fitment issues with GruppeM exhaust?

[Scrubs]

I'm writing to ask if anyone with the GruppeM exhaust (version 3) has had problems with fitment? I have a 1991 NSX with Comptech headers. I received it 3 months ago. The exhaust consists of two main parts. A Y pipe that attaches to the headers and then a muffler assembly that attaches to the Y pipe.

If the pipe is attached to the front cylinder bank the rear cylinder bank is more than an inch and a half from fitting. Even if both cylinder banks are completely loose, it's impossible to line up the Y pipe and even line up all 6 bolts.

ScienceofSpeed has been helpful by pulling another exhaust from the same batch in stock and fit testing on one of their cars and ran into the same problem.

We've been back and forth with GruppeM's representative in the USA (AV Motorsports) and GruppeM in Japan. GruppeM blamed the headers on the car with out any explanation why the Taitec and stock exhausts fit fine. So, I went through the trouble of installing my stock headers. With the stock headers in place, I can install the front bank and then flex the Y pipe over to the rear bank. However, this causes the two factory header flex pipes to stretch at such an extreme angle that if you try to install the muffler portion, the tips don't even fit into the rear valence. There's no way this thing is fitting properly.

ScienceofSpeed sent the photos to GruppeM and the response is that they checked fitment in Japan and didn't have any problems. Obviously there's a problem here and I can't believe I'm the only one to find a problem with this $2700 exhaust.

Does anyone have any help or feedback they can share with their GruppeM exhausts? I'm ready to have this exhaust modified to fit properly, however, it seems like a real shame to have to cut up such an expensive exhaust - you'd think that fitment would be perfect out of the box.

 

[CDub]

I have DC Sports headers and I noticed that when I had the GM v3, it was harder to align the y-pipe to fit. But I managed to do that. The GM v2 that I have now fits better.

Either way, these GM exhausts never line up properly and have a tendency to shift to the left with CT, Taitec and DC headers.

 

[1946vw]

I bought one from SOS and had to cut and weld the Y pipe for a better fit.

 

[nsxinkl]

I have problem with my Gruppe M v3 exhaust too. The exhaust tips couldn't align properly after the installation. I had to modify the connecting pipes of my SOS headers to align the tips of the exhaust.

 

[joboo]

I bought my 91 NSX with GM V3 and stock headers and it fits fine but the pass side exhaust hanger did break off and I still need to get that welded back on. But this is good to know because I will get headers and would like to see how you guys resolve this problem. I will be going with Cantrell headers.

 

[joboo]

any updates on this problem?

 

[drewdeezee]

I bought one from SOS and had to cut and weld the Y pipe for a better fit.

I too had to have the Y-pipe on my v2 sliced and rewelded to get the exhaust to not burn the rear valance. My situation was a little bit different because I got mine at a great price, but I do agree -- it's a damn shame to have to do that after forking $2700 for an exhaust.

On the other hand, once you have the exhaust installed, you will be intoxicated by the music the GruppeMs sing. :biggrin:

 

[SilverOne]

Same with my v3, just something I live with. I rarely look down or behind my car, so don't bother me as much.

 

[ffffanman]

What a Joke!
Just my 2 cents.
A company that doesn't stand behind its product.
What a disgrace.
Trev
I got my Top Speed headers for 550.00 with free air freight.
I will never complain if the flex joint breaks.
But 2700.00 for a piece of tin that i can make and copy for around 400.00 and it wont fit and the company says its your fault. Give me a break.
I could be talking out of my A$$, but dont think so.
Come on GruppeM

 

[drewdeezee]

I'll post an update to this thread after I attempt to install aftermarket headers and include as many pics as possible.

I have to admit that I'm a GruppeM exhaust fanatic and I'm willing to overlook the fitment issues, droning, and remove/replace every other year for smog tests. Why do I love GruppeM? The sounds, followed by the looks, and maybe the fact that it's a love or hate exhaust. It's a passion and almost an obsession because I would do it all again if I were to start from scratch (even after reading all the negatives posted in this thread).

Shawn Sejera said it best in NSX Driver 2005 Issue 3
Article titled The Case for Murder :

Do not let these obstacles hinder your resolve because the end result is a destination that yields greater satisfaction than the journey.

To answer Scrub's question about modifying the Y-pipe, I recommend to go ahead and make the leap. If you're still not satisfied with the exhaust after installing it to fit, you'd still be able to sell it easily. (Maybe to me. :smile: I've been wanting to write up a GruppeM version 2 vs version 3 thread for a long time now) :biggrin: