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removeing shims ??

removeing shims ??

Old 06-12-2009, 11:50 PM
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Default removeing shims ??

is it smart or silly to remove a shim ,on todays hi powered engines to get a bit more grunt ,running a 21 cobra axe rossi and wanted a bit more push for my truggy can i remove a shim for easy fix or no ??
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Old 06-13-2009, 12:17 AM
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I'm guessing it would be like advancing the timing on your car without running higher octane. (detonation/pre-ignition)

I'm not positive, so i'd wait for further comments from other guys.
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Old 06-13-2009, 08:53 AM
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Ive always been told to use the proper shimming for the type of fuel you are running so this would go against the grain. I dont know the complete principal for this but it has to do with detination of the fuel. It sounds good but Im gonna stick with what the engine builders say.

.60 = 20 % fuel
.70 = 25 % fuel
.80 = 30 % fuel
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Old 06-13-2009, 08:55 AM
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Your pipe combo should fix the problem.
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Old 06-13-2009, 09:27 AM
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on my OS speed, removing shim gave more bottom, but lost some top end rpm
and ran hotter.

when tuned right, overall power was same
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