99ls1zam

i own a 99 trans am i just recently put pacesetter longtubes, pacesetter y-pipe, and slp lm1 exhaust on it (no cats) and its extremely loud. Almost a little too loud for my taste. My question is , is there a different cat back exhaust i could go with not so loud ?

Also i bought a set of bbk ud pulleys mainly all for looks. Will i feel a difference from these? Were these worth the money? And will i have to switch to a difference size belt?

thanks for any help

MikeWS6

Catted Y pipe. Mine is quiet under normal driving/idle.

95 mystic ls

iTrader: (12)

The more 'restrictive' your exahst is, the quiter it is. IMO
LM1 is a pretty free flowing set up. The more restrictive the more power you will prob lose.

USMC5811

iTrader: (2)

are you going to want to sell your LM1 ?

fccs

iTrader: (26)

What were you thinking if you didn't like loud getting a uncatted exhaust with longtubes and a loudmouth 1? lol Switch to a magnaflow catback, they are quieter and still put good power down.

jay7199

iTrader: (9)

get rid of that LM1 POS and get either a LM2 or a dynomax bullet, if thats still to loud for you then you need to get into a chambered muffler..

99ls1zam

it feels like it gave me quite a bit of power . which is a plus. but i will be youtubing some magna flows. if i find the right sound i like and want to buy i will be selling my slp

MikeWS6

What are you looking for? A step below lm1 is probably either lm2 or gmmg.

99ls1zam

i just want something that sounds mean but isnt so raspy. how do i know which i have lm1 or lm2

MikeWS6

I would first try a catted y. It helps ALOT.

I believe the only way to tell is to look through. LM1 is an empty resonator, LM2 has some sound absorbing materal inside.

99ls1zam

it was definately the lm1 then. altho i am complaining about sound i dont want to put cats back on. from what i hear they are a huge power robber. i want every bit of power i can get out of my ls1 just looking for something a little more quiet haha

Blackhawk777

The only time cats REALLY hurt hp is if it's a dedicated track car that needs every last hp you can squeeze out of it. On a daily driven street car if you loose more than a couple hp having cats, then you have other problems besides them. I x3 adding cats first.

DeLaRosa25

iTrader: (10)

Could swap to a magnaflow bullet

egott_91

iTrader: (1)

You could swap in a magnaflow, borla, or dynomax bullet in place of the LM1. You could also get a sweet thunder bullet muffler too.

I have the borla xr1 muffler and I prefer it over my brothers GMMG, which is said to be the best sounding. His has more rasp than mine does and he has a high flow cat in his I-pipe.

T AM

iTrader: (5)

Hack off the lm1 and convert it to a dynomouth, magnamouth, or borla mouth. Those would be cheaper options than buying a catted y pipe.

Pitbull329

iTrader: (3)

Or a hooker aerochamber

BlackScreaminMachine

iTrader: (17)

Thats really a un-true statement as you make it sound to be that if its not free flowing like the LM1, that your going to regret it. Exhaust systems have come a long way and with some of the newer designs that incorporate sound cancelling, it makes a huge difference.

Catted Y pipes like the ones from Dynatech have been Engine Dyno proven to lose at most 1 hp on a stock 6.0L LS2 and maybe 1 or 2 more when moddeded with a heads and cam package.

The LM1 systems is just straigh pipe which may sound good if you do nothing else to the exhaust but as soon as you un cork it, it does get very loud. Also you can forget about a cam install as the sound just get louder.

I have Dynatechs SuperMAXX kit matted with a Corsa and a 228/230 cam in the car and its loud enough where I cannot idle the car in the neighborhood in the morning so I gotta start the car, immediately go down the road and let it warm up. The same exact exhaust system was on a 383 LT1 11.5 to 1 C/R motor with no Cats and it was rediculous.

But in the end its what you want and in most cases no one is at a level of performance where putting on a slightly more restrictive exhaust will make all that much of a difference.

MikeWS6

Some people like louder cars though. Mines not loud enough for me. With cats and a 6 speed the noise is very controlable.

BlackScreaminMachine

iTrader: (17)

Take off the CATS and throw a cam in there with tuning and you will get what you want.

Yes sound is controllable but on a cold day, at idle, my car can wake up my inlaws and some neighbors and we are not that close to each other. So you gotta deal with what you can deal with.

MikeWS6

Thats true. Ill give you that LM1+LT's on a cold start is pretty loud.