cam degreeing

[Moparmatt72]

Okay so I know you go 0.050 on both sides of the lobe then you add the two numbers and divide by 2, what do I do with that number afterward? Sry its my first time to degree a cam. My cam card says my degree is 108 but will still degree to double check.

Thanks

 

[IQ52]

Here you go, complete instructions. http://www.compcams.com/v002/Instructions/Files/145.pdf

 

[Cranky]

Should you degree your new cam?
"It isn’t absolutely necessary to degree the cam for the engine to run efficiently. COMP Cams® grinds most of its High Energy™, Magnum, and Xtreme Energy™ Cams four degrees advanced. This positions the camshaft for the best street performance. However, to assure maximum performance it is recommended to degree the cam. The purpose of degreeing a camshaft is to correct the errors and tolerances in the machining processes of the engine that can affect camshaft timing. COMP Cams® suggests the intake centerline method as the most simple, quick, and efficient way to degree a new camshaft. Instructions for degreeing can be found later in this booklet."

I think it's absolutely necessary just because of what this article states...to correct errors and tolerances in the machining process!!!!!! I've even had Comp cams that were ground off center of the locating dowel pin! It amazes me that they would even say it's not absolutely necessary to do this.

 

[Cranky]

Add the 2 numbers together and divide by 2. That number will be the location of maximum lift
of the intake lobe in relation to the crank and piston. This is the intake centerline. For example:
The first degree wheel reading was 96 degrees. The second reading was 116 degrees. These
two numbers (96 + 116) added together will be 212. 212 divided by 2 will equal 106. Your
actual intake centerline is 106 degrees. Reference back to your cam spec card and see what the
recommended intake centerline is

 

[Moparmatt72]

Thanks to you both, I know my cam according to isky the centerline is 108, its their 292 mega cam. Ill still check this once I get the cam installed.

 

[383man]

Also remember the Lobe Seperation Angle is not always the recomended Installed Centerline. The cam in my 63 is ground on a 110 LSA which you can not change but they recomended to install the cam on a 106 centerline. Ron

 

[Moparmatt72]

Ron that's interesting. Yea ill just have to see where it come out on the cam and go from there, hopefully will get to this part this weekend.

 

[Cranky]

LSA and intake center line is sometimes mistaken for the same thing but it's not the same but 383man is right. The LSA is how far apart the intake lobe CL is ground from the exhaust CL. You can plot that on the degree wheel too to make sure you have the cam is as advertised and some fanatics will check every cylinder. I've been known to check a couple of different holes....just depends on how deep I am into a build. Also, some cam manufactures won't bother to list when the events happen...ie, when the intake opens and closes etc because you can change all that depending on where you place the intake center line but I like to know what they are based on their recommended installed center line.

 

[383man]

I should have clarified more that my cam is in on a 106 intake centerline. And as was stated the LSA is the difference in degrees between the intake and exhaust lobe centerlines. Ron

 

[lewtot184]

if it were me i'd record the numbers at .300 lobe lift on the opening and closing sides and then divide by 2.

 

[67 B-body]

Mr Kofell of Kofells Place "The Flinstone Flyer" said he used to just place a straight edge across the lifters and role the engine untill it lays flat across both. Of course you would want this at TDC, but he said this has always got him close enough to perfect.
I guess if you want to dial indicate things, then this could be a good quick check.

 

[Mr Roadrunner]

Just finished a 383 for my dad for a 78 power wagon he is redoing. We used a Hughes engines hydraulic and it degreed in way off. Dave at Hughes advised me to get the Intake valve closing point as close to the card as possible and not worry about centerline so much. His point was that when the intake valve closes, the cylinder starts to build compression (power). I was able to "nail" the closing point, and after going back and checking centerline, I found it to be 1.5 deg. off. Also just to add to someones comment about machining errors, The crank key, timing chain, and camshaft all could be the culprit, not just the cam. 1 degree off, you will never see a performance difference, 2 degrees maybe a little, and 3 degrees definitely needs corrected.

 

[Moparmatt72]

Thanks all for the tons of info, ill post up what I get and can always change if need to won't be in the car till I get either the old ones done or just buy eddys or 440source for a little more power