That is true. Best thing you can do is dyno your car before and then again after and see what the differences are. (Ideally on the same day in the same conditions) A lot of these companies should have rolling road facilities available to them, with most companies offering you a full money back and return to stock guaranty if you are not happy. Its the only way you can be curtain. Even when they offer your their own before and after findings, whose to say they are true.
.: R56 Cooper S : Dyno'd 192bhp :. .: H&R Springs : JCW Discs : Forge BOV : Alta CAI :. |