BAD XXX

Since I have the Magnaflow muffler, I thought that an ORP would be cool and not suffer from rasp. WRONG! The rasp between 2200-2400 rpm's is horrible. I have mid-length headers and a cam. It sounds great otherwise, but that rasp sound like ****. The ORP made a huge difference in the sound. Looks like a bullet muffler is in my future. Has anyone not had success installing a bullet to reduce the rasp?

TaTommyWS6

I have the exact same setup. I've been living with the rasp for a while now... It's funny though, I used to have LM exhaust and the rasp was a lot worse. At least with the Maganflow you could calm the rasp down a bit if you give it just a little throttle during the dreaded 2200-2500 range. With LM it ALWAYS had a horrible rasp.

I think two bullets (where each cat would be) is the best way to go. I have resisted doing this because I am not sure if I am going to need to put cats on in the future anyway come inspection time.

Good luck.

Tommy

LPCWS6

What exactly is rasp. I'm a newbie so excuse me if it's dumb question, but I would like to know because I'm thinking of putting headers and a ORP on my car.

BAD XXX

Rasp is a sound that is inconsistant with the exhaust note. It is higher pitched and quite louder, and usually happens within a narrow rpm range. I believe that is is a resonance frequency. Guys claim that a true-dual exhaust will prevent it. I hate it.

John02SS

iTrader: (47)

I put a 16inch bullet in the I pipe before the cutout and got rid of about 95% of the rasp. LT's, off road y, and B&B Triflow.

BAD XXX

Really! 95%! I will be the happiest guy in the world if it works that well for me. Has anyone tried any other 4" muffler besides Dynomax? I still have the 2-3\4" rear pipe, hope I can find those inlet/outlet sizes. I heard some guys have used a chambered muffler, I wonder how that sounds?

MyLS1Hauls

iTrader: (2)

I'll tell you this...I have LTs with cats in a custom Y with a Flowmaster collector and a Magnaflow muffler and it still makes that noise...its quieter than just straight off road, but its still there and I HATE it. I tried 2 bullets and they were no good, so I went to cats.

Mike K.

I just switched to duals cause of the rasp after I put on my Hooker headers and hooker y. I was thinking maybe it was the y but if you guys have the flowmaster y it must not be that? Whats even more funny is with my slp lt's and y I did not have any rasp. I was using the hooker catback with both setups before I went dual as well and I think that muffler is one of the best at eliminating rasp.

Ryan02SS

iTrader: (3)

I put a 18" long Magnaflow bullit muffler in my I pipe to also reduce the rasp and it did a really great job. There is still rasp when you let off the gas at high rpms but it did totally eliminate the rasp around 2200-2600 rpms you were talking about.

Kurtomac

iTrader: (5)

if you have a catted mac y pipe put that back on and gut your cats out a friend of mine tried putting a off road mac y pipe with his magnaflow on and it sounded like **** with his magnaflow he gutted his catted y pipe and he said "its probably the best sounding car ive owned" give it a try cheaper than buying bullets or trying anything else

BAD XXX

No way Kurt, I need those cats for my emissions thing here in Cali'. I am going to install a bullet muffler, I gained 1" ground clearance with the ORP, that means that I can lower the car a little more, so it is worth my while and bucks to set the car up for an ORP. I will kill this rasp if it's the last thing I do.

CySevans

The horrible rasp is exactly what prompted me to go with the duals. You think it's bad going through mufflers? Try it through a wide-open Borla.

Nine Ball

iTrader: (38)

Borla and offroad Y is THE worst sounding LS1 system ever. Its terrible with the echoing rasp from hell. Think of a ricer with a louder exhaust for an idea of what it sounds like.

SLP dual-dual muffler will get rid of the rasp and make just as much power as any other catback. I love this setup (had it on my Formula also)

You can also install a Borla XR1 straight-thru muffler in the midpipe, it will kill the rasp. Pricey mufflers though

Tony

minivette

I have Macs ORY with Dual-Dual and I don't really have any rasp at all.

bryan c

Nine Ball, what exactly is the SLP dual-dual muffler catback you refer to? I'm looking for a catback system and I don't want a raspy one.

Jason99T/A

iTrader: (21)

I had MAC headers w/ off-road, 3" Dynomax bullet muffler in the intermedate pipe and a wide-open Borla about 3 years ago and still had a little rasp. The 3" bullet muffler really got rid of 75% of the rasp, if not more. Here is a sound clip at WOT:

http://members.***.net/jason99ta/eunice1211.mpeg

This was with the MTI B1 cam, 4:10s, and stock LS1 intake.

Jason

WicketMike

iTrader: (13)

i have hooker LTs, ORY w/ no cats and a cutout
and the rasp between 2200-2500 is horrible also
but even since i got the 3200 vig. i jump right by it most of the time now

Nine Ball

iTrader: (38)

72sub, the SLP "Dual-Dual" is the factory catback for all Pontiac Firehawks, and was the optional exhaust for the SS Camaro. SLP sells it, as well as most of the sponsors here that carry SLP products. Here is a link:

http://www.slponline.com/view_produc...RTNUMBER=31029

Tony

Jason99T/A

iTrader: (21)

The SLP dual/dual and the MAC headers with ORP is one of the best sounding setups, hands down. I had a friend with an '00 SS that intalled this exact exhaust setup on and he couldn't have been happier.

Jason

BAD XXX

Really cool video Jason. I called my girlfriend up to the computer room to watch the clip at full volume, and she got a little squishy watching it (she loves hot cars). Thanks.