I see in all the dyno's the rwhp increases but haven't been able to find in a thread(i'm sure it's there...sorry) what that equates to in ENGINE hp. I just did my first mod., char. filter removal and RPI scoops, filters on backorder(Eloy is a great guy to work with). Both were very straightforward to complete. Only part that was a little difficult was releasing the pin on the inside of the grills. Big hands I guess. Anyway, a friend of mine asked me how much ENGINE hp does it add. From 507hp to ????. Is the percentage increase the same as the dyno rwhp? The other question is has anyone run against a bone stock from 50mph-whatever speed to see what the scoops, filter removal does on the street. Thanks guys for all the input and instructions/hints. Next project is the cd changer out, Ipod in conversion.