Originally Posted by A727Tflite
Seems some people are confused between the meaning of LSA and Centerline.


The only confusion I see in this thread is Larry Sheppards 50 year old chart. Centerline is not ground into the cam, it is determined at assembly. The column labeled Centerline should be labeled Lobe Separation Angle and then he probably could have added another column labeled Recommended Installed Intake Centerline.

Quote
You can change the installed centerline - you can’t change the LSA.

I doubt any manufacturer advises the user to install the cam using LSA.


True but if the cam has symmetrical lobes as I am sure all of these cams do then if installed Straight Up the ICL will be the same as the LSA. In practice most people will install these cams advanced at least 4deg. resulting in an ICL less than the LSA.

At the risk of complicating this more, the Intake closing event is what affects cylinder pressure. When Harrold Brookshire was grinding NASCAR cams he didn't even tell the teams ICL and LSA. Probably because they are not really relevant with nonsymmetrical lobes.

Last edited by GomangoCuda; 01/20/24 07:24 PM.
In theory, there is no difference between theory and practice. In practice, there is.