Degreeing a camshaft...uhoh?

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Um, I'm concerned. I have never heard of degreeing a cam before reading a few posts here lately. That's not what concerns me. I'm a novice builder (duh). What concerns me is when we (me and my good buddy with LOTS more engine building knowledge than I have) reassembled the motor, we didn't do anything like what i have read:

http://www.hotrodder.com/kwkride/degree.html

We just slid the cam in and set the cam and crank gears to match their marks with #1 on TDC. Is this bad? :shock: Could THIS be why I've been having issues with my rockers and low compression on a couple of cylinders?! :shock: :shock: Is it possible that even if we didn't do it just right, we got lucky because the car really runs pretty nice and quick (when the rockers studs aren't breaking off :oops: )

I didn't get a "cam card" as I've heard them referred to with mine from Mike. All of his cam specs are on his site. Is that all that's on the card?
 
pedal2themetal45":jof0v41q said:
HI
I'm not sue but I think this is just to check the cam to make sure it was ground right.. :?:
tim

yes and no i think...

depending on where your cam is set (advanced or retarded) will affect power
for example, the stock big six cam is retarded 4 degrees, when you set it to 0 degrees you get a decent bump in power

it's why they make timing gears that are adjustable to one degree
 
So, assuming there were no machining errors when the cam was created, how do I know where the cam is set? Since I set everything up at TDC with the marks lined up, is that 0 (again, assuming the machining was balls-on)?
 
There's no way of knowing that you installed it correctly unless you have the cam card and you degree the cam. However, if you have installed the cam "straight up" (0 degrees) then you'll be fine. I've never had a problem with any cam that I've installed staight up!
FWIW.....
We degreed Kelly's cam (a 274 from FSPP) and due to the fact that nobody had a multi-indexed timing chain for a 250, or even a '69 style one, we used a '78 style one that is 6 degrees retarded. Did some math and determined that each sprocket tooth was worth 8 degrees of rotation. So I installed it 1 tooth off so that we've got 2 degrees cam timing advance. :wink:
It's a proven fact that an advanced cam is worth some power everywhere under the torque curve.
Will
 
So, with that said, if I installed it straight up, i could be sacrificing potential power gains then, right? If I wanted to advance it some, I'd need to just pull the front to expose the timing set, remove the chain, and roll the cam the desired amount before remounting the chain...right?
 
Not really.

Advancing and retarding the cam really just shift the power curve, it doesn't really increase/decrease the power. IIRC, advancing the cam will shift the power curve to lower RPMs but you'll sacrifice on the other side. I may have the shift direction wrong.

I installed mine straight up with no problems at all. Runs great.

Slade
 
Bryce, you have a FSPP camshaft ground by clay smith. These cams are ground with a split overlap. They are not advanced or retarded.
I believe the competetion cams are ground with a 4 degree advance for more low end power , but less top end. for normal street driving they work great.
If i pull my engine down I may advance my FSPP 264 cam 4 degrees. this will give me more lower end. May cut some top end power, just will have to try it.
When I degreed my camshaft in it was within 1 degree using the intake lobe center method. That is awsome, most of the cams I install are off more than that. William
 
Thanks William. I have MORE top end than I could want, but you never have enough at the bottom! Once I get the valve train issues worked out and the new tranny in, I may investigate this further.

Thanks again all
 
Bryce, you might want to advance your cam 4 degrees & give it a try. It will purk up you bottom end power. William
 
Thanks. Is it just as simple as I described above or is there more to it? Are the SPECIFIC directions anywhere?
 
Bryce, just remove the timing chain cover & place the crankshaft gear to +4 & put it back together. William
 
"Degreeing" a cam is really just another step in "blueprinting" an engine to make sure that everything is exactly right. I suspect that 99% of all rebuilt engines do not get the cams degreed in, and virtually all brand new engines don't either, they just accept the factory tolerances and nobody knows the difference. When you want to squeeze every bit of performance out of an engine it is a very important step, but your Aunt Tillie's grocery getter probably won't care.
Joe
 
I bought what was basically a 200 short block off a guy in another forum. He said the PO had done a "stock" rebuild; you could still see the hone marks on the cylinders. Well I degreed the 'stock" cam in it (it was my first time degreeing a cam, so I need the practice) and found out that the lift at 0.050 was 150 degrees. So the point it to check and verify what these manufacturers put in boxes and sell you. More than likely the part is per spec, but it never hurts to check. Usually all it costs is time.
 
63DropTop":1htl25g0 said:
HEY! This aint no Aunt Tillie Grocery Getter!

LOL! :roll:

:oops: :oops: That didn't read quite the way I meant it, sorry :oops: I wasn't referring to YOUR engine but rather AUNT TILLIE's engine.
Joe
 
Hey, at least aunt tillie will get to the grocery store real fast. :D :lol: William
 
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