I Know this ahs been asked before, but what should I expect out of my stock '85 460 with emission heads and chain set? It has a 600 vac. 2nd holley and factory intake and exhaust manifolds. I will be running dual 2 1/2 with flowmasters and side exit behind the tires. Also what will I gain by putting that older (pre-emissions) chain set in it? how far back do I have to go to get the older set?

 

Maybe you can get moved to the 385 forums.

460s of that era were about 230hp, 390tq. + your mods, - age and wear, you are somewhere near that. Change the timing set, maybe 15 or 20 hp...WAG.

Pre-71 methinks for the timing set, but you can search the 385 threads or, if you post gets moved there, get an answer. Monsterbaby is an excellent resource for these engines.