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Registered
Join Date: Jun 2009
Posts: 1,241
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Rod bearing/bolt life
I have approx 15 hrs on a track motor. Shifts at 72-7500 rpm, 10.5 to 1 compression ratio. Stock rods with ARP bolts and GT3 rod bearings. What is the refresh frequency on a track engine. Thanks, Bob
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Registered
Join Date: Jan 2003
Location: Langley,B.C.
Posts: 12,002
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What motor?
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Turn3 Autosport- Full Service and Race Prep www.turn3autosport.com 997 S 4.0, Cayman S 3.8, Cayenne Turbo, Macan Turbo, 69 911, Mini R53 JCW , RADICAL SR3 |
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Registered
Join Date: Jun 2009
Posts: 1,241
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Right, 78 911 3.0 aircooled
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(man/dude)
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Unless it's a highly competitive class I would just keep an eye on the oil and leakdown numbers and run it till it shows symptoms of a problem.
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Ingenieur
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It’s all about the over-revs buddy. Botched downshifts. I would consider a hard 7200 rev limit, and a max RPM telltale to keep an eye on those. Force on the bolts goes up with the square of the speed: force = RPM^2. No hard and fast rule on how many 7500 RPM trips it has in it, but the unloaded condition (downshifts) is the thing to count, not hours when it comes to rod bolts.
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