Low Weight Cat back exhaust
11-19-2002, 08:29 PM
#21
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Wow, an interesting topic. Has anybody measured the hp differences with one or 2 cans?
I'm in the market right now to buy a system so this would really be helpful!!!!!!
I'm in the market right now to buy a system so this would really be helpful!!!!!!
11-19-2002, 09:26 PM
#22
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I've had a few different exhausts on my car, and it looks like you're interested in autocross...
IMHO the best exhaust for the S2000 is the Amuse single. On my car it dyno'd +8hp at peak with gains across the board, while only weighing 8 pounds. It's quite loud, but loud in a good way, and still quiet enough to live with if you like some noise. It sneaks under the db restrictions at tracks like Laguna Seca or the local San Diego autocrosses (92dba @50'). Expensive though.
A straight pipe from behind the stock system's first resonator isn't too loud, and has been done. A straight pipe from just after the cats is waaay too loud - I had one made at a local muffler shop for $80 and only used it a couple times. I like loud stuff more than most people, but it was just abusive to the point of distraction. And it's a LOT of work to swap out at the track.
The stock system does a good job of quieting things down without hurting power. Its downside is the 50 pound weight. I've driven an S2000 with the Mugen exhaust - it's half the weight of the stock system, and a little louder, without any flow penalty. It's what the car should have come with stock, and a good choice if you don't want too much noise.
Right now I'm running a custom-bent 2.5" system with a single Borla XR1 race muffler. The same local muffler guy used some mandrel bends he had lying around to fab a system from the stock system's resonator and back. Total cost ~$300, weight ~16 pounds. The "front half" of the stock system is actually quite good, offering a good bit of muffling, while only weighing about 6 pounds. You'll see it emulated often in other systems, like the dual Amuse.
Lately I've been doing quite a bit better in local events, and I attribute much of it to the lighter exhaust and making sure to only run with ~1/4 tank and the spare tire out. The 100 pounds make a big difference. Now if I could only get back to what I weighed in 10th grade I could compete with Andy - at the scales anyway...
...
My belief is that taking weight out of the rear makes the job of the rear tires easier, for they have less weight to get around a corner for the same amount of tire. Of course it's actually a lot more complicated than that with normal forces and all, but in general lighter is better. I think the key thing is mainly to be accustomed to how the car feels in its lightened state, and to get one's alignment done while in race trim, while sitting in the passenger seat.
...
So Annie, what are you going to do for shocks on the '02?
IMHO the best exhaust for the S2000 is the Amuse single. On my car it dyno'd +8hp at peak with gains across the board, while only weighing 8 pounds. It's quite loud, but loud in a good way, and still quiet enough to live with if you like some noise. It sneaks under the db restrictions at tracks like Laguna Seca or the local San Diego autocrosses (92dba @50'). Expensive though.
A straight pipe from behind the stock system's first resonator isn't too loud, and has been done. A straight pipe from just after the cats is waaay too loud - I had one made at a local muffler shop for $80 and only used it a couple times. I like loud stuff more than most people, but it was just abusive to the point of distraction. And it's a LOT of work to swap out at the track.
The stock system does a good job of quieting things down without hurting power. Its downside is the 50 pound weight. I've driven an S2000 with the Mugen exhaust - it's half the weight of the stock system, and a little louder, without any flow penalty. It's what the car should have come with stock, and a good choice if you don't want too much noise.
Right now I'm running a custom-bent 2.5" system with a single Borla XR1 race muffler. The same local muffler guy used some mandrel bends he had lying around to fab a system from the stock system's resonator and back. Total cost ~$300, weight ~16 pounds. The "front half" of the stock system is actually quite good, offering a good bit of muffling, while only weighing about 6 pounds. You'll see it emulated often in other systems, like the dual Amuse.
Lately I've been doing quite a bit better in local events, and I attribute much of it to the lighter exhaust and making sure to only run with ~1/4 tank and the spare tire out. The 100 pounds make a big difference. Now if I could only get back to what I weighed in 10th grade I could compete with Andy - at the scales anyway...
...
My belief is that taking weight out of the rear makes the job of the rear tires easier, for they have less weight to get around a corner for the same amount of tire. Of course it's actually a lot more complicated than that with normal forces and all, but in general lighter is better. I think the key thing is mainly to be accustomed to how the car feels in its lightened state, and to get one's alignment done while in race trim, while sitting in the passenger seat.
...
So Annie, what are you going to do for shocks on the '02?
11-25-2002, 12:12 AM
#25
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JZR: Have you tried to comptech exhaust? Comptech claimes they get 3hp to the wheels, to me, that seems like nothing if your going to spend a lil over a grand. How much does it weigh?
11-25-2002, 06:05 AM
#26
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Single or dual semi-custom systems built with Supertrapp or Magnaflow silencers with custom bent tubing seems like a great solution... A combination of weight loss, performance increase and reasonable cost.
Both have been done already...
http://www.s2ksocal.com/phpBB2/viewtopic.php?t=1039
https://www.s2ki.com/forums/showthread.php?...ight=supertrapp
Both have been done already...
http://www.s2ksocal.com/phpBB2/viewtopic.php?t=1039
https://www.s2ki.com/forums/showthread.php?...ight=supertrapp
11-25-2002, 06:38 AM
#27
Registered User
I have the J's Racing single. 17lbs, very loud. During a dyno day I had about as much hp as a guy with the Amuse single, and we each only had slightly more hp than the stock cars.
One member has what I think is a great solution - cut the stock exhaust just before the Y split. You retain the side pipe filter that stops ressonance (which my exhaust doesn't have, hence I'll be getting rid of it eventually), it's still plenty loud without mufflers, it offers some significant weight loss, plus it's FREE.
One member has what I think is a great solution - cut the stock exhaust just before the Y split. You retain the side pipe filter that stops ressonance (which my exhaust doesn't have, hence I'll be getting rid of it eventually), it's still plenty loud without mufflers, it offers some significant weight loss, plus it's FREE.
11-25-2002, 08:03 AM
#29
Registered User
Acceleration equals Force divided by Mass. Reducing mass is the easiest way to improve acceleration without major modifications to the engine. Plus, decreased mass requires less tire and less brake for the same performance.
Here is a Single Exit Exhaust that I built for auto-x:
https://www.s2ki.com/forums/showthread.php?...&threadid=92701
Here is a Single Exit Exhaust that I built for auto-x:
https://www.s2ki.com/forums/showthread.php?...&threadid=92701
