I have a 502 gen VI short block with Srp flat top pistons(believe stock from GM)
That I am going to be building with 315 AFR heads and the crane 741 cam.

I believe the compression ratio will be 8.9-1 What is an estimate HP & torque this engine will put out?

Is the compression to low? Should I be boring the block .030 with more compression? or is that not needed?

8.9-1 sounds great for reliability purposes but want to make sure it will still put out enough power.

Thanks!

If it were me 9.5-9.8:1 and a cam that wasn't designed for crap heads 20 years ago

Just get the 315 heads with smaller chambers to get the compression up a bit. Then go with a custom cam, with more lift, to take advantage of the 315's cnc flow capability.

i would go with 10-1 and a cam from bob madera,he also can get you a fair deal on the afr heads.650 hp is what i would predict.edit in,i just reread your post,imo the 305 would be a better choice for your application.

answers in red

and yet it still works today.

EFI or carb ?

Yeah it works, but the profile is way off for those heads. Why pay $450 for that when you can get something better for the same $$?

Yup what he said ^^^ and a new dist. gear lol, custom grind is the way to go with those heads, Id bet it would make another 40 hp

depends on what exhaust you are running,but lets say cmi elbow tops around 600,gil or stainless marine 580-590 that is what i am seeing on a fully dressed marine engine on my dyno,add a little more compression and play with some cams 30-50 more hp,just depends on were you want your power curve to be,the afr heads flow real well and don't need a lot of cam to make good power