how do i check for performance cam?

[ben]

i have a few different heads and i was wandering how i check the cams to see if any are a performance cam. do i use a micrometer and check the lobe length or is there a simpler cheaper way? what would the stock lobe length be? thanks for any info.

[ToddK]

Two easy things you can do are look at the front of the cam for any specs stamped into it, and measure the lift at the lobes. Once you remove the valve cover, shine a flashlight down the front of the motor. Where the sprocket mounts to the front of the cam there is usualy something stamped into the flat part of the cam on aftermarket cams. The other easy thing is to take ruler or micrometer and measure how much taller the highest point of cam lobe is campared to the flat part. You can also check lobe centers, and duration, but you should have a degee wheel. I just bought a 75 2002 at auction for $55.00. It was in a very dark building and I realy couldn't get a good look at it. I only bought it because it had twin Webers. Once I got it home I realized they were 45 dcoes. Compression test yielded 185psi. Popped the valve cover to find custom rockers and a cam marked SERRA 300. Checking the lift showed that it was 20% more than stock. We got the thing running. Motor will be heading to my engine builder for a complete inventory and a refresh as called for. It pays to check.

[Guest Anonymous]

regrinds usuall do not have a raised heel ( 180 from nose or high point of cam) hell usually same same as shaft. stock has araised heel

[TobyB]

and serious regrinds recess the lobe below the casting of the cam's shaft.

t

[ben]

thanks for the info. are there any more of those 55 dollar deals around?