How much horsepower does a 572 put out?
620 or 720...better read up on it/them >http://www.chevrolet.com/performance/crate-engines.html
If you have the funds put an LS3 in your "68" it will be lighter,handle better and make as much power as a big block. That's what I did with my "68" Camaro, it had a big block but I went with the LS3 and now i'm hooked, over the winter i swapped out the cam and some port work and i'm just over 600 horse (the pic is from last year before the cam swap)
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