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High Compresion vs. Small Cam - Problems?

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Old 04-27-2004, 02:40 PM
RaptorRacer1's Avatar
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Default High Compresion vs. Small Cam - Problems?

I am using a Hotcams Stage 1 cam and have my head ported by Craycraft. I want to go up to a 11:1 or 12:1 piston, stock bore. I am hesitant to go to a bigger cam because I mostly ride tight woods trails. I need something with real strong bottom end that I can lug around at real low RPMs.

I read in a post by Dynoray (WSHRDSKN's thread about his piston failure) about using high comp. with a small cam - that it can cause really high cylinder pressures. Is this cam/compresion combo ok, or is it recommended to go bigger with the cam?

Thanks guys!

RR1
 
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Old 04-27-2004, 03:15 PM
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Default High Compresion vs. Small Cam - Problems?

I previously ran a Hot Cam stage 1 with a 10.75/1 JE on premium pump gas with 1 small problem. Meaning I heard detonation when pulling out WFO in 3rd gear really working the engine hard. I switched too 1 shade colder spark plug and never heard detonation again. 1 shade colder on the plug is equal too roughly 100 degrees less heat in the combustion chamber.....reducing the potential for detonation. You WILL loose a little bottom end with a larger cam...but maybe thats a good thing. You may not wear out as fast with a little less arm stretching torque. My $.02
Gary
 
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Old 04-27-2004, 03:27 PM
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Default High Compresion vs. Small Cam - Problems?

Its pretty much a trade off... Like in drag racing you dont run a High compression setup with nitrios, superchargers or turbos. You will loose you bottom end with a larger cam. But.. raptors already have that huge grunt on low end so i dont think loosing some inturn for high end will cause that much of a problem.
 
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Old 04-27-2004, 03:39 PM
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Default High Compresion vs. Small Cam - Problems?

I'm running an 11:1 stock bore and a stage 1 cam, its got great low end, I think you'd be happy with it.
 
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