timfoster405

Just installed e-force on stock GT making 475 rwhp on auto at 11.50 psi... thinking of getting JBA's Shorty's and Magnaflow catted x-pipe...

Can't do long tubes...MD may be changing to CA emissions and don't want the hassle of having to switch back... or some State trooper crawling under my car because my car "sounded" too loud... I really want to stay emission legal for the exhaust (but not for the tune or the e-force tuner kit)

What can I hope to see going from stock manifolds and h-pipe?

I have searched the forums and most say the shorty's are NOT worth it, go LT...but that was for N/A.

Really would like before and after rwhp gains for a blower car.

thanks

onederful100

IMO shortys are good if you are 350rwhp, but over that you want LT's to get the most out of the higher hp. but if you are concerned about emissions laws, then shortys will have to be your choice. where i live we also have CA laws, but no way to enforce them so we all go LT's and o/r midpipes, and mufflers are optional. the LT's will make the blower/engine more efficient also, by lowering boost and increasing hp at the same time. for example i have a 10psi pulley but only see 8psi of boost and getting 450 rwhp with a conservative street tune, also have a race tune that is untested.

timfoster405

No mufflers?... I have to go to the state run emission station every two years and a state employee looks under the car with a mirror for cats... granted... right now if he sees a LT cat, he/she will really not know that it is not in the right place...but I can see a day where they are going to crack down on this...

Z06 Killer

I too am curious about gains from shorties on a F/I car. I live in California and I pride myself on the fact that my car is a very low 11 second car and is 99% street legal here in my town... (the 1% would be my tinted front windows)

stealth_GT

I think you will gain greater throttle response, but not so much HP.. pretty much maxed out on that department (475, stock motor/tranny) I would say..

mygt500

It will change the flow rate out of the motor and remove heat faster so yes you will have a gain but not much. At WOT it will be a beast!

tonkpils555666sas

Im from MD... come to Frederick to have your car emissions tested... they dont check under my car with mirrors... they just check for check engine lights... and I have no cats. and I dont think MD is changing to CA standards...

even then, its possible to get around by having your car sound quiet at an idle or cruise, but loud as hell at WOT... (and not get pulled over)

you could always replace your cats with resonators...

Jersey Stang

if MD is PLANNING on changing emission standards....doesn't that mean you've grandfathered the law? They can't expect all drivers to change their exhaust setup on previously modded cars.

mustangtestuser

He's not grandfathered in. It's already a federal crime to remove a working catalytic converter and has been for a long time. I think the 1990 Clean Air Act imposes a $2,500 fine for tampering with factory emissions equipment. You'll have to check, but I think removing the factory cats and replacing them with a high flow cat is still technically illegal.

All a state has to do is start checking. The law is already in place.

BFMacias

If emission standards pass to CA regs in MD I swear to all mighty DIOS you will have to change your set up. Getting "grandfathered in" makes absolutely no sense with the Demo's in office. Realize where this country is going toward emissions standards. Dont hope for a second that things are going to get better. Mark my words.