Thread: Comp cams??
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Old 10-24-2001, 08:19 AM
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CobraEd CobraEd is offline
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Lee, One of the most overlooked elements of a cam is lobe separation. Often the catalogues don't even show this, but it is very important.


Here are the major elements of camshaft specifications:

Lift: affects torque across the board. More is better. Does not affect idle.

Overall duration: higher overall duration increases torque in the upper rpm at the expense of lower rpm. High duration affects idle quality.

Acceleration rate (lift @ .050) higher rate tends to increase torque across the board. Does not affect idle. puts a strain on the whole valve train if too high.

Lobe separation: the overall separation in degrees between the intake and exhast events. Low lobe separation (106-108) Increases peak torque and horsepower. Typically used in a racing cam. Causes a lopy idle even in a cam with moderate overall duration that would otherwise have a smooth idle. High lobe separation (110-114) is good on emissions, smooth idle, produces a broader flatter torque curve for around town driving.

Phew!!

Also, here is a good web site with terriffic cam information for the 302/351 engine. Although not the cleveland, the information is very comprehensive and could help you with your process.

http://www.geocities.com/MotorCity/T.../cams_hyd.html

If you want to discuss cam selection email me and I'll give you my number.

Ed
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Last edited by CobraEd; 10-24-2001 at 11:24 AM..
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