Dual-mode muffler with variable back-pressure system

is standard. Is this required? I think it's just to help with emissions and gas mileage .... we need to open that up

 

it's supposedly supposed to give you better low end power and torque, then open up when turbo is spooling to allow max exhaust.

 

Damn, you beat me to it. Depending upon how you mod the car and how you want it to drive it doesn't sound necessary by any means, but it may be beneficial for general driving and accelleration.

 

Turbo cars usually mean more exhause more power. I think it is to lower the noise of the car at low or cruiseing speeds.

 

in theory it would but from the picture I saw it looked like it was just a spring loaded device.

unlike the ferrari system which is actually connected and operated by the ECU


the literature I read said it was to lower the noise level not for power gains.

 

we have this on 3s cars like vr4 and stealth TT. it has a sport mode and tour mode. the tour mode has obvious power restraints but it opens as you open the throttle high enough. the sport mode is louder and more powerful. i liked it but i dont need it. it does make the car a good sleeper for cops though, when they ask whats on this car?>>> "nothing oficer, listen.
i kept the stock cat back on the entire time i had the car. i still ran mid 12's with an aftermarket downpipe and the stock cat-back. the quieter mode was also nice when having mom or a girl in the car.

 

I'm curious - How do you change modes?

 

in the earlier vr4 there was a switch. in the later models they got rid of the switch.

 

yeah, theres a button to the right of the steering wheel which changes it up... its most likely going to be the same mechanical thing on the evo. i use the tour mode very sparcely. always on sport.