Like most other new LS1 owners, I want a more agressive exhaust (both sound and performance). I have listened to the many sound files posted at LS1 Sounds and really like most of them!

I doubt my SS will ever see the track, but I will pay for more useable/streetable horsepower - beginning with the exhaust. With that being said, I have only two restrictions. One, I will opt for a cutout, but don't want an EXTREMELY loud, cop stopping exhaust or a drone at highway speeds when the cutout is closed. Two, I want a dual (not quad) CME. Other than that, I'm open to all scenarios.

After a ton of research, I'm leaning towards a true dual set up (if I can get away with it) with LT's. However, I live in an emissions restricted county here in Texas (Dallas). I'm assuming that means I've got to live with the cats. I will also be lowering the car which I know through my research restricts the options for headers.

Can anyone help recommend a setup for me given these parameters? This will be one of the first mods I make - if not the first. Thanks, in advance...

Rob

 

I doubt my SS will ever see the track, but I will pay for more useable/streetable horsepower - beginning with the exhaust. With that being said, I have only two restrictions. One, I will opt for a cutout, but don't want an EXTREMELY loud, cop stopping exhaust or a drone at highway speeds when the cutout is closed. Two, I want a dual (not quad) CME. Other than that, I'm open to all scenarios.

Ok, if you get a cutout, it will be loud when open, and quiet as stock when closed and it will net you the same sort of gain as a cat back. (only for stock motors) If you don't plan to do bigger and better things, the cutout will be just fine. If you do want to do big mods then know this, you will retain the stock I-pipe setup. LT Headers and cams need to benefit from free flowing exhaust and basically you'd be cramming all this velocity at the primaries into this little shitty I-pipe... Not really optimal... This is where catback systems come into play. MOst of em expand the I to a 3" system and flow pretty well for all sorts of setups. you said you wanted the CME, which gives you a different thatn stock look and also will provide a little more breathing ability for future mods. Some people do dual cutouts on their Ys but unless you're running big cubes, there's really no reason to do this other than sound (in some cases it actually does not benefit the motor due to lack of backpressure). If you just wanna do bolton mods, i say go for the cutout, it's cost effective and will support light modding. If you plan of heavily modding, you should do everything you can to open your exhaust up (true duals, catback, LTs, etc)

After a ton of research, I'm leaning towards a true dual set up (if I can get away with it) with LT's. However, I live in an emissions restricted county here in Texas (Dallas). I'm assuming that means I've got to live with the cats. I will also be lowering the car which I know through my research restricts the options for headers.

Find a "friendly" shop if you do TDs cuz all TDs are considered illegal (since they dump before the axle) This will be the best sounding setup and most free flowing but depending on your mod level may not be optimal for backpressure. If you plan on keeping cats, then i wouldn't even worry about a true dual setup unless all you want is sound... You'll already be illegal anyways, might as well take the cats off too... And for LTs and lowering, just stay away from SLPs, while they make a good LT, they have shitty clearance... FLPs and the Dynatech Supermaxx LTs have the best clearance as far as I know and honestly every LT will dyno within a few horses of each other. So it's more a question of design, fitment, and quality of materials... (stainless vs coated vs uncoated)

Can anyone help recommend a setup for me given these parameters? This will be one of the first mods I make - if not the first. Thanks, in advance...

Don't forget about your intake as well.... Your motor can't spit out what it can't suck in... free flowing exhaust and free flowing intake go hand in hand A Lid and some free mods are an excellent place to start!

Hope this helps!

OH BTW, SLP Products are waaaaaaaaay overpriced, don't let their marketing get you all fuzzy inside, do research before just going with brand names! (no offense to SLP product owners or SLP themselves, it's just the truth... )

 

I've been through a few exhausts myself, including:

1. SLP dual/dual with CME tips
2. Electric cutout on the above
3. 12" Dynomax bullet before cutout with above
4. Kooks LTs, catted-y pipe with all of the above
5. Kooks LTs, catted-y, and Hooker with CME tips

And finally, my car is at Speed Inc. getting their over the axle true dual exhaust with ATR Pitbull mufflers and no cats, also with the CME tips. Of the above exhausts, I've really liked the Kooks setup with a Dynomax into the cutout, but the drone was awful. The Hooker is a nice setup, but it is very quiet at cruise, and just kinda barks at WOT. It wasn't really what I was going for either.

Do yourself a favor. Find local people with different kinds of exhausts, and listen to them from the outside and in. No matter what people will tell you on the Internet, every exhaust sounds different in person (as compared to something like LS1Sounds.com, which is a GREAT site BTW). Find something you like IN PERSON, and go with it. That is the only way you won't be disappointed.

 

Dont ever go with the Flowmaster 80 series.

 

i cannot strees that enough...

 

correct

magnaflow rules. loud but not too loud, and agressive and relatively cheap.

 

Having a TD setup run over the axle to mate to your CME will be pretty expensive. Most people dump at the axle due to the extra cost.
Going over the axle, most people are running 2.5" TD's.

With some money and a good exhaust shop you can do anything. Good luck.

 

First off about the headers, I have Jet-Hot Lt's and have never seen another set of LT's that tuck up under the car better, besides hooker LT's( Jet-Hot headers are designed off the Hooker design with only small changes to make them install easier and stronger flanges). They were cake to put in.

For exhaust I have the TSP true dual system with x-pipe and 18inch dynomax bullets. The sound is incredible, but it is pretty loud, and I was amazed that the drone at highway speeds(70mph) is actually quieter than my old cutout. acceleration at slow speeds causing some rattling of the interior which can easily be fixed.

Sounds to me like what you are looking for is Hooker LT's or Jet-Hot Lt's, with a hooker or Jet-Hot y-pipe and a hooker cat-back. I have heard this setup in person, and I think it is the best sounding of the cat-backs. Good luck.

 

Meentss02, what kind of deal did speed inc give you on the td setup? im thinking about doing the same thing

 

If you'll look on their website, it is actually more than what they are showing. With before and after dynos, don't expect to walk out of there for under $1500, and I'm providing new tips for them to work with. I'm also using custom clamps. I'll get some pics up if I ever get my car back...they ran into a snag and haven't started on it yet.

That price includes all mandrel bends, 3" to the x-pipe (custom) and 2.5" after over the axle and out the back. Most of the price is tied up in labor...they told me it takes every bit of 2.5 days to get this done, including painting the finished product (which will be black on my car).

 

i love the sound of my system. if it had rear exit tips, it probably wouldnt sound as loud on the inside. its only loud on the inside when getting up to speed when regularly driving, but once your cruising, its nice and mellow. sounds rediculously good when revved though

if you lower your car, i would go with a 2.5" true dual system, then stay 2.5 all the way over (or under) the axle. under axle is going to be cheaper, but you sacrifice a little clearance. after hearing my system, there is no way i would go with a y-pipe setup. if you have a custom 2.5" system put in, you will probably be able to supply them with the cats and x-pipe, then have them fabricate the rest.

tell them to remove the tunnel brace, flip the fuellines and their brackets up, and beat in the driverside support under the car, all for extra clearance.

 

Not to take away anything from your setup. I'm sure it sounds awesome.

BUT,
I wouldn't discount Y-pipe setups. I went from 3" True duals X-pipe dumped at the axle (sounded killer) to a QTP Y-pipe and SLP 2OTL catback and I actually prefer the the sound of the catback over the sound of the TD's.

It's all subjective.

 

Does the one muffler in the cat-back systems flow well enough to support a decision to go with LT's OR would the muffler become a bottleneck once the stock manifolds were replaced with headers?

If you were to rank the potential bottlenecks in the stock components, what would that look like (worst-first)? 1. Cats 2. muffler 3. manifold ??? Or is there a bend in there that worse than any of those?

 

The biggest bottleneck on a completely stock exhaust is the muffler then the manifolds.

 

You said, remove the tunnel brace? You mean take it off and leave it off, this doesn't affect any support or stiffness of the body? I could tuck my duals up a lot more with that thing out of the way. But I thought it was there for support.

 

Take that flimsy strip of metal off and bend it. You'll see how much "stiffness" it provides.

 

Yes, that piece was more of a GM afterthought...what they were thinking at the time I will never know.

 

Yeah I bent it a little putting my exhaust on, but had never heard of anyone just removing it.