I've been going around on my exhaust, and I'm thinking I have a problem besides the exhaust itself. It's just too damn loud, even with the stock exhaust (but a high flow cat). I've checked the dizzy and cam timing, I have all new exhuast gaskets. I keep my oil level right. I'm kind of at a loss for what to check next.

Now I have a Sp00n 4-2-1, Carsound, and Mugen Twinloop in there. This should not be so loud as to make my ears ring on longer trips, but it does.

It also seems to change. When the caR is cold, it's usually what I would consider a normal sound level. Sometimes when hot it's much louder, other times not as bad. Any running at revs below 5K really increases the noise, and it takes significant time in VTEC before it starts to purr again.

Is this just noRmal? Perhaps I have a bad O2, although I'm not throwing codes?

Just wondering what to go after before I consider selling the Twinloop and going back to stock. Secondhand R from a machanical idiot, so he could have done anything to it.

 

do you have a resonator on the mid pipe after the cat?

 

That is normal. Exhausts sound louder when the metal heats up.

I think you have very sensitive ears. Your setup shouldn't cause ringing in the ears at all.

I bet if you went back to stock, it would still be loud so I feel that the problem is with your sensitive hearing.

 

my car does the same thing..its nice and toned until it gets hot..then its a sonofabitch..

 

Have you checked the header bolts (holding it to the head) the connection to the cat, etc?

I used to use earplugs after a while on long trips with one of my old exhausts in the ITR ...

 

i ahve a twin loop and a hi flow cat, and my exhaust is so quite. you may just have sensitive ears. i have been playing in a band for 6 years or so so i am just deaf, i guess.

 

Keep it loud, **** the quiet!

 

Yep, checked everything multiple times. No exhaust leaks. Noticed today from the passenger seat, that it's not quite as loud, but still, damn.

One resonator on a Twinloop, two on the stock catback.

It could be sensitive hearing, but frankly, I thought it's not that sensitive any more after years and years of loud cycle and jet ski exhausts.

Is it possible my rubber hangers have hardened (98 R), and it's sounding loud due to harmonic vibration through the chassis?!? They seem decently pliable, but so did a bunch of other rubber parts I recently replaced that turned out to be bad. This was a former Bay Area caR, so the smog likely ate the rubber faster than usual.

I guess I'll next try following the caR while the GF drives and see how loud it sounds to others.

 

I doubt it. Check for leaks by looking for any areas that are blackened OR have someone put their hand over the exhaust to plug it and see if any air comes out of other places.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ill &raquo;</TD></TR><TR><TD CLASS="quote">
Is it possible my rubber hangers have hardened (98 R), and it's sounding loud due to harmonic vibration through the chassis?!? They seem decently pliable, but so did a bunch of other rubber parts I recently replaced that turned out to be bad. This was a former Bay Area caR, so the smog likely ate the rubber faster than usual.

I guess I'll next try following the caR while the GF drives and see how loud it sounds to others.</TD></TR></TABLE>

I think your rubber hanger theory has merit if you changed out the rubber hangers. Mine was nice and quiet when I was only using one rubber hanger mid-car. After I changed all the rubber hangers, and added the second rubber hanger on the b-pipe, the car sounds noticibly louder inside and I can feel the car vibrating from the exhaust.

 

No blackened areas anywhere, but I'll try the plug test. As this is a used Twinloop, could the muff be 'blown out' and louder than it should be? When I bought the car with a hollowed out cat, it sounded loud under car. Now it sounds loud at the rear.

 

If the muffler itself was blown, I would suspect rattling.

 

There are no 'rattles' of any type in the exhasut or the cat, either on, or hand-shaken off the car.

I'm beginning to suspect a problem with the O2 sensor. I'm thinking it's damaged from the former owner running it with a hollowed out cat. It may not even be the stock Acura rear O2.

I'm thinking I'm running a bit rich. Fuel economy is around 275mi or less chock full (e.g. topped off), to low fuel light on intermittent and guage below E. This with mixed VTEC and low RPM town (&lt;30 mph driving). It's often the loudest after running hard, then low-mid RPM's for awhile. Quiets up after more than several minutes VTEC, and very loud right after dropping out of VTEC, especially after some trailing throttle running (downhill).

I believe this is a JDM Twinloop with a true 2.5" cat & header. I will have to confirm, but if I recall there is no bottleneck in the Twinloop B-pipe.

I'll know more in a week after installing my Techedge wideband and checking AFR #'s

It has had a recent valve adjustment by a trusted Acura mechanic, and has great compression numbers. However I am burning quite a bit of Castrol Syntec and M1 5W-30. I am not leaving much soot on the rear bumper however. The car was modded with at least an intake, exhaust, and possibly a header (but no internal mods) by the former owner.

When I got it, he had bypassed the oil breather box by running a hose direct from the valve cover to the intake pipe. I will be replacing the PCV this week. The whole car, including the interior of the valve cover, and the intake/TB were EXTREMELY clean. I get the feeling he never tracked it, just maybe dragged it a little. He got it new at 16 yo from daddy, and treated it as mainly a show kaa.

The power delivery is VERY healthy.

 

Have someone drive behind you and see if they see and/or smell smoke when you go into vtec.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B2FiNiTY &raquo;</TD></TR><TR><TD CLASS="quote">Have someone drive behind you and see if they see and/or smell smoke when you go into vtec. </TD></TR></TABLE>

This would indicate worn oil rings and/or bores, or possible valve/guide damage, and thus oil in the exhaust damaging the O2 / cat?

With daily VTEC, and not overly high oil consumption (judging by HT'rs posts) [&lt;1 qt / 3000 mi], and the tendency of these two syn's to burn off, I'm not sure oil consumption is an overly concerning issue. I'll have the girl drive, and I'll follow. 50K on the R, and I believe the mileage to be legit.

 

It could just be a bad 02 causing the car to run rich.

 

So that would be black smoke for rich, and blue/white for oil?