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Old 03-13-2008, 06:57 AM
Blown353 Blown353 is offline
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Quote:
Originally Posted by Silver69Camaro View Post
With that mentality, you might was well go for a 4" driveshaft. But it's only money.
LOL! However some of us guys with long single driveshafts actually did the math and found out that a 4" driveshaft was necessary to keep a comfortable margin away from hitting the critical speed of the shaft at the speeds the car can and occasionally attains. Might as well spec all your parts to be safe at the maximum operating capability of the vehicle!

With my combination I found that I was within 150 rpm of the critical speed of a Mark Williams 3.5" aluminum driveshaft at the top of 4th gear, which I do hit every now and again. 150rpm is NOT a comfortable "safety margin" for me especially when it comes to something like critical speed which can and does have very dangerous consequences. A 3.5" Aluminum MMC shaft had about a 700rpm margin, and a 4" aluminum shaft had about a 850 rpm margin. The prices were all very similar so I chose what would give me the biggest margin of safety.
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Old setup: Procharged/intercooled/EFI 353 SBC, TKO, ATS/SPC/Global West suspension, C6 brakes & hydroboost.
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Last edited by Blown353; 03-13-2008 at 07:02 AM.
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