Im building a 496 and cant really afford aluminum heads. I have a good set of 840 casting number rectangle port heads. They need a valve job, probly milled and i would like to put in hard seats and stainless valves. In the mean time i was given another set of rectangle port heads that have brand new stainless valves and have been ported and polished about 30 years ago. One heads was damaged and i do not want to use them. I pulled the vaklve to put in the first set of heads but found out the intake valves are 2.30 intake and stock 1.88 exhaust. I want to make as close to 600 hp and close to 600 ft lbs of torque so the question is should i have th larger intake valves put in the heads? Would there be a significant gain by going to the larger intake valves? Or just buy new 2.19 valves