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Gt-one 5.1 Exhaust

I also own a 5.1...love[d] the sound, but now it's developed a rattle from one of the cans. Does anyone know of place that can repack an exhaust for a FI car?

Many thanks, and sorry to dig up and old thread:redface:
 
Re: Gt-one 5.1 Exhaust ... FI cars beware!!!

I also own a 5.1...love[d] the sound, but now it's developed a rattle from one of the cans. Does anyone know of place that can repack an exhaust for a FI car?

Many thanks, and sorry to dig up and old thread:redface:


I no longer have my NSX. :-( And do I miss it and that 5.1 sound very much.

However, in retrospect, I believe that the 5.1 exhaust should not be recommended for FI cars.

I have it on very good authority, that the 5.1 exhaust has too much back-pressure and could cause piston ring landing failure. That was the fate for my car. And I understand that was also the fate of a few other FI cars with 5.1 exhausts.

The 5.1 exhaust is designed to make great sound, not to make more HP. This was very evident when I originally did dyno tests between 5.1, CT, Taitec GT and a custom exhaust. The 5.1 exhaust made 6-8 WHP less than the worst of the rest.

If you are currently running FI with a 5.1 exhaust, I highly recommend that you get a compression and leak-down test - immediately!!!

The problem with the 5.1 exhaust is its sound. It's addictive!!! I found it difficult not to do a few hard accelerations every time I drove my car.
 
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Thanks for the info, and sorry to hear the fate of your car.

I've had mine for about 75k hard miles; 20k of them being on high-boost. Autowave was surprised, because the exhaust has so much flow, they had to richen up my map more than usual under boost. If I can't find a place to repair it, then I'll likely start looking at the STMPO Messiah Exhaust.
 
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Do you guys really think this exhaust is that good sounding?

I have it on my NSX and always complained it's a bit too quiet and "tame" - whenever I'm out with the norcal NSX guys, I can't even hear my exhaust!!!
 
Do you guys really think this exhaust is that good sounding?

I have it on my NSX and always complained it's a bit too quiet and "tame" - whenever I'm out with the norcal NSX guys, I can't even hear my exhaust!!!

Really s4play? I can remember that you used to complain about how loud my exhaust was during a few NSX drives several years ago. :p :biggrin:

Anyway, I believe the 5.1 sounds loudest when using CT headers and CTSC. With stock headers and a non-FI car, it is a bit tamer.
 
Re: Gt-one 5.1 Exhaust ... FI cars beware!!!

I no longer have my NSX. :-( And do I miss it and that 5.1 sound very much.

However, in retrospect, I believe that the 5.1 exhaust should not be recommended for FI cars.

I have it on very good authority, that the 5.1 exhaust has too much back-pressure and could cause piston ring landing failure. That was the fate for my car. And I understand that was also the fate of a few other FI cars with 5.1 exhausts.

The 5.1 exhaust is designed to make great sound, not to make more HP. This was very evident when I originally did dyno tests between 5.1, CT, Taitec GT and a custom exhaust. The 5.1 exhaust made 6-8 WHP less than the worst of the rest.

If you are currently running FI with a 5.1 exhaust, I highly recommend that you get a compression and leak-down test - immediately!!!

The problem with the 5.1 exhaust is its sound. It's addictive!!! I found it difficult not to do a few hard accelerations every time I drove my car.


The design of this exhaust seems counter-productive to an optimal FI application. However, wasn't it reported in another thread that it was indeed tested and the flow was adequate?
 
I don't recall such a statement! I just prefer the single tips over the dual tips that's all.

Since no one makes a HFC/Testpipe for the 2002+ cars I've decided to instead shop for a nice quality header....

Fujitsubo comes to mind but so rare and hard to find, does Comptech header design flow better than stock?

Definitely need more throatiness in my NSX as it's more tame sounding than my IS-F!


rick
 
Re: Gt-one 5.1 Exhaust ... FI cars beware!!!

The design of this exhaust seems counter-productive to an optimal FI application. However, wasn't it reported in another thread that it was indeed tested and the flow was adequate?

I'd like to find that link...I do know that with the 5.1, Cantrell AIS & Cantrell headers, I was running lean. AutoWave said I had a lot more air flow than they normally see from a CTSC setup.
 
Re: Gt-one 5.1 Exhaust ... FI cars beware!!!

I'd like to find that link...I do know that with the 5.1, Cantrell AIS & Cantrell headers, I was running lean. AutoWave said I had a lot more air flow than they normally see from a CTSC setup.

I have a pride V2 and haven't seen any issues. When I talked to shad he said a potential problem might be you will see more boost with a restrictive exhaust, but I have never seen more then 6lbs.

I would like to test a Comptech Exhaust to see if it dyno's more.
 
who's car is loud enough to drown you out??? :biggrin:

Quite a few guys have louder cars but I hate being behind you the most!

P.S. I dropped by south bay Honda yesterday but they said you moved to Pleasanton!
 
More of ten than not the exhaust sounds better when ur in the car than when ur right behind it.

Being outside of the NSX and most exhaust sound rice and unrefined.

Supercharge any car and the exhaust note is much more aggressive sounding from the additional dynamic pressures.....
 
More of ten than not the exhaust sounds better when ur in the car than when ur right behind it.

Being outside of the NSX and most exhaust sound rice and unrefined.

Supercharge any car and the exhaust note is much more aggressive sounding from the additional dynamic pressures.....

This exhaust sounds very tinny, when it's cold. After the exhaust warms up though; it's a keeper!
 
The 5.1 is no more restrictive than a stock exhaust. You don't see comptech warning people not to run it with a stock exhaust. They say you will get more power with a comptech one, but it won't cause engine failure.
 
The 5.1 is no more restrictive than a stock exhaust. You don't see comptech warning people not to run it with a stock exhaust. They say you will get more power with a comptech one, but it won't cause engine failure.

According to Shad at DA he tested my NSX with the comptech exhaust and it did yield more power. I think it was between 5-10HP when compared to my x pipe that I did with the stock sized exhaust tubing that I used from the OEM muffler.

It's the high boost setup that gets people in trouble with restrictive exhausts....
 
According to Shad at DA he tested my NSX with the comptech exhaust and it did yield more power. I think it was between 5-10HP when compared to my x pipe that I did with the stock sized exhaust tubing that I used from the OEM muffler.

It's the high boost setup that gets people in trouble with restrictive exhausts....

So, what is a recommended replacement for a high boost setup; the STMPO Messiah? I'd like to keep my F1 sound...
 
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