degreeing cam

[Big_Al]

I've never degreed a cam before. I'm getting kind of confused. Lol I was calculating my intake centerline and I came up with 110. On my sheet it says that with 110 centerline my cam is 4 degrees advanced. Will that change the 114 lsa of my cam?

 

[67Dart273]

I could type a whole book, and I'm really not trynna be smart. If you google this, there are several videos on YouTube, etc, from places like Comp Cams as well as online documents, pdf, etc


This insists on posting wrong, put in http://www. and then put in

compcams.com/technical/instructions/files/145.pdf

[ame="https://www.youtube.com/watch?v=7cNoVRLb73c"]Quick Tech Video: How to Degree Your COMP Cams® Camshaft - YouTube[/ame]

 

[madscientist]

It's ground on a 114 LSA (why I'll never know, unless you like the old 30-30 style of cams but that's on you) and it's 4 degrees advanced.

Leave it alone, it's where the cam grinder wanted it.

 

[Big_Al]

So 110 centerline is fine? It's for a turbo motor

 

[AJ/FormS]

The LSA is set by the grinder at the time of manufacture. You cannot change it, in the field.

 

[nm9stheham]

Moving a single cam advanced or retarded does not change LSA; those are fixed. You can only change LSA in the field with a dual cam setup where intake and exhaust cams are separately settable.

I recently looked at some cams for turbo use and a few degrees advance seems pretty common. So if you install it with the ICA at 110 degrees, you will be at that 4 degrees of advance. You can do similar things with a turbo cam as with a NA cam; advance helps bottom end torque and retard helps top end. Since getting low RPM cylinder pressures up helps exhaust pulse pressure, and that helps the turbo to spool up, I suspect (guess?) that is why a bit of advance is common.

You sure this cam is ground specifically FOR a turbo motor? The durations seem on the long side for that.

 

[Bakerlite]

I'll explain it a bit better to you , rather than just telling you it's "Fixed" :roll:
LSA is Lobe Separation Angle. It is the number of degrees between the centerline of the intake and exhaust lobe of the cam . Since the cam is made as one solid piece, then this number is set into the cam when the lobes are ground.
LCA Lobe Center Angle , is the center line of the intake lobe ( the very tip of the cam lobe nose) in relation the the angle of your crankshaft, thus timing the cam to the crank.
You can also set the timing using Intake lift at TDC Top Dead Center, if they give you the number to do it. That way you don't even need a degree wheel. Just a piston stop and a dial gauge on the valve retainer or lifter..

 

[Rapid Robert]

keep reading up on it over and over as it is a confusing subject & when you grasp it it's fairly simple but you wont believe that till you get there but you will. If the intake cam lobe "peak" reaches max lift at only 104 degrees past TDC as opposed to a bit later at say 108 degrees then the 104 position is more "advanced", hope that helps. As said LCA is how far an intake peak and an exhaust peak are away from each other on the stick & that is in cam degrees and adv/ret (cam phasing in relation to crank position) which you change with the timing gears is in crank degrees, as said it ain't easy (till you get there), took me a month of reading!

 

[Bakerlite]

Robert, your mean LSA.

 

[Rapid Robert]

Thanks bro!

 

[Bakerlite]

I know, it's easy to do and embarrassing when you do it during a conversation with a customer #-o