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Re: misaligned cam

To: <>
Subject: Re: misaligned cam
From: "Jeff Fayne" <>
Date: Thu, 13 Sep 2001 07:19:15 -0500
> Yes it would, just badly.  In general, a cam can be indexed (re-timed) by
> up to 6 degrees either way (+/- 6) from its nominal specification (equal
> +/- 12 degrees at the crankshaft).
> Retarding the cam timing will move the torque curve up the rev range,
> giving the engine more torque at higher speed, which may be good for a
> racing engine that spends very little time in the low speed range.  This
> increase in high end torque is a result of holding the intake valve open
> longer to allow the greatest charge of air in the cylinder before closing
> the valve for the compression stroke.
> Advancing the cam timing will move the torque curve down the rev range,
> giving the engine better torque at lower speed, which may be good for a
> driven around town a lot, and spending most of its running tine at lower

Here's another link that will help:

I was looking at this site the other day, what struck me as odd was this
comment (from the same FAQ):

"How does advancing or retarding the camshafts position in the engine
affect performance?

Advancing the cam will shift the basic RPM range downward. Four degrees of
advance (from the original position) will cause the power range to start
approximately 200 RPM sooner. Retarding it this same amount will move the
power upward approximately 200 RPM."

I would of thought +/- 4 degrees would cause a larger shift in the power
band than 200 rpm. Perhaps that should be 200rpm/1 degree?



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