FAST LS1

iTrader: (2)

I've fought with rasp for a long time with my loudmouth after I put in LT headers and an ory-pipe. First I got the bullet muffler welded in place of the hollow echo chamber that comes stock on it, that did little to nothing. It took the edge off the loudness, but was still very raspy. Next I had 2 sweet thunder chambered mufflers welded in replicating the GMMG style exhaust. It took a little more rasp out, but it was still just barely an uprgade. Finally I ordered the "expensive" $120 Borla XR1 muffler and welded it in place of my bullet.

I wasn't expecting much and I was happily suprised to hear 99.99% of the rasp GONE!
Anyone that has a Loudmouth should seriously do this as their first and last mod if they ever have headers and an ory-pipe.
I can hear a slight tinny sound where the rasp use to be like a damn machine gun, but it's hardly noticable compared to how bad it use to be. Also it only makes the slight tinny rasp in the heart of where the rasp use to be. It has made the exhaust a lot more quiet since there's no rasp, but it's still decently loud. I didn't even install the flowmaster y-collector yet that I also have, but I probably will to see if that kills the rasp completely.

So in short you can fix a loudmouth with a borla XR1 muffler even if you have long tubes and no cats.

Edit: Here's a link explaining the swap: http://www.javagator.com/z28/images/borlaslp/

Link to what the muffler looks like inside: https://ls1tech.com/forums/showthrea...ight=Borla+XR1

jermstyle

I think I will order an XR-1 tomorrow. I had a catted Y with the LM + LT’s and it sounded great. I dumped the cats and installed an ORY and now it’s a little interesting. Not really digging the machine gun sound you mentioned, mine isn’t even a d-driver and it gets very annoying.

Ferocity02

iTrader: (60)

Yep, fiberglass = rasp killer. I could of told you that before you bought all of those mufflers!

DanZ28

iTrader: (5)

So, no clearance issues with the XR-1? What part ##?

Thanks,
Dan

SLP LS1

I have the loudmouth and soon headers. I don't think I'm going to take the chance on ruining the sound of my car. Probably just go with a custom setup of true duals. But, thanks for the info man!!!

2MuchRiceMakesMeSick

Is it still loud? Or does it just seem like a regular exaust?

Z28Venom

iTrader: (13)

Borla Part Number 40085

It's also not a fiberglass filling inside of the muffler. It almost like stainless steel wool. This stuff never burns out like fiberglass.

The Borla removes all of the rasp, but remain most of the loudness. It just sounds a helluva lot better.

jermstyle

Who would like to take a guess at how much power this will cost me?

I just picked up 7hp and 10tq by swapping to a ORY and I'd like to keep it if at all possible.

FAST LS1

iTrader: (2)

There was a little clearance issue and I beat the floor pan up a little, maybe half an inch in over a baseball sized area. Other people have fit it with out a problem.

http://www.javagator.com/z28/images/borlaslp/

The car is still loud, but with the rasp gone it seems much more quiet. I doubt any other catback will flow as well as a Borlamouth since the Borla XR-1 muffler is a straight thru 3" design with only a perferated divider plate to push the sound into the muffer.
Here's a link to what it looks like internally https://ls1tech.com/forums/showthrea...ight=Borla+XR1
Of course true duals will still flow better, but for a 3" catback I doubt you'd loose almost any hp changing the resonator out for the XR1.

z98

Why bother buying the loudmouth only to replace the resonator?

Why not just buy the borla and have a muffler shop make one for you?

FAST LS1

iTrader: (2)

It's probably cheaper to buy the Loudmouth for ~$350 and weld in the $120 XR1 muffler. The LM is a fully stainless steel mandrel bent exhaust, there are only a few muffler shops in the country that can even do mandrel bends let alone stainless steel mandrel bends.

z98

More than a few do mandrel bending!

But good point on the stainless.

Z28Venom

iTrader: (13)

It won't cost you any HP. The muffler is a straight through design just like the bullet and resonator in the Loudmouth. It just has a bit of stainless steel wool around the outside to help muffle.

chris2000ss

iTrader: (9)

I ordered a borla xr-1 the other day...I have the LT'S,ORY and LM with a dynomax welded in place of the resinator,way to shity raspy sounding...cant wait to get the borla on!!!

riddler

iTrader: (4)

Yup, I've got a Borla XR-1 sitting in my living room waiting to go on. I can imagine how bad that rasp must be. I have Long Tubes ORY and the Texas Rumbler with the Dynomax Muffler and I was thinking about changing my license plate to read 50 CAL for a while