Taitec GTLW muffler power gain

[L8apex32]

I just installed and dyno tested a Taitec GTLW muffler on my 1992 NSX with 143.3k miles. The only other engine performance enhancement are Top Speed headers. You can read about them on the Marketplace->Vendors forum if you wish.

My car had 242.65 rwhp stock.
It made 254.5 rwhp after the addition of the headers.
It now makes 260.2 rwhp with headers and Taitec GTLW muffler.

Based on a 12% power loss in the transmission and final drive, that is 295 crank hp at peak.

Torque peak was 187.35, 195.22 and 200.13, respectively.

Power and torque peaks do not tell the whole story. For example, although the header gave about 12hp peak improvement, it gave about 15hp improvement from about 6800 to 7300 rpm.

Similarly, although the GTLW muffler only gave 5.7hp peak improvement, it gave closer to 7hp improvement from 6800 to 7300 rpm. On the other hand, it gives somewhat less than 5.7hp after 7300 rpm.

In summary, you can safely say that, for this test case, Taitech GTLW muffler gives about 6hp improvement. This is around 2%.

I did not test with the silencers because I have not drilled holes in the tail pipes yet.

(I have the black and white print out with me [not scanned in] but expect to have the color print shortly. If anyone is still interested by the time I get the color graph, I'll post it.)

What else can be done with simple bolt-ons to improve NA engine performance?

 

[MvM]

Thank you very much for posting your numbers.
You have done all the basic big stuff.
Additionally, you might consider changing the ECU for a SOS or Dali-chip. There is not too much gain there but then again, it is also a very simply mod than can easily be reversed.
Another thing is the AIS air-intake and Uni-filter. Again, the gains are slight but again it is simple bolt-on stuff you can do yourself easily.

For your information, in completely stock form my NSX also had 242 RWHP.
How, with Taitec headers and Taitec GTLW exhaust, Dali chip, AIS intake, Unifilter and SOS big bore throlle body it makes 270 RWHP.

 

[Synthesis]

what does the butt dyno say? can you feel the extra 20some horses?

 

[L8apex32]

what does the butt dyno say? can you feel the extra 20some horses?

You can instantly feel headers. They improve the power even at lower rpms and that is noticable, even on the street. The same old foot/throttle position will push just a little harder and you can feel that.

On the track I can't say I felt the difference. Not because it wasn't there but because its hard to pay attention to changes like this when you are running at 10/10ths. Also, I am more focused on tire grip, the line, brake temperatures and brake effectiveness, corner workers, etc. The dyno shows it very much being there at the track.

For the muffler, you can tell its there because its loud. No way arond that with the GTLW. But, I can't feel it in my butt in street conditions. I've only had it on for about 1/2 a tank of fuel and I've been fretting over how loud it is more than trying to feel the power gain. Plus, now that we have the dyno numbers, we can see that it does very little for power below VTEC range, then it goes up to 5 ft-lbs until 7300 rpm. That you can feel.

I will say that two young mechanics who watched the dyno runs noticed the VTEC range. The GTLW makes my car make a louder sound when VTEC engages. If you've ever wanted to demonstrate VTEC to someone, this makes it easier for them to tell when it kicks in - both in sound and torque.

In total, yes, 20 hp is a significant difference and it would be hard to part with it now that I have it.

 

[Ponyboy]

Those are good numbers w/ the mods you've done. The only other bolt-ons would be on the intake side. I'd do the Unifilter or K&N air filter and an AIS. Don't know if you can get away w/ straight pipes in KS but I got a few peak hp out of using them.

The stock ECU is hard to beat.

Actually, you may want to put in some new plugs, get the fuel injectors cleaned and "blueprinted" (RC Engineering does this), and change out the fuel filter to make sure your present config is optimized.

Have you thought about getting your headers ceramic coated?

 

[L8apex32]

Re: the regular maintenance (fuel filter, plugs, etc,) I keep up with that stuff per recommendations, and a grain of salt. I may be due for plugs and a fuel filter. Maybe I'll do them the next time I adjust my valves.

As far as blueprint fuel injectors, are FI's cheap enough to buy new and send to RJ or perhaps just have them send me new ones? Or, will downtime be required?

Re: ceramic coating on headers, what is that supposed to do? I understand it helps move more heat out of the system which, by definition, improves performance. But, has this been dyno tested? What info is available on this?

 

[sojusoulja]

how loud is the GTLW? I was under the impression it is one of the quieter exhausts. I just sold my GT-ONE which was way LOUD!

in the market for an exhaust and am leaning towards the gtlw

 

[Ponyboy]

Re: the regular maintenance (fuel filter, plugs, etc,) I keep up with that stuff per recommendations, and a grain of salt. I may be due for plugs and a fuel filter. Maybe I'll do them the next time I adjust my valves.

Cool. I recommended it b/c maintenance schedules vary by owner and it's difficult to know where the owner is at w/o offending.

As far as blueprint fuel injectors, are FI's cheap enough to buy new and send to RJ or perhaps just have them send me new ones? Or, will downtime be required?

You can get new ones from RC - SoS carries them. Or you can get them cleaned and blueprinted - got mine done for $25 each. Or you can get some OE replacements for about $100 each.

Re: ceramic coating on headers, what is that supposed to do? I understand it helps move more heat out of the system which, by definition, improves performance. But, has this been dyno tested? What info is available on this?

Right. Increases exhaust gas velocity, smooths turbulance, better cylinder scavenging. I had mine done by Airborn Coatings in OKC. Don't have a before and after though. However, my M3 buddy got a 7hp increase from doing it.

Plus it looks purty.

 

[L8apex32]

how loud is the GTLW? I was under the impression it is one of the quieter exhausts. I just sold my GT-ONE which was way LOUD!

in the market for an exhaust and am leaning towards the gtlw

Well, there are plenty of threads for how mufflers sound. I would definitely categorize it as loud and aggressive.

SOS's web site has a subjective ranking system. I say they have it right. They give GTLW a 4 out of 10 with 10 being race level sound. I've raced before and you don't want to be near race car loud on the street and 4 out o 10 is almost half as loud. That's still loud.

Search around and you'll find many opinions.

GTLW comes with silencers. I have not tried them, yet.

 

[IsR]

GTLW comes with silencers. I have not tried them, yet.

For me GTLW sounds very good at WOT and its not that loud at idle but it does gives droning sound in the cabin at lower RPM reason why I use my removable silencer in everyday 'non-WOT' driving.
Seen and heard titanium superfour ver5.1, loud but does sound unique but for the price I'm happy that I got my GTLW:smile:

 

[NSX-Appeal]

In total, yes, 20 hp is a significant difference and it would be hard to part with it now that I have it.

I have the Taitec JGTC Center exit exhaust + headers on my '91, and I agree with everything you said. Of course, I've never driven an NSX with stock exhaust, so I don't really have a frame of reference for what it *should* feel like. I just know I love it the way it is.

This system cranks out even higher decibels than your GTLW setup, and I haven't even tried it yet without the cats. I'm almost afraid to street it that way, but we have an autocross coming up and I'll put the straight pipes in then. That should be a real treat for the spectators' ears as well as my own.

 

[clarknm]

I've only had it on for about 1/2 a tank of fuel and I've been fretting over how loud it is more than trying to feel the power gain.

Don't fret too much, give it some more time. I was concerned when I first put mine on (sounded like a civic fart can), but it got much better. I love the way it sounds now.

 

[davidf]

I'll be installing mine this weekend, but I don't expect much gain till I pick up some headers. That won't be very long though.

 

[Easy_Goin']

Don't fret too much, give it some more time. I was concerned when I first put mine on (sounded like a civic fart can), but it got much better. I love the way it sounds now.

I think you just got used to liking a civic fart can. LOL...