the top ring land being too close to the valve-cut crown. But, if you look at the area where the fracture occurred, there is very little material at the outer edge of the valve cut to the interior section of the ring land, maybe several millimeter's? Once that cracked started, the area would start to lift........BANG! Valve contact., catastrophic failure.

With all due respect to JB Racing, that was NOT caused by detonation. That is a piston design flaw.

Totle, I know you're not trying to place blame, but illustrate an engine failure. I respect that, just thought you should know a more likely scenario.

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Dave
'85 930 Factory Special Wishes Flachbau
Werk I Zuffenhausen 3.3l/330BHP Engine with Sonderwunsch Cams, FabSpeed Headers, Kokeln IC, Twin Plugged Electromotive Crankfire, Tial Wastegate(0.8 Bar), K27 Hybrid Turbo, Ruf Twin-tip Muffler, Fikse FM-5's 8&10x17, 8:41 R&P
Old 10-09-2011, 11:43 AM
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