cam lift?

[Anonymous]

I have three cams,infront of me(not actually at the moment ) one is know lift of 480,one which (according to specifications) is 540, and the other is the one I have just removed from my engine. Using a micrometer I measured a lobe on the known cam, I then compared this to the others,the "540" lift cam was about 10 thou bigger,the cam I removed from my engine was 20 thou bigger still,am I missing something here surely the "540" would measure approx 40 thou more( 1.5 rockers)and if the cam that came out of my car was nearly 600 lift,it would have been at the least "lumpy" which it was`nt help

[Mick70RR]

You need to measure the difference between the maximum and minimum measurements of the lobe. This is the cam lift, multiply this by 1.5 to get the valve lift.

[Dave-R]

If you are asking how do you measure lift you have to first measure what the base circle diameter is. Then measure the max diameter of the lobe.

Then you take away the base circle diameter from the max diameter and that leaves you with the lobe height.

Now you take that measurement and multiply by 1.5 to get the valve lift.

Do it that way and it should all add up.

[Dave-R]

Beaten to it by Mick.

Remember that lift is not a good indication of cam size. Duration is what sets the rpm range (how "big" a cam it is).

[Kev]

Yah! It's all to do with the angle of the dangle; Valve lift=Easy. How the cam works=?Voodoo.

[Anonymous]

thanks everyone,I`ll re measure it later

[Rich]

Measure it?? You will need to borrow Kev`s voodoo-ometer.Also usefull when delving into an auto box.Cause we all know whats in there!! :gearhuh:

[Anonymous]

good un! I`m just going to compare the cams Ive got ,I bought the cam off widman ,but I was told a comp cams 292h would be better,now I`ve stripped engine & found ( I think) an after market cam & compared the two ,the one I took out has (it seems) more lift! i`m