This may sound stupid but.....

Anybody know what kind of power (if any) a 305 would make if I used 350 041 heads,Isky cam with .390 .410 lift, 276 int 280 exh duration,bowtie cast iron intake and a quadra jet (professionally built).All this for dirt track on 1/2 mile.The 350 bottom end crapped out and can't afford to build one right now,trying to make it til the end of the season.I could use some 882 heads that are angle cut,trying to stay within the rules.Any opinions will be appreciated.

Thats one of them things that you can't tell till you bolt it together. :rofl:
Good luck

The 350 heads will lower your compression, but the camp will help with the power a little bit. The heads from the 350 will blow better though I would imagine. If you can find out what year and car the 305 came from, I can get a close approximation of what you'd be looking at for power out of it.
Jake