350350

Long story short, Wife totaled my '95 LT1/M6 car and it had a single cat setup with an SLP LoudMouth CAT-Back on it. The car still runs and I bought it back from the insurance company to swap the powerplant into my '78 Malibu. So I actually started it up next to my '97 to compare the two!!! I swear the '95 is louder! I know the CAT is NOT gutted, as I looked inside it when I was putting the LoudMouth on it.

So I finished putting the LoudMouth on my '97 SS tonight and I SWEAR it's quieter! Noticeably quieter! So I'm thinking to myself: Which SHOULD be quieter? A y-pipe with a cat on each leg, or a y-pipe with a big cat in the crotch of the 'Y'??? The two LoudMouths are otherwise identical. The '95 has an extra 'S' in it where the CAT is offset to the passenger side a bit and the S takes the pipe back over to center to mate to the LoudMouth's generic location.

Am I crazy? Or should I have expected the dual CATs to quiet the system down significantly? It still sounds really nice, and at WOT of course it sounds awesome, but it just isn't nearly as loud.

Green94GT

I'm pretty sure that's normal. My 94 Z28 was definitely louder than both my 96 and 97 Trans Ams. All were stock.

Bersaglieri

Ye-haw single cat F-bodies! Wait I dont have any, but still Ye-haw its loud!

I would figure the dual to be quieter, kind of like having one muffler would be louder than having two mufflers.

-Dustin-

2000LS1Z28

First off, did you say all things are otherwise equal (both have stock internals, manifolds, & cats) while both running the SLP Loudmouth systems? Is your '95 louder at idle too? I found this thread which the original poster is experiencing the same thing compared to his friend's single cat car...

http://web.camaross.com/forums/showt...ghlight=cutout

But personally, I've never thought my single cat LT1 is that loud with the GMMG cat-back IMO. My dual cat LS1 with the GMMG & longtube headers is about the same at idle, but a LOT louder at WOT! Granted it does have headers. Although I'm having some Mac headers with a bullet in place of the cat installed soon on my LT1. That will more than wake it up!

Mike

Bersaglieri

Bullet? How about Off road pipe? I guess the one LT1 with MAC's and no cat was too loud for you? Brians was it?

I like the way my car sounds with LT's and GMMG. It impresses the hell out of people and I enjoy doing that. But its making me deaf, its starting to sound quieter each day and I cant get my Bose to play loud enough to hear over it

-Dustin-

jchevy

The cats act like mufflers, so yeah, its normal for the dual cat car to be quieter.

Wicked93Z

I love the way mine sound. Has a nice deep rumble at idle. But loud as hell at WOT. Heaven forbid if I pull into a parking garage. The trail of car alarms going off kind of give me away. Not intentionally though. I just get beside myself sometimes.

350350

Yeah, all other things being equal, except the '95 is a Z28 with a SLP CAI and the '97 is an SS with Ram Air, but I can't imagine that would make any difference in the exhaust note. Both have stock motors. I'll check out the link...

When I told my Wife I thought the SS was quieter, she said, "I don't think 'Quiet' is a word I would use to describe it."

All a matter of perspective!

2000LS1Z28

I'm going with the bullet because Bob's LT1 with the offroad pipe made the car sound a little raspy in the mid rpms...It wasn't a bad sound, but I want something cleaner...The bullet in place of the cat will negate any rasp and make for a little deeper sound (and is nearly as loud as the race pipe).

Loud? I love LOUD (as long as it's a good loud). And I know the GMMG will become a lot deeper & louder once the headers go in. Bob's car can attest to that and he only has a stock internal motor.

350350

I guess the important thing is that it sounds awesome and flows much better than the hack job that it all replaced!

http://web.camaross.com/forums/showthread.php?t=332526

But we all know that the most important thing is the fun factor, which is definitely there with the new exhaust. The system before this was quieter than your Grandma's Buick!

And to put it all into perspective, tonight I put a CD player in place of the factory cassette deck that my car came with. As with any modification, no matter how trivial, a Test Drive was in order. Having an unseasonably warm day here in the Carolinas, almost 70 degrees, my 4.5 year old son wanted to go with me and he insisted on taking the T-tops out! (Like he had to twist my arm...)

So we went through the country a couple of miles with the stereo blaring and the wind in our hair (The Boy also insists on the radio LOUD!) and then came back home the same 2 miles on the interstate. So we had the opportunity to take some winding country roads as well as get up some interstate speeds, all the while being able to get all over all 6 gears and listen to the LoudMouth through the T-tops.

When we got home, The Boy and I were walking into the house and he said, "Dad, your SS Camaro goes Super Fast. It's Super Cool!!!"

So not only do I have the fastest car in the whole world (according to my Copilot), but I'm the coolest Dad EVER, at least to one Little Boy... So even if it's not as loud as other LoudMouths or if my Camaro isn't the fastest Camaro in town, it's still got the AAA+++ approval of my Copilot, which is more important anyway...