rbl

While aftermarket vendors claim a gain of several HP from simple bolt-on products (cat-backs, DVs, air intake, downpipes etc), why don't auto manufacturers simply include them into production in order to boast a more superior car? I can't believe it'd be that much more expensive to incorporate known technology into the production line. It's not like the aftermarket vendors have unearthed new automotive secrets that auto companies couldn't figure out.

Then again, it wouldn't be as much fun to have nothing left to mod anymore.

SeaTTleSlew

Emissions, fuel econ., engine life, cost (profit); not necessarily in that order!

RobbyTT

it should give you back what you're supposed to have...as far as boost, torque and hp.