For me it helped, well of course i changed several things at once so its hard to say exactly how much it helped. I switched from a hyd comp 565 cam to a 572/579 solid in my 440 with indy heads (stk ports though) and a demon 850. with auto trans and 3500 stall. I gained a good bit. I was 7.90's and now i run 7.20's (in 1/8th). I like it!