Cam degree

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twayne24365

twayne24365

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hey guys, never had any problems degreeing a cam or having them be far off.
But building this big block ford I’m a little stumped, cam is a Lunati solid roller, 106 centerline, when installed straight up I’m getting 99*, I retarted the crank gear
(9 keyway chain) and got it to 105* is this normal to have to move it so far to get it to spec?
 
twayne24365 said:
hey guys, never had any problems degreeing a cam or having them be far off.
But building this big block ford I’m a little stumped, cam is a Lunati solid roller, 106 centerline, when installed straight up I’m getting 99*, I retarted the crank gear
(9 keyway chain) and got it to 105* is this normal to have to move it so far to get it to spec?
Click to expand...
Simple solution, scrap the Ford and get a Mopar hahaha
 
You’re basically checking the accuracy of the crank key slot, timing chain set and the camshaft. Tolerance stack up could get you that far off as can any error in determining TDC.
 
Big block ford (FE/385) front right hand cylinder is number one.
 
That's a really good observation. Mopars are rarely off by more than a couple; but 4* advance is often ground into the cam so it practically falls in.
In your case, if the cam has no such ground-in advance, then yeah, I could see some additional work required.
 
My 460 was off a few degrees but there are several factors that can alter things in the end other than the make of the motor. If your confident in what your doing then it is what it is but you could ask on 460Ford.com Be specific in what you have, how you have it set up and what not.
 
I've heard that ford retarded the cams in big blocks for emissions purposes or something. Maybe that's part of your problem?
 
1994redram said:
I've heard that ford retarded the cams in big blocks for emissions purposes or something. Maybe that's part of your problem?
Click to expand...
I knew they did that with the drivers of their late model mustangs but it usually doesn’t affect anything unless leaving a car show...
 
dano said:
My 460 was off a few degrees but there are several factors that can alter things in the end other than the make of the motor. If your confident in what your doing then it is what it is but you could ask on 460Ford.com Be specific in what you have, how you have it set up and what not.
Click to expand...
how does the tdc mark on dampener/timing cover check with the tdc you determined?
 
Motor is in short block stage, no damper or chain cover, set T.D.C. with dial indicator. Cam is 110 with 4* ground in for 106 installed,
 
rustycowll69 said:
how does the tdc mark on dampener/timing cover check with the tdc you determined?
Click to expand...

It's been several years since I built my 460 and don't recall. I forget Ford has a sheet metal pointer unlike the 70- newer cast in LA motors. Did you verify the pointer lined up with the damper mark at TDC and is the Damper stock? It may have slipped.
 
I was talking to my machinist the other day and I told him about my lunati cam I just got he said make sure that you degree it. He said he was building a Chevy motor and when he degreed it that it was way off and so he checked the lift and it was way off. So he pulled the cam out and lunati had sent him the wrong cam! Lol he was building a race engine and they sent him a street cam. Of course lunati fixed it and sent him the correct one no question asked but you may want to look and the end and make sure it is exactly what you think it is.
 
I did check cam number and it is correct, as is the line lift, I did send timing chain back and summit sent another one with the same results,
 
It would lead me to believe that the retard is indexed by the crank keyway at this point. What year model of 429 crank is it? If that’s the case, the simplest and easiest way to correct it would be to have a new keyway cut into the crank sprocket.
 
are the dots at 6 and 12 o,clock? if so, you are on #1 tdc in a ford. you don't set them at 12 and 12 like mopar for tdc.
 
Yup 6/12 dot to dot T.D.C., motor is original 1968 429, internal balanced. Billet 9 key roller chain,

I trust my work on the degreeing it was just a head scratcher it was that far off, I reterted the crank gear and got the cam in at 105. I guess like what was said earlier... tolerances stack up
 
The worst one I’ve had was 8 degrees off. Swapped timing sets and we were 2 degrees off, so a 6 degree variance between them. We also discovered a .005 dip after the lash ramp on a cam. It got sent back for replacement. Always check both intake and exhaust lobes.
 
So you determined TDC with dial indicator? Not sure that is accurate enough. There is a bunch of degrees of dwell at TDC. Degree wheel and piston stop. Unless you used degree wheel and a set distance down in the hole to do it.
 
If you’re sure tdc on the wheel is really tdc....... and you’re comfortable you did the lobe measurements correctly...... it is what it is.
That’s why you buy the 9 keyway timing set...... so it's easy to move the cam.

FWIW, I use the dial indicator to determine tdc as well.
Usually .200 or .300 from tdc, equal degrees on either side of the pointer.

I’d have double checked everything once after I came up with those results the first time.
If it repeated...... I’d have called it good and buttoned it up.

I really couldn’t care less what dot lines up with the other dot....... as long as I know where the cam is(and it’s where it should be)...... that’s all I care about.
 
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