need more power..

ok i have a stock 86 5.0 and its got 30,000 mi. on it. i was wonding if i put gt40 heads on it from a expolorer and the intake manifold on there and some sork of cam, roller rockers and all that ****. would i be close to getting 300 horse and i am putting 3.73s in it this winter i know i need mass air but what do you guys think it will do what year did the heads not need the special headers. and does anyone know about the piston to valve clearence.. thanks
 
I am gonna run an explorer intake, ported e7 heads, and e-cam, etc. I have been told i will be in the 260-280 hp range. It's similar to your combo.
hope that helps.
:D Also if you run ported stockers, you wont need special headers.
:nice: