I have a 99 m6 formula, full bolt on,tsp 224r cam, i put down 382 and 373 on a mustang dyno, headers i could feel a bit of difference, cam was a world of difference, what can i expect out of my new heads, prc stage 2.5 5.3 heads with cosmetic gaskets and true duals dumped at the axle. Also im hoping sound will improve with the true duals and eliminating my raspy loudmouth 1 setupim going with the moroso spiral mufflers, any opinions will be grreatly appreciated

 

425-445rwhp and 400-410rwtq is my guess..

 

that sounds very good... is that what they normally dyno?

 

bump bump

 

420-450whp sounds about right...might be a tad on the lower side if you going to dyno on a mustang dyno again.