Hey new here, have a 1974 valiant with 1972 413 RV engine, previous owner had cobbled on some 440 headers. They are all different lengths with no collectors. I have read that maybe some 516 heads would help low compression pistons and allow me to maybe find some exhaust manifolds that would work.The engine has a regular water pump now. stock intake with 4 barrel Holley. If these heads could work, may change to mild cam and an aluminum intake. Just like to have a nice driver. What do you think,Thanks

 

The closed chamber 516 heads were stock on 413s. You must change pistons to gain compression. Custom pistons may be the best rout for you, I don't believe pistons are offered any longer. If your willing to change the rods to a .990 pin you might find a chevy piston that works..

 

thanks, like your car