pick up a chevy hi performance mag. In the back there are some deals on SBC heads. I myself received some 350 heads for free and was going to rebuild them. But then I found out that rebuilding them to be nice flowing heads would costed as much as a brand new set of heads! Check out the Vortec heads, there about $500 for a pair. the only thing is you have to get a intake that supports the vortec design. And also, in the CHP mag, there are some for as low as $350 a pair, but I don't know anything about the company. Good luck!