DarkFox118

iTrader: (7)

glad I spotted this thread, I havent' gotten to a muffler yet, but I will after I do my LQ4 swap.

LTs and a catted Y. I'm not a fan of loud exhaust, but I'd like mine a little louder than it is stock right now, and my stock tips are sorta falling apart, so I'll have to do something. I was originally just gonna get a LM1 setup but.. guess not now huh?

I try to research things before I buy anyway.

OnlyACamaroCanbeAZ28

So is it the crappy merger that causes the rasp or a lack of a cat (or restrictive muffler)? I just purchased SLP LT's and already have a LM1 catback system. I plan on using a quality y pipe(any suggestions?) into a high flow cat connecting back to my Lm1 catback system. I can hear the straight pipe truck sound in some of the vids and thats not what im going for at all but that is usually caused by the lack of a cat, not because of a "crappy Merger" correct? Id prefer to do my exhaust only once so want to get some things cleared up.

disc0monkey

iTrader: (10)

that's the same question i have. Seems like a quality merge that improves accoustics has been rare for f-bodies until lately. looks like you will be the test mule.

i will bet most of the rasp will be gone

02ws.sik

this is what people need to realize that is a great point.

OnlyACamaroCanbeAZ28

Thats what im betting on too. I was going to do elec cutouts, custom y , single high flow cat, and connect back into the LM1 but it seems for the same money I could have the true duals with dumps. However I still like the idea of loud and flowing (open cutouts) or driveability sound with the electric cutouts closed and everything going to the back of the car with a cat for rasp reduction (still good sound and tone but not overwhelming).opinions?

'00_Z

iTrader: (3)

If you're set on the cutouts I would look into a different cat back. I don't know how big of a single cat you would need to be for it to not be too restrictive but that seem like a lot of things to cram in there between the resonator, custom y and cutouts.
I got a ton of compliments on my LM1 with stock manifolds but after the headers/ory it just plain sucked unless I was running wide open. I ended up with the Hooker cat back and have been happy with it. A good y/merge with a cut out and a decent cat back might work for ya.

NVUSZ28

iTrader: (5)

SSCamaro99_3

iTrader: (1)

I had the LM I years ago.

On a stock car = just fine
Stock manifolds, ORY/LMI = just fine
LT/ORY/LMI = rasp is terrible

A good merge will improve the situation regarding rasp, but will not solve it.
Mike has cats on his LT/ORY/LMI setup. The cast will act like small mufflers and knock most of the rasp out of the system.

You are basically fighting a losing battle because you have 8 exhaust pulses trying to cram down into one pipe. A bad merge makes them tumble/and or fight for space and you get bad sounds. A decent merge will blend them better, but you still get them fighting for space. Cats or a case muffler can hide it somewhat. Duals are the only surefire solution becasue all of the exhaust pulses are in line, and not trying to bang together. LS1's have a different firing order than SBC's, and it seems to magnify the issue.

lemons12

iTrader: (71)

Cats can band aid the issue but they will not fix it.

Crappy merges make for crappy HP and torque as well as tone/rasp/etc..
Go with a quality merge and you will make way better power throughout the power band and your exhaust will sound better.

Flowmaster, stainless works, magnaflow all make good merges. Just depends on what metal you want and what the budget is.

Whichever you go with it should be 3" in and 4" out with a 4" I pipe that has a 4" cutout, reduce down to 3" after that then add whatever muffler setup you want. This will make the most power out of a Y setup by far. This gives the same clearance over the axle also which is nice.

Get a quality merge and you will thank me for it. It is the next best thing to an X or H pipe. They "merge" way better and sound better as well as make more power.... Coincidence?

MikeWS6

Its pointless to even argue what exhaust sounds better. No one is going to change their mind Thats why I dont bother going out of my way to hate on other peoples setups.

TransAmWS.6

Correct. I can see why some people like the sound of these cars with something loud like a Loudmouth catback with a Y-Pipe and I can see why some people like the clean and smoother sound of a lot of true dual setups, it all boils down to a persons personal preference. That's why discussing and debating which exhaust setup is the best is absolutely pointless.

disc0monkey

iTrader: (10)

lemons, do you think the cutout will add some rasp as it will disturb the flow when closed. Pypes had cutouts with a "plug" that actually went into the pipe so the gases will not "see" the cutout when closed to restore the lost hp and accoustical distortion by installing the cutout. With a system that does not filter out any rasp, like the LM1, this may be a concern. what do you think?

OnlyACamaroCanbeAZ28

Okay heres my confusion then because Ive heard a few people say this but doesnt seem right to me. Theres 8 pulses coming through the exhaust. A good merge can help but at the end of the day a merge is still a merge and never as efficent as lets say a TD set-up would be. Why then should I buy a good merge and put the cutout in the I pipe. Thats forcing all 8 pulses together before dumping them instead of dumping them immediately off the LT's. I would think the best power would come off of the LTs right?, not back in the I pipe.

Black00Z

This times 1000000000

lemons12

iTrader: (71)

There is much more that goes into an exhaust making power than this, it is quite complicated honestly.
Different setups will make power different with the cutout in different places.

Differences:
Magna

FM

kooks

Pacesetter

94Z28-MSTGKLR

iTrader: (20)

ARH has a nice merge on their ory. Maybe not the best but better than kooks.

lemons12

iTrader: (71)

Yes they do.

Kooks is a complete garbage design.

SSCamaro99_3

iTrader: (1)

If you look at the merges Lemons showed it is about how the pulses are brought together. The Magnaflow/FM bring them together in a fairly linear fashion. The other two "merges' are bringing the left pulses in at angles to the direction of flow. The pulses effectively bang into the wall of the I-pipe and become turbulent. When the banging and turbulent flow reach a resonance point with the rest of the exhaust you get rasp. Rasp is a flapping annoying sound (trust me I had the LT/ORY/LMI setup years ago). Mine was worst from 2200-3000 rpm, then it would clean itself up. H and X-pipes are far superior to Y-pipe setups. In 1994 Morgan-McClure Motorsports showed up with a Chevy Lumina for the Daytona 500 that had a noticeably higher pitch than the rest of the cars. They went on to dominate Speedweeks and win the race. The were running an X-pipe setup, and everyone else was still using H-pipes. They were more effecient, especially on a restricted engine where moving air and exhaust is paramount.

lemons12

iTrader: (71)

I did not know that... But before reading any farther when you said "higher" pitch I immediately knew you were talking X VS H pipes.

X pipes are where it is at for a modern muscle car. Leave the H pipes for the old school muscle.

LSxWittles

I have LM1 along with slp LTs and o/ry and although it does have rasp, and drones like crazy on the highway I do like it. I will however be changing it out to a different CB or TDs because I am doing a cam swap soon and think the local smokeys won't exactly appreciate the noise lol