Cam installation

I'm installing a stock, resto cam in my 426. Intake CL is supposed to be 112. I've checked it multiple times and mine is measuring at 106. I found TDC 2 different ways... with a stop and using the dial indicator. Both were right on. How can it be that far off? What factor would create this 6 degree difference from advertised?

The crank I have was a Swap meet find. It was used but was still very nice and is still std/std. There was something very unusual about it that I didn't notice until I went to install the balancer. The portion of the snout that accepts the balancer is machined further into the crank than normal and has a 2nd key-



I had a spacer made from a timing chain sprocket to fill the space-



I posted this years ago when I first ran across the issue but no one had a solid answer. I can't help but think this mystery crank has something to do with my CL issues. Now for the really stupid questions... Are there cranks that have adv/ret built in? Am I using a Mopar crank meant for something else besides a street hemi?

Please help. I am NOT bolting this thing up again without everything right and without ANY uncertainty of what's going on.

You probably need to figure out who made the crank and ask them. Looks like it was probably designed as a blower crank and was machined different than stock. Very possible that whoever machined it got the key in the wrong place. Other option is that your cam has 6 degrees of advance machined in. Doesn't seem like a big deal to me, I'd run the cam at 106 anyway or maybe back it off a couple of degrees and run it at 108. Since you have some questions on stuff you might go ahead and double check the cam timing on #6 hole while you are at it. If #6 is the same as #1 then you should be good to go.

Having it off 6 degrees isn't terribly unusual. Either get a timing set that has multiple degrees on it, and some degree ecentrics and get it perfect.

It may have nothing to do with the crank, it can all be in the timing chain set, or the way the dowel was installed on the cam. Its really why we degree the cam in the first place.

I did a Chevy once that was so far off we had to slip the chain/timing mark one tooth, then put the biggest eccentric in the other direction to get it right.

I had a cam that the key way was off by 23*..
just for kicks I lined the dots up... the valves
crashed the piston... but I run that cam after I
degreed it(SB)
EDIT
When I bought the cam from the mopar dealer the
box had been opened and taped closed.. so I assume
the guy before me just tried to line up the dots on
the chain set and it crashed and he took it back

You might mockup the #1 rod/piston & get it at TDC & see if the crank snout keyway is at 1:30. other than that as said retard it 6 deg as needed. EDIT I'd see if both the sprocket dots are clocked the same in relation to tooth root position if you have another known good timing chain/gear set,same for the cam keyway or dowel pin (I ain't up on BB's) compared to another cam. all that is left is the clocking position of the lobes on the stick. moving (1) tooth is 15.6 deg on the crank (SB)

Thanks for the input. Guess I'm stressing over nothing. Got a higher end, billet, 9 keyway timing set. With this new set lined up on the the "0" marks the cam centerlined @ 108. Adjusted the sprockets and BOOM... right on the money, 112 as desired.

I would have left it advanced for a street motor.

I would bet that cam was meant to be installed at
106-108.. its a 112 LSA

Put the timing cover/timing indicator on with the damper and a degree wheel if the damper is not marked 360*. Reset the crank to #1 TDC using the degree wheel and check the damper/indicator. Check the damper to see if #1 TDC is correct on the timing tab (or close). This will tell you if the keyway is in a non-stock location and you can adjust cam timing and timing marks accordingly. Cam timing using a degree wheel set to #1 TDC will be accurate, regardless where the keyway is. Use the adjustment in the timing set to put the cam where you want it.

LSA? Found it... Lobe Separation Angle. The paperwork that came with the cam clearly says intake centerline is 112 DEG. OK, now I'm all stressed again.

He bets it's meant for a 106-108 INSTALLED centerline. Not lobe separation.

Correct... its a 112 LSA(lobe separation angle)
cam but in MOST cases they will say 106 or 108
installed degrees... its no big deal but the lower
installed degree will make more low end power...
for a street car I would want the low end power since
you dont tend to rev to high.... but this is just my
opinion

if that cam is ground on a 112 lobe seperation angle and you can install it with the intake lobe center at 106 to 108 I would do that The reason being advancing the ILC makes the motor have more bottom end(low rpm power under 5000 RPM) Once you get the intake lobe center were you want it(108) take the time to check the exhaust lobe center to make sure it is ground on a 112 LSA also If it is ground on 112 and you have the intake lobe center in at 108 ATDC the exhaust lobe should be advanced the exact same amount, it should be 116 BTDC One degree either way is not worth worying about, if it is more than that then send it back and try another one

I agree as it sounds like the LSA would be 112. On my cam it has a 110 LSA and they say install it on a 106 installed centerline. Mine came out at 105.5 and I left it there. Ron

I will be installing at 108. Thanks for all the input. It got me researching and confirming. Moparts (you guys) has yet to let me down.