Degreeing Cam Needed???

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RPM

RPM

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I am just curious what some of you think.
When installing a cam on a small block with hydraulic lifters and stock rockers,
non-adjustable, and running a single key timing set straight up, is it really neccesary to centerline the cam???? I have always done it and it always comes out correct, but, is it needed? Seems if nothing is adjustable and everything is new ots going to be pretty darned close. I am curious becaus I am at that stage of my car, but the the guy with the degree wheel is going to be away for a while. He said it wasnt really needed, but more a precautinary measure. It makes sense to me that it doesnt need done, but then again I dont want to screw up. Agina this is not a 500 HP motor or anything like that....probably tootin around 380HP.

any thoughts much appreciated!!!

-RPM
 
A motor will run without degreeing the cam so I would say it is not needed. But if you want to make sure a motor will run to its full potential then I would say that you should degree your cam.
 
I would just consider it insurance. I would hate to find out it was wrong after the motor was installed! I guess it just depends on what your time is worth.
 
If your really trying to make HP, then yes, if it's a small cam, No. But it does help alot in getting the most out of it.
By small cam, I mean under 280* advertised. Though this is very small by compare to race cams that can be as large as 280* @ .050.
If you look at duration @ .050, a small cam example would be under 220*.
Like I said, to get the most out of it. A small cam like this may see 5 hp when in as perscibed. But the big cam example could be 50HP.
On the street, 5 is nothing. On the track, it's a win or loss.
 
Everyone above is right, It's really not needed any more on a smaller cam. Back in the early '80's I used to see some cams off by 4 degrees or more, but the last one I installed (a crane) was dead on when I checked it. Fords used to use a retarded cam gear back in the day for emmisions reasons, and if you used a parts store replacement you were asking for trouble. By the way, MP offers offset keys in 1 degree increments giving you the ability dial your cam right in or add advance with a single keyway gear set.
 
Here's my 2 cents why it should be checked. If you check it and determine where it is at, after the motor is running, if you're not satisfied with the performance you don't have in the back of your mind, I wonder if the cam's in straight up. I have put them in and seen the cam be off 3 degrees retarded. In that instance, I left it alone and ran it, figuring it would have a little better top end. I wasn't happy with it and ended up advancing it 6 degrees so it ended up advanced 3 degrees and it ran a lot better. Its just that its so much easier when the motor is on the stand.

don
 
hi, it's not so much the cam is off, but the gears can be and are indexed wrong. If they are off, then cam will not be installed correctly. I have seen this before. motor has no power, etc. I have seen a cam gear off as much as 13 degrees. I wouldn't trust the gears being correct. it is better to check it now, once in car, way more work, expense.
 
Twice I have seen things be off so I always check it just to be sure. Once the cam (a Comp cam) was ground wrong and the other time the timing set was indexed wrong by 2 whole teeth.
 
To be honest, I have no faith in marketing. You degree a cam to eliminate errors. Errors in machining the cam, errors or wide tolerances on the timing set, the keyways, and/or the indexing of the crank keyway. In most cases, you will have to chnge the centerline to get it where the cam companies say each one should be run. Very generally, I've found Comp to be within 2* every time, no matter how big or small, or type of engine, of the spec given on the matched cam card. Crane, is generally within 2-3*. Custom cams are within 1-2*, and the favorite Mopar Performance are a roll of the dice. I've had a couple be dead on, and most are between 4-10* off from the cam cards.(disgustingly bad, IMO..hence me not running them in most cases) An example from last week: Engine is a B block 451, factory crank, Comp 270H cam, and Comp roller timing set. Card says 106* recommended installed center line. It degreed at 108*. Not bad, but not what the card says to run it at (Which I agreed with). It may have been teh timing set off a degree, the cam grind off a degree. Would the typical driver notice it? No. But to me, it's not what the cam grinder wants, and it can sacrifice measurable power and in this case, may effect idle quality and vaccum. This is for a car with power brakes, and A/C. It'ssupposed to look and sound like a stock 383, or very close. So, IMO, it makes a difference. I drilled the gear, and installed the 2* bushing. It's at 106 now. Degreeing is one of those things that makes some cars run like mad, and some never quite feel right. It MUST be done when using MP cams, and be prepared to use offset keyways/bushings on the crank and cam becuase they can be that bad. My $.02 anyway...
 
Based on the responses, decided to degree the cam yet? My .02 worth is same as most everybody else. I'd degree the cam for peace of mind. Everyone I have checked has been off by at least a couple of degrees. If your building a performance engine, why not spend a little extra effort for the most performance.
 
well thanks everyone, i am definately sticking with degreeing in the cam.
The engine is not on the stand though, I am just performing a cam swap, I may have failed to mention that, but, either way, I will still degree the cam to make sure she is correct. By the way its Comps XE268 cam.

thanks again!

-RPM
 
If you dont already have one, Moroso makes a 10" (IIRC) degree wheel that works in tight engine bays...lol. Saves a lot of time if it's small enough to clear the K frame, even if the smaller diameter makes for a slightly less accurate read.
 
RPM, I recently bought a used XE 268 to put in my 340. It suppossedly has about 3000 miles on it, so I took a chance. A friend of mine put one in his early 340 and said he could tell no difference from the stock cam, on the street. It would be interesting for you to let us know if you can tell tell a big difference when you get yours running, please let me know. thanks walt
 
put a hughes cam in and got 110 degrees i centerlined it to 103 which the time card says. is this common?? or should i be worried?
 
h340 said:
put a hughes cam in and got 110 degrees i centerlined it to 103 which the time card says. is this common?? or should i be worried?
Click to expand...

Wow man you resurrected an old thread!! Read all the above posts and you'll find your answer. It's not normal to be 7 degrees off at all. If you have another timing chain set I'd try it and see how it comes out with it. I've seen more variance in chain sets than cams. If a different chain set shows the same I'd guess the cam is ground wrong. It's probably ground on a 110 centerline. Maybe they forgot to add in the advance. That would make me wonder if the rest of the cam is right.
 
h340 said:
put a hughes cam in and got 110 degrees i centerlined it to 103 which the time card says. is this common?? or should i be worried?
Click to expand...

BTW: It's much better to start a new thread than to tag onto an old one like this. These threads notify each poster when a new post is made but when they get so old it doesn't do that any more. I just happen to come across it and see your post.
 
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