I have a new 350/290 hp/326 tq chevy crate engine with 76cc heads. I also have a set of 416 heads to be rebuilt with 1.94 X 1.50 valves. This engine is to be set up for torque mainly, Going from the 76cc heads to the 58cc heads would increase my comp about how much? And would the 1.84 valves be better for torque?

 

Go with the larger 1.94" valves. Typically you will lose a few cc's out of the chamber because the chamber wall near the intake valve edge has to be clearanced a little to clear the larger valve. You'll end up with about 62cc.

Depending on the factory gasket your cr is 7.98 to 8.35:1 now. Assuming 62ccheads and again depending on the gasket used your cr will be 9.06 to 9.60:1
-13cc piston dish volume .025" deck clearance
if the heads was milled to restore 58cc your cr would be 9.44 to 10.02:1

plan on a 62cc finished chamber and use a .015" thick shim type gasket your cr will be just right for a torkie motor
9.6:1 Change the cam.

 

torquey eh?
Is this planned to go into your '84 camaro, or...?

Yea, 1.84 valves won't improve torque in your case, although that line of thinking works for other things in that vicinity. I think you'll be happy with that combo.