gtdoggie

Love,love love my 4.0 RS! But, am considering pursuing a more biting exhaust note with an aftermarket exhaust. Don't track(I apologize), but go out on spirited early morning drives through the canyons. Wouldn't mind gaining more power(who wouldn't). Definitely don't want to lose any. Wouldn't mind losing some weight(who wouldn't). Would like to be able to engage or disengage it at push of a button. Care about great quality of sound and don't want annoyingly loud drone at idle. Should I do it?, best choice of exhaust for my interest? Heard Akrapovic is the "gold standard". Is it worth it, or are there less expensive options that are as good or better. Would appreciate guidance please.

Arctic Wolf

Sharkwerks center bypass

senna

If I were you I would buy the M&M from Eddie. There is also an Akrapovic for sale here still. I have Akrapovic and like it very much, but the M&M is just as nice in SS.

tcsracing1

All you will ever need is a Sharkwerks bi-pass.

It is one of the best sounding too....

FYI: it is the center muffler delete but retains stock tips. (they also sell larger tips!)

Sport button still functions. Best of both worlds and lighter then stock.

gtdoggie

Does the SW center delete gain any power or weight savings?

tcsracing1

shaves off about 14 pounds.
no real hp gain, but it sounds like it!

tasman

Sharkwerks.

Serge944

I'm personally not a fan of the center bypass exhausts, so I would recommend the 997 Cup muffler. It's a high quality Porsche motorsport part, saves 45 lbs, and sounds excellent. It costs 1900 at carnewal.

RPW sells a similar style German made exhaust too, but I have no personal experience. Worth exploring.

Finally, you can unplug a connector in your engine bay so that the valves are always open. It gives you a nice sound below 3k rpm, and makes sure you hear every downshift, regardless of rpm and load. This is what I'm going back to after I remove my center bypass.

85Gold

Eddie at race parts warehouse with the M&M side muffler delete is the way to go. Sounds good and doesn't kill your hearing or your neighbors. Drops around 45# and adds around 20whp there is a thread about his same day dyno test on TrakCars 4.0.

Peter

Izzone

Akrapovic.....it's a 4.0 they deserve it

Zero drone

NJ-GT

RPW Eddie and M&M, we witnessed this muffler making a ton of extra power in both the 3.8RS and 4.0RS.

Eddie - RPW

Tks for the referral guys.

OP, if you're looking for power improvement, weight savings, and massive heat source out from the back of you're car, I believe I can help you.
We did extensive tests and found out the ideal set up and diameter for the 4.0 a lot of the new Grand Am cars are currently using our headers with straight exhaust also. It's proven to make power, same day, same dyno.
Sounds really good in my opinion without drone.

Here are the facts:

Trakcar GT3 RS 4.0, stock vs RPW side muffler delete by M&M.


Stock:


Stock system removed:


RPW in:




This is also another GT3 RS 4.0 that uses the same system:



Video:

Please let me know if I can help.

Eddie.

TRAKCAR

Just sound = Sharky and you keep sport button.
Money no object full Akropovic but you lose quiet/load button but gain some power and lose weight.

I chose M&M for super nice sound, side muffler delete M&M from Eddie
Also no sport button anymore but at low rpm it's quiet and high rpm it screams so if I want quiet I keep under 4000 rpm.

It made 18HP more we swapped exhaust on the Dyno. Looks very high quality in SS (See above) but they also have a Ti one that I'm talking to Eddie about for extra 10lb savings.

Eddie - RPW

Thanks for the input Peter,
He said it all, but Akrapovic doesn't make the same power. Akrapovic is a one size fits all system for 3.6 to 4.0 cars, which have completely different needs when it comes to exhaust flow.
Extremely good quality nonetheless.

Red Bear

Since I drive mine on the street/ track... wanted the power gain and keep the function of the sport button duel tone OEM mufflers...GMG headers and rear section center bypass was my ticket.