Building a new motor with a stock LT4 cam. I have all the specs for the cam except the intake centerline. I need this spec to degree my cam. Does anybody actually know this spec.

Thanks

 

Probably 114 or later, but better to have it be about 3-4 degrees less than whatever the LSA is. If you don't have that, then just find the current ICL, and the current ECL, then add those together, then divide by 2. That'll give your LSA. If it's 115, for example, then I'd suggest an ICL of 111, for example.

 

I can't go on guesses. I need to know what the actual numbers are.

 

Why the hell does it have to be as late as GM puts it? What do you gain by giving up low-end and mid-range?
You can know what your LSA is by checking both CLs.
From there, why go with GM's retarded retarding, when ALL aftermarket cams come with 4 or 5 degrees of advance ground in? Average power improves. And that's the goal, right?
This is why most good timing sets come with multiple positions, so you can put the cam where you want it, to hell with production compromises. It's not like any modern cam ever arrives 4 degrees off spec. 1/2 degree, sure. 1 degree, maybe, if it's a cheap cam.
Furthermore, 1 degree of difference isn't gonna make much difference. You're nowhere rear having clearance problems between the pistons and the valves.
1 degree is worth maybe 100 rpm, but the intake closing is already way late in relation to the intake duration. Typical GM. They give you a closing of 38 degrees with a duration of 204 degrees. Any mild performance cam with that late of an intake closing is going to be near 220 degrees. Just like the GMPP "HOT" cam.
Finally, if the spec didn't arrive with your cam, then noone else is going to know it, either.