Dumb questions #178, 179, 180 I've asked this year...

If it were mine this is what i would do. I'd first degree the cam and see what your working with check your lift centerline and degree opening at .050. IF the head and everything is still on id do a cranking pressure check if your cranking pressure is low id pull the heads and start checking further. Id measure the piston height if its stock pistons and a stock block its probably somewhere around .08 in the hole then id cc the j heads and calculate the compression using the .050 headgaskets. More than likely you will be in the mid 8s if you have one cylinder that has an extreme difference im cranking pressure i would check the valves to make sure they are not leaking and are seated if all is well id dig a little deeper and check the rings. You will get more compression out of the 302s but the j heads will flow better. Depending on the cam id make my decision compression vs flow. If it's a small stock cam id port the crap out of the 302s and maybe even have them milled to bring my compression up some. A large cam with low compression is gonna be a dog on the bottom end. So at that point id probably pull the cam and start over. Your cam is gonna dictate your springs and valve clearance your not gonna be able to run a 508 lift cam with stock 302 heads. You will have to cut the guides replace springs etc. If it turns out the block has been decked and you have after market pistons and probably run the j heads and try to get the compression into the 9s with a mild cam 450-490 lift and 260-270 duration. That would be a fun 318