About 2 weeks ago I installed my Borla Cat-back for my '05 coupe. Since I have installed it, I have had issues with it vibrating and hitting something on the car. However, I can't figure out what it is vibrating against. I know it is in the rear section of the exhaust, some where around the muffler. I originally thought the passenger side was hitting on the rear anti-roll bar since there was only about 1/8" clearance. I was able to eliminate this because I stuck a piece of rubber between the exhaust and roll bar and the noise continued. The only other thing I can think of is that the muffler is hitting on the metal guard under the fuel tank. I have found that this vibration only happens at lower RPM, usually between 1000-2000, and I have been able to get the vibration by holding the RPM at about 1750.

I have also noticed that I get a squeaking sound when going over bumps and getting a good amount of suspension travel. This is also coming from the rear area.

Finally, I had some issues getting the exhaust installed. I had to modify the driver's side hanger a bit and the driver's side tip still sticks about 1/2" further out, and the clearance between the rear anti-roll bar and the passenger side pipe seems like it is much too small. Not big deals, but I have to say that I am kind of disappointed that the exhaust didn't fit up as well as I expected to.

Sorry for the long post, but the noises kinda **** me off and I would rather try to fix it my self then take it some where and pay like $200 to get it fixed. Your seguestions are very much appericated. Maybe one day I will be able to provide advice to other instead of just asking for it.

 

Had the same problem with mine after the install. Turns out there was 1/2 or so of excess metal on one of the hangers that would vibrate against the pipe at low rpm's. I scored the metal with a cutting wheel and used pliers to bend/remove it. Wala, no more noise.

 

Do you by chance rememver which hanger it was? If not, there are only 4. At least I have an idea of where to look. Thanks.

 

I have had a noise issue with the borla when I had my 03 Gc. The problem with this exhaust is that the instructions totally suck, there is no clear martkings, or any markings on any pieces for that matter. The diagram they provide is almost useless. At first I installed the middle parts of the pipes on opposite sides, they are a bit different bend. That was what caused the noise and it was rubbing/hitting part of the suspension. I had to take the rear part out and switch it over then no isssues at all. I would advise you to get under the G loosen all the connections and hand manipulate the pipes(rotate) until everything is fine, there should be enough clearance everywhere. There is no reason to pay 200 to fix this. I will be installing the borla on my new 05 G within next couple of weeks, hope I dont run into any issues as I have most of the exhaust preassembled and been told it should work on 05 as it did o 03, or does it ?!

 

I'm also starting to have some wierd noise but not sure where. When the car is warmed up completely it makes a sort of sqeakin or hissing noise but when I press 1 side of the H pipe with a towel the noise goes away. Also, I noticed while pressing against the H pipe that it was vibrating a lot. Is it suppose to be doing that?

 

When I first tried install the exhaust I had switched the sections with the pre-mufflers on them. It caused both sides to be long by over an inch. Switching them I could get them to fit, but like I said earlier the driver's side tip is father out. I'll take some pictures tomorrow and post them.

 

The overlap of the pipes is quite a bit, from what I remember about 3 or so inches. So maybe just pull it out a little between all or some of the pipes on the side that stick out less, or hammer it in a litte on the driver side a bit and pull out the other, I am sure you can get it even. This exhaust can definatelly be a pain to put on and look right, but its definatelly worth the sound, I have been missing mine for almost a year.

 

Think.............they come with so many pieces.......don't you expect to have leak now or later on?

 

When I put it on I used some gasket sealant on all the connections but the ones between the muffler and the pipes before that. If you torque the clamps to the specified torque you shouldn't have a problem. I did find that the bolt that holds in one of the hangers on the passenger side had backed it self half way out. See picture 1. When I started my car up after tightening that bolt, it still made the vibration noise when I held the RPMs at about 1750, but after I had the car warmed up, it wouldn't make any vibration noises. It might be that something gets warmed up and no longer is bearly touching something to vibrate aginst. I can live with that.

My dad helped me to get the muffler on and we really got the pipe on the driver's side of the muffler over the previous pipe section really good, it wasn't going on any farther. I was thinking of taking off the muffler and cutting down the pipe leading to the muffler 1/2"-3/4", but then I would have to deal with taking the muffler off and putting it back on. Pictures 2 and 3 are of the driver's side tip and passenger's side tip respectively. You can see how much farther the driver's side sticks out by looking where "Borla" is stamped. Like I said earlier, it sticks out about 1/2" more.

The last picture is of how close one of the pipes is to the anti-roll bar on the passenger's side. There is about 1/8" of a gap between them. The residue you see is where I put some adhesive backed rubber on the roll bar to see if that was causing the vibration issues. It wasn't the problem and the rubber fell of in less than 2 days.

 

I was thinking about buying a borla from a friend 4 500.. now i am second guessing because of these probs... should i? how does it perform> better worse because of b-pressure? please help
!!

 

mjwaterman ... I had same exact issue, I swapped the pipes that are between the resonators and the muffler and all was well. Plenty of clearance on both sides. The tips should come out equal. Unless there is someting uner 05 coupes that is different from 03 coupe that I had the borla on, it should fit right, just needs adjusting. I will probably be putting mine on this weekend, so if I find anything different Ill let you know.

 

Last weekend I did actually find that what was causing the noise is the pipe hitting the anti-roll bar. I sent an e-mail to Borla, but haven't heard back from them, and I honestly don't think I will. I think my next option would be to cut about an inch off each side with a pipe cutter. Not the best solution, but it would work and it would be clean and hard to mess up.

If Gnome gets his on OK, then chances are I missed something and might have to go back to the start and try again.