The other part of it is you can find a ton of parts for big block. My 471 I bought a new set of eagle rods and a crank that was already offset turned for $800 and bought a set of dish pistons with sr heads. It had 125 pounds of cranking compression it would run on 87 octane. I had a 200 kit on it and it ran 5.70 at 124 on 13.50 et streets and exhaust 3400 lbs and drove it all over.