452 heads cc's

And you know, IMO, people make WAY more hooplah over hardened seats than they're worth. On most applications like we do, they simply are not needed. People will argue that till the end of time, but it's true. With these street cars, they are pretty light, especially A bodies. Normally, they have lower gears than stock that help make the job easier on the engine to move the car. Anything that keeps exhaust temp down. Vehicle weight, gear ratio, big cooling systems that cool RIGHT. All that. Now on a truck, especially a tow vehicle, or one that's used to haul stuff, you'll want hardened seats. But by and large, on our cars, it's just a myth that won't go away. Just because all the forums and magazines say it, doesn't make it true.
Stainless valves also will help if the seats aren't hardened.