9software

I just installed a Borla XR1 Exhaust with the dual pipes. I'm getting a LOT of resonance between 1800-2500 rpms. It's an extremely loud droning noise. Funny thing is the exhaust is quieter at WOT than at the 1800-2500 range. Other than the resonance, it is an awesome system with I've got a 2002 Convertible with no other mods other than the Blackwing.
Most people who have the Borlas are telling me they don't have resonance. Was it a bad install?
Any tips on getting rid of the resonance?

Thanks!
Shawn

wwashing

You've been lied to. XRLs will resonate. Adding an X-pipe will mitigate it some.

Iam_Chief_Wiggum

Install some sound deadening material under the carpet, behind the seats...
This helped alot.

Norris

Check for metal to metal contact. I have a set of Borlas (Quad Ovals) and have no resonance. I love them

Patman36

I am pretty sure that an x-pipe won't fit with the XR-1's. I am pretty sure the only thing you can do is either put in some sound matting under the carpet or swap out the system. :cheers:

Patrick :seeya

9software

Metal on metal contact? Do you think the sleeve where they joined the XR1 to the stock pipes could be vibrating?
You have the quad tips - what system and tips are those? I was under the assumption that Borla didn't make a system with quad pipes...

I will try shoving a couple blankets in the trunk and see if it helps - I was riding with the top off - it helps a little with the top in the trunk blocking some noise but that 1800-2500 resonance makes my head ring.

Will let you know if anything works... =)

Shawn

pjazz

If it's only in 6th gear downshift to 5. Unless you have a A4 :chevy


[Modified by pjazz, 1:25 PM 1/10/2002]

Mean Green

Borla XR1s (dual pipes, no mufflers) will resonate between the rpms you stated....there's nothing you can do short of installing dynomat to mask the sound or "blanks" in the exhaust to tone it done...this will also affect the exhaust note. I've talked to a couple of people way back about going this route.

I've always been upfront with people about the XR1, it will resonate! Anyone who told you different, is hard of hearing :lol:

You can use an x-pipe but you can't use it with the resonator that comes with the system :) :cheers:

Patman36

So if you added an x-pipe (thus cutting out the resonator), wouldn't that really increase the sound? I mean... those are basically straight pipes :jester

Patrick :seeya

Mean Green

that would be right sir :)

TeamZ06

a partition would help, if there is such a thing for the Vert.

geekracer

I installed an H pipe in front of my cats when I did my XR-1 because I heard that it was supposed to quiet down the sound. I have a little resonance at around 2000 RPM with the top up. I have nothing but beautiful sound with the top down :cool:

9software

Hmm...sounds interesting. What H pipe did you use and how much does it cost? How difficult and time consuming was the install? I assume you would have to cut the stock pipes twice to install it?
With the H pipe, does it significantly reduce resonance to the level of a standard 4 tip, 2 muffler exhaust system...it's head splitting now...
I love the look, and the sound of this system...but the resonance has gotta go or the system will go.

I ordered the Borla 4 tip system from Nate @ Xtreme to replace these...any comments on that system as far as noise / resonance and how it compares to the XR1?

Btw, I've been reading this board (but not posting much) ever since I got my '02 Vert back in Sept 01 and I can say it's the most interesting and helpful board around... =)

Thanks!
Shawn

geekracer

I made the H pipe out of a piece if the original H pipe.I split the cats apart and used a holesaw to cut into each side. Then tapered and fit the H sectionso that it exactly fit to the internal pipe. I had a welding shop wire weld it and I installed it.

Unfortunately since I did the H pipe at the same time I don't know how much louder it would be without it. I have never ridden in anyone elses Vette with the XR-1 to compare.

Do you have a coupe? I think that the vert would be quiter anyway because of the soft top and the fact that the trunk is over the resonator and not the interior as in the coupe. It's possible that the shape of the glass on the coupe may act as a 'horn' to funnel the sound towards the front of the car. In this case the sound deadening matting may be the cure.

Good luck with your XR-1. I'm very happy with mine :cheers:

Mean Green

the 4 tip system should include mufflers, I don't think they've started prodcuing the 4-tip xr1, so resonance shouldn't be an issue with that setup :)

jlamay

I've heard about the H-pipe before the cats, and it sounds like a good idea. Mine resonates, but I guess I'm used to it. I have an FRC and I got the trunk divider, and that helped alot. Any good muffler shop should be able to fab an H-pipe on the fly, and it shouldn't cost too much. Hmmm...

BKVIEW4U

what i did was install a gm hot cam and long tube headers, elimated the pup cats with the headers and put in a H-pipe. this made it 50 times worse and i love it . it even resonates alot at idle.......

oh wait.... you said you wanted to ELIMINATE the resonance . oops sorry . dont do what i did

borla does not make a 4 tip xr1 to my knowledge. they do make a rear section exhaust with 2 mufflers just like the factory setup. it has 4 tips

jbsblownc5

I too had alot of resonace in my car and was concerned about the increase in sound since I was going from B&B shorties and the XR-1 to TTS headers Rand. Tech. high flow cats and the Borla XR-1. To my delight the Resonance was noticably decreased due to the cats. The stock cats are a big part of the problem. The sound now is Nascar like :D
JB

davidmax

Common problem asually fied EZ with X-pipe install.For your largest selection and lowest prices give us a jingle.Some vendors will try to sell you a beautful piece there all the same 129.00-300.00.The nicest finished one is by far the Bassani.David S.

levrac68

The 4 tip XR-1s should be out by the summer. I spoke with a Borla rep yesterday.