SLPCAMAROSS

I know this GMMG question has been passed around a lot but all i want to know is if your still gonna get any rasp with LT'S + ORY + GMMG instead of SLP LM. It it worth the swap? The SLP LM setup looks pretty much the same to me as the GMMG except for the dents in the piping?! also... I dont wanna mess with any borla xr1/dynomax i dont like the sound too much. Thanks!

lilbuddy1587

iTrader: (1)

Either way, you're looking at rasp. So just throw some high flow cats on and call it a day. You won't see much of a loss in power/tq if any at all unless you're cam only or H/C and even then u still wont see much of a loss if any

SLPCAMAROSS

Thanks man, what's the best high-flow cat available? Any suggestions?

Z28Venom

iTrader: (13)

Random Tech

16nrollininaws6

Theres a big difference between GMMG and SLP. Just use cats and dont deal with the rasp. LT's/Catted Y/GMMG is my favorite set-up.

FastFrank

i dont get why there is so much rasp out of GMMG and LT's?? Whats with it?

SLPCAMAROSS

Im guessin' its cause theres no muffler on both (GMMG & SLP LM) & with the LT's added to that... theres hardly any air restriction

Damian

iTrader: (89)

Every LS1 is raspy when you remove the cats, it's not just GMMG.

To help quiet down/fix the rasp without adding cats, I recommend adding a Flowmaster 3.5 collector to your Y-pipe. When I did this to my car, the rasp went away COMPLETELY. I am running a Hooker muffler so it's a tad different ball game since it's an actual muffler system, but i'm willing to bet this will cure most of your rasp ills with the GMMG.

FWIW, every LS1 exhaust has some rasp with the cats removed.

bluecmaro96

i finally got my longtubes on monday morning and i knew it would be a difference with the gmmg but i had no idea it would be this incredible. i had a 00+ black ws6 pull up beside me and he revved it, sounded like flowmaster, either way it was just exhaust system, i revved mine and he yelled over and said my car is the best sounding ls1 he has ever heard and said it sounds even better than his cousins true dual ls1. i doubt it does but thats what he said. i kinda want to add a decent cam because now i have this great sound i think it would be awesome to have that sweet chop im more than happy with my setup and adding longtubes made my car have that awesome muscle car rumble.

SLPCAMAROSS

Awesome man, glad you like your LT's! Do you have Cats on the car or ORY? Is the car Raspy at all with the LT's & GMMG?

bluecmaro96

im running the jethit cats, no rasp, its a very deep rumble, actually sounds like a race car now, cant wait for cam. the only problem i have is the heat shield for the gas tank vibrates sometimes at like idle, ill remove that. i wasnt gonna mod the trans am too much like i did my v6 camaro with heads/cam/ custom longtubes etc. but now after i hear this car i want a nice cam. lol

FastFrank

so for all you LT + GMMG guys its best just to get the Emissions friendly headers W/catted Y pipe?

Hardtop00SS

iTrader: (17)

I have LT's, Mufflex Y with flowmaster collector, with GMMG and it's pretty raspy between 1800-2100, but after that, it's sounds fuggin awesome!!!

KrazyDan

i have kooks lt's with catted y and gmmg. It sounds awsome. before the lt's you get that little bit of drone around 1800-2000 rpm. after the lt install its just sweet music. And amazingly loud at WOT