hmm... too much rasp/obnoxiousness
Thread Starter
Launching!
Joined: Jun 2006
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hmm... too much rasp/obnoxiousness Ok i have a 2000 trans am ws6 m6,, mods are just boltons (headers/ls6 intake lid etc.) well i have an ORY with no cats and with the exhaust running straight through my GMMG exhaust it doesn't sound so good.. I have a whole lot of rasp and it really doesnt have a deep tone that it had before the headers. my question is, should i just go ahead and bite the bullet, sell my gmmg and get another catback? or should i put a bullet in the I pipe before the pipe goes over the axle? and how long of a bullet muffler would be needed to kill the rasp but not quiet it down so much that it's quieter than it was before the headers? i love the car being loud, but the sound/tone that it has is garbage in my opinion... i've listened to almost every video/sound file on ls1sounds.com by the way 
thanks in advance, all opinions appreciated
michael
thanks in advance, all opinions appreciatedmichael
I've yet to hear a good sounding GMMG with an ORY. All exhausts sounds good at idle and a free rev.. its that driving under part throttle that all the rasp comes in. All LT header and Catted Y pipe setups I've heard sound good so I'd just add a couple Magnaflow spun cats to the Y pipe. The other options is to get a custom ORY Pipe with a Flowmaster Merge. the really smooth merge really cuts down on the Rasp.
You could also add 2 or more bullet mufflers to the exhaust. Keep this in mind... I recently weighed a Dynomax Bullet muffler 18" long 4" dia it weighed 10 lbs 6 oz. A high flow magnaflow Spun Cat weighs 2 lbs 5 oz. imo.. I'd rather Add a couple cats and gain 5 lbs and loose 3-5 hp than add a 20+ lbs of mufflers in hopes of saving those couple hp. Less weight helps on all aspects of a cars dynamics while hp only helps in acceleration and imo the tiny hp you save going with running extra mufflers is completely negated by the added weight.
You could also add 2 or more bullet mufflers to the exhaust. Keep this in mind... I recently weighed a Dynomax Bullet muffler 18" long 4" dia it weighed 10 lbs 6 oz. A high flow magnaflow Spun Cat weighs 2 lbs 5 oz. imo.. I'd rather Add a couple cats and gain 5 lbs and loose 3-5 hp than add a 20+ lbs of mufflers in hopes of saving those couple hp. Less weight helps on all aspects of a cars dynamics while hp only helps in acceleration and imo the tiny hp you save going with running extra mufflers is completely negated by the added weight.
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
Read my posts in the thread below you beginning at #9. https://ls1tech.com/forums/generation-iii-external-engine/945581-my-car-has-been-very-busy.html
The sound of ORY/GMMG is beyond horrible because the rasp is so extreme. It takes a lot to get rid of it. But the end result can be awesome sound.
If you don't want cats, you can go with a Hooker or Magnaflow. It's much cheaper than adding all the pieces necessary to making your GMMG work. And you'll come out ahead selling your GMMG. But I tried a Hooker for a while. It was much quieter, but some rasp still got through.
The sound of ORY/GMMG is beyond horrible because the rasp is so extreme. It takes a lot to get rid of it. But the end result can be awesome sound.
If you don't want cats, you can go with a Hooker or Magnaflow. It's much cheaper than adding all the pieces necessary to making your GMMG work. And you'll come out ahead selling your GMMG. But I tried a Hooker for a while. It was much quieter, but some rasp still got through.
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
I agree and I think I ended up with one of the heaviest exhaust systems in the LS1 world making my GMMG work with LT's. The GMMG isn't light to begin with. I didn't weigh the powerpack I have in my I, but that thing is heavy also, as are my resonator tips.
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On The Tree
Joined: Apr 2007
Posts: 152
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From: Clemson, SC
Ok i have a 2000 trans am ws6 m6,, mods are just boltons (headers/ls6 intake lid etc.) well i have an ORY with no cats and with the exhaust running straight through my GMMG exhaust it doesn't sound so good.. I have a whole lot of rasp and it really doesnt have a deep tone that it had before the headers. my question is, should i just go ahead and bite the bullet, sell my gmmg and get another catback? or should i put a bullet in the I pipe before the pipe goes over the axle? and how long of a bullet muffler would be needed to kill the rasp but not quiet it down so much that it's quieter than it was before the headers? i love the car being loud, but the sound/tone that it has is garbage in my opinion... i've listened to almost every video/sound file on ls1sounds.com by the way thanks in advance, all opinions appreciated
michael
thanks in advance, all opinions appreciatedmichael
I have hooker long tubes, into a TSP ORY then into a cutout. If you put the car under any load it sounds like absolute ***! Let me know if you find a way to solve this problem.
I've yet to hear a good sounding GMMG with an ORY. All exhausts sounds good at idle and a free rev.. its that driving under part throttle that all the rasp comes in. All LT header and Catted Y pipe setups I've heard sound good so I'd just add a couple Magnaflow spun cats to the Y pipe. The other options is to get a custom ORY Pipe with a Flowmaster Merge. the really smooth merge really cuts down on the Rasp.
You could also add 2 or more bullet mufflers to the exhaust. Keep this in mind... I recently weighed a Dynomax Bullet muffler 18" long 4" dia it weighed 10 lbs 6 oz. A high flow magnaflow Spun Cat weighs 2 lbs 5 oz. imo.. I'd rather Add a couple cats and gain 5 lbs and loose 3-5 hp than add a 20+ lbs of mufflers in hopes of saving those couple hp. Less weight helps on all aspects of a cars dynamics while hp only helps in acceleration and imo the tiny hp you save going with running extra mufflers is completely negated by the added weight.
You could also add 2 or more bullet mufflers to the exhaust. Keep this in mind... I recently weighed a Dynomax Bullet muffler 18" long 4" dia it weighed 10 lbs 6 oz. A high flow magnaflow Spun Cat weighs 2 lbs 5 oz. imo.. I'd rather Add a couple cats and gain 5 lbs and loose 3-5 hp than add a 20+ lbs of mufflers in hopes of saving those couple hp. Less weight helps on all aspects of a cars dynamics while hp only helps in acceleration and imo the tiny hp you save going with running extra mufflers is completely negated by the added weight.
Basicly you need some sound absorbing material like found in Magnaflow, Hooker, etc. Just some dents or ridges or baffles will not do it. You need to knock some of the bark off of it. An LS1 doesnt need any help making rasp so you have to choose your muffler(s) wisely when running an ory.
Add cat's to the Y-pipe or get a magnaflow. I advise you to hear actual cars with the set up you want before you do it. Not just listen to files on line. There is a big difference in person.
Teching In
Joined: Jun 2008
Posts: 14
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From: reading,pa
If you decide to give up the GMMG hit me up I want one of the chambered set ups like you wouldn't believe. I heard a magnaflow without converters at the carlisle event and it was sweet. a little too loud for my wifes car so we are keeping the cats and going with the magnaflow. I have a flowmaster on my 98 with some mac headers and high flow y pipe. If you want a flowmaster as a partial trade maybe we could work something out. Let me know.
Thread Starter
Launching!
Joined: Jun 2006
Posts: 296
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ok, thanks for all the responses so fast , i was looking at either a borla xr-1 but borla seems to be pretty high normally.. or a magnaflow bullet a buddy of mine has the same setup i'm looking at right now(with the bullet in the i pipe before the gmmg catback) and i'll be listening to it tonight. i try not to go by videos because most peoples videos cant capture most of the tones and to me most of the videos of idle's and people revving up different setups just sounds horrible because of that... or maybe its just my speakers 
one of the main reasons i didnt want cats was A. cost and B. if you get a cheap one, its not going to flow worth a crap (from what i've read)
well i'll let you guys know what i end up doing..
and thanks alot again for the quick posts and all your info
michael
btw 98silverttz if i end up going the route of selling my gmmg i'll let you know
, i was looking at either a borla xr-1 but borla seems to be pretty high normally.. or a magnaflow bullet a buddy of mine has the same setup i'm looking at right now(with the bullet in the i pipe before the gmmg catback) and i'll be listening to it tonight. i try not to go by videos because most peoples videos cant capture most of the tones and to me most of the videos of idle's and people revving up different setups just sounds horrible because of that... or maybe its just my speakers one of the main reasons i didnt want cats was A. cost and B. if you get a cheap one, its not going to flow worth a crap (from what i've read)
well i'll let you guys know what i end up doing..
and thanks alot again for the quick posts and all your info
michael
btw 98silverttz if i end up going the route of selling my gmmg i'll let you know
i've got lt's no cats an H true dual setup with LM1's before the axle and out the back . . . before i had the crossover pipe ut in it was really really raspy! but now it's not as bad, still some rasp but i love the sound of the car now
Thread Starter
Launching!
Joined: Jun 2006
Posts: 296
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would an oval borla xr-1 in the i pipe before my GMMG kill my rasp? and does the oval xr-1 muffler quiet it down too much? I'm thinking an oval xr-1 would make it real deep but little on the quiet side.. but then again i've never heard one in person.. anyone with experience on the borla xr-1 oval muffler?
thanks,
michael
thanks,
michael
