stock 302 rebuild

well if you plan on doing any type of cam/heads you will need to put new pistons in it so why not just go ahead and do a 306!

Unless the new hardware requires the short block internals to be changed or if there are signs of major wear caused by abuse, I wouldn't open the motor up until at least 200,000 miles.

My '91 302 motor is still on the stock short block and it is well passed 300,000 miles on it. It currently puts down 400/530 to the wheels on the juice and has seen at least 180 pounds of nitrous through it. It still barely smokes at all when I get into the throttle.

I don't recommend abusing a motor to the extreme that I have. My point is that these motors can take a lot before they are "spent."

Does 86 not have notched pistons?