Gt40p Comp Springs, 510cam, Question

TRIBUNAL said:

So I had my GT-40p heads rebuilt and I told them my cam is:
Lunati Street/Strip Camshafts 20350514
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.510 in.

Valve Lift with Factory Rocker Arm Ratio: 0.500 int./0.510 exh.
So they rebuilt the heads and put in new springs.
The guy I told the cam info to, told the guy that rebuilt the heads, the cam was about 500 lift.
The guy I spoke to said they're fine and the person who did the heads, who is also the owner, said its possible I might be making contact with the seals...
Needless to say after spending $590 on a basic rebuild I am pretty agitated if I now need to change the cam or maybe change the springs.
They used these springs: Comp 942-16
Outside Diameter of Outer Spring (in): 1.437 in.
Coil Bind Height (in): 1.125 in.
Damper Spring Included: Yes
Spring Rate (lbs/in): 339 lbs./in.
Inside Diameter of Outer Spring (in): 1.039 in.

Am I good with these, or do I need to consider another option?
Thanks in advance for any help

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You need to call the cam mfg and use what they recommend IF they say what you have won't work. But it's a good practice to buy the springs with the cam so you know you're getting the right parts. If the cam is used, then call the mfg.

So we're talking a difference of .010. That's ten thousandths of an inch. Grab a feeler gauge and look at .010. It aint much.

If you were that close when reporting the lift at .500, I think they should have said something. If you want to be sure, you need to measure the clearance. You'll need to remove at least two valve springs. One from an intake and one from an exhaust. Without the spring installed, put the retainer and keepers together on the valve, hold the valve tight against the seat and use caliper gauge to measure the clearance between the top of the seal and the bottom of the retainer. If you have the tools its easy to do. With a .510 lift, you'll want to find a measurement of at least .600. This would give you the required minimum clearance of .090.

If you dont have the tools, take the heads back and ask them to measure it for you. A machine shop should be able to do this in just a few minutes.

Actually, check with the cam manufacturer to see what they recommend as minimum clearance. And, is that clearance to the top of the valve guide or to the top of the seal when it's pushed down over the guide. My previous post I said .090 but I'm not sure if that is with seal installed or not.

John Dirks Jr said:

Actually, check with the cam manufacturer to see what they recommend as minimum clearance. And, is that clearance to the top of the valve guide or to the top of the seal when it's pushed down over the guide. My previous post I said .090 but I'm not sure if that is with seal installed or not.

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I'd be less concerned with the lift/bind and more concerned with the open and closed pressures at this point. Valve float is baaaad.