Cam Lobe Base Circle Sizing

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Aug 22, 2013 | 11:12 AM

TurbopigB4C

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From: Hemet

Cam Lobe Base Circle Sizing

Are the only Comp Cam lobes that have a different than stock base circle size the LSL lobes?

Aug 22, 2013 | 11:42 AM

PREDATOR-Z

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From: BFE

https://ls1tech.com/forums/generatio...cam-guide.html

Aug 22, 2013 | 01:45 PM

TurbopigB4C

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From: Hemet

I did not see anything on base circle sizing for the different comp lobes, thats why I posted. Sorry if I missed it but does anyone know specifically if XFI lobes on a stock ls1 longblock would be 7.400" pushrods?

Aug 22, 2013 | 02:56 PM

PREDATOR-Z

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From: BFE

That you'll need to measure for push-rod length and correct lifter pre-load.

Aug 23, 2013 | 01:02 AM

01ssreda4

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From: Turnin' Wrenches Infractions: 005

Always measure, and theoretically all aftermarket cams require longer pushrods because they start as stock cores, they are regrinded, and re-hardened. Meaning they all should have smaller then stock base circles.

Aug 23, 2013 | 12:31 PM

TurbopigB4C

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From: Hemet

According to Comp tech lines they say that they definitely preach measuring but most stock ls1 engines will be 7.400" for cams with lift less than .600 and 7.425" for cams with above .600.

Aug 23, 2013 | 05:25 PM

badazz81z28

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Consider this....how do you expect to install a cam with such a high lift with a stock base? It wont physically go in the engine without a smaller base.

Don't listen to anyone about PR length, you have to check your self for your engine. I'm sure we all get sick of engine problems related to PR length or the questions asking...