anybody out there change there stock 500 hp manifolds to a performance manifold with any good results if so what make and what kind of results. thanks 32 thunder rick

I went from the stock Merc/Gils to CMI's on my 525SC. I saw no difference in performance.

Just last month, on the dyno, with a HP500 with AFR heads and a Crane 741 cam, I saw a difference of 25-30 horsepower gain with CMI elbow tops vs. the stock Gil performance manifolds and tails. Also a gain of 35 ftlbs of torque across the board.

Dave