road_warrior

im currently searching for what exhaust to go with. i was planning on doing something similar to the loudmouth or tsp rumbler, but was planing on using 4 inch pipes instead of 3. it will be custom made.
how many of you guys have gone with 4inch instead of 3, whats the sound like, lost or gained hp or tq?

White Trash Camaro

It all depends what muffler you go with. A 4" Bullet would be loud as ****** ****. Sweeeeeeet!

goober35

iTrader: (1)

I have a Hooker Headers with a 3in QTP Y with Dual cut outs to a 4in mufflex system with a Magniflow muffler. Sounds is bad ***. Some drone in the car. I dont know if i picked up or lost any TQ/HP because i installed it with my new iron 370.

hc_performance

iTrader: (4)

IMHO 4" would prob. be overkill unless you had a whole lotta cubes!!! You would prob. loose tourque all over but it would sound mean!!!!

SpdfreakLS1

iTrader: (2)

I also have hookers to a 4 inch with a 3 inch straight through magnaflow. Heres how it sounds
http://67.15.56.43/~spdfreak/Videos/..._magnaflow.wmv

1999nbmZ

Where do you get the 4" y-pipe and exhaust system that gmmg uses?

MeentSS02

iTrader: (11)

What exactly is prompting you to go with a 4" pipe? The whole "bigger has to be better" thing? Just wondering...that's a pretty big exhaust to be running on these cars.

1999nbmZ

Well, I'm planning on running a 427. Figured if GMMG uses 4" y-pipe back, so should I.

MeentSS02

iTrader: (11)

Okay, I see where you are coming from, and it would probably be a good idea on a motor like that. Sorry I don't have any experience with it though 2.5" true duals here...

MIGHTYMOUSE

iTrader: (59)

i run a 4" intermediate pipe to a single 4" dynomax bullet w/ turndown

getting a 4" cut out made right now

1999nbmZ

So Mightymouse, are you running a y-pipe setup? If so, what y-pipe. All I have seen is the 3" outlet y-pipes. Also, where did you get the 4" intermediate pipe?

road_warrior

im not sure if mufflex makes 4 inch y pipes for LS1s but i know they make them for LT1s. you should do a little search see what you come up with. they might have them.

MIGHTYMOUSE

iTrader: (59)

i dont have a y pipe i have a turbo.. its all different stuff, i jut thought i would chime in

99'Formula

iTrader: (7)

4" is not over kill. I had a Borla, Magnaflow, and True duals (all 3"). Now I have a Mufflex single 4" system with a Magnaflow. Which dynoed the exact same horsepower as the true duals and 5 less torque than true duals (Pretty empressive for a cat back if you ask me). There's your proof that 4" is not in anyway to big for stock cubes. People use two 3" pipes for true duals so why is one 4" pipe to big?
Here's some pics of my setup.

Fast Toys Performance Parts

iTrader: (3)

Mufflex makes the only bolt in 4 inch exhaust system for the LS1 Camaro/Firebirds. They offer two choices of mufflers being a Flowmaster Race muffler or a Spintech street muffler. A 4 inch system works great on power adder or heads and cam cars.

If people are interested, we could set up a GP

99'Formula

iTrader: (7)

I highly recommend the mufflex system with a Magnaflow upgrade. It only cost me $40 more to upgrade it. FYI

bigeller

iTrader: (2)

I'm another fan of the Mufflex 4" system.. I ran the Mufflex 3" into 4" Y with 4" all the way out Spintech muffler.. Made great power for an A4..

blind527

iTrader: (8)

I highly recommend Random Tech's cat back systems, they are very nice.

racrx

MUFFLEX!!!!!!!! Call them, they can fabricate anything, really. Ask for Denny.
peace,
Victor

msbz_ls1

iTrader: (1)

never heard of 4" exhaust til this thread...hmm..sounds like a good idea though