Mach 1 aluminum blocks, how much horsepower can they hold with forged internals? Should I look into a different block to go above 500 horsepower? Car has 108,000 miles, 5 speed. Id like to get high 500's with a Vortech without any issues. Where could I find an upgraded block for the 4.6 4v if so.

Thanks!

 

Looking for an assembled short block or just a block ?