SLP

We finished our prototype cat-back exhaust system for the GTO. Here are the basics:

Now - more importantly, this is just the prototype . Parts will not be ready for shipment until summer. We need to receive the raw materials and build the production systems, which will take some time. Please be patient as we hustle to bring these products to market - I can promise they are worth the wait

Best regards -
Brian

TriShield

granitemonkey

BIGBOS

Looks good

Shinkaze

Looks good and Loud

demonspeed

iTrader: (7)

Looks nice... unlike purple paint

Miguelius

I don't see the sense in replacing the stock exhaust, which sounds magnificent, is plenty loud, and probably does not restrict the power of the engine significantly. As we all know, Pontiac and Holden engineers spent hundreds of hours tuning the exhaust to get it just right. This sounds like replacing the exhaust simply for the sake of replacement. I doubt that you will gain any significant horsepower, at the expense of having a cruder sound. But, as we said in the Sixties, do your thing . . .

PendragonZ

Wow, someone signed up just to reply to that.

Got any sound clips of the exhaust? I think the GTO could sound
a little bit better. Stock is great, but some people don't like to sound
like everyone else.

demonspeed

iTrader: (7)

They also like to sound a lot louder.

SLP

Well, I too have heard GM and Holden spend hundreds of hours developing a muffler . I also read that they modeled and tested hundreds of mufflers . I thought, wow, maybe we can learn something here. As fast as we could, we cut open one of these ultra-special mufflers to see what the result was.

Fellas, I think we've been duped by the marketing group at GM.

The inside of the muffler is the most basic design possible, hardly something worth bragging about, let alone even admitting to have consumed hundreds of hours of engineering and testing. A perforated tube surrounded by insulation . The aftermarket has used this technology for 50 some years . See attached photo.

unit213

Where's that damned owned sign at...

Oh, here it is. GM has been

Joe "Preachers Sheets" DIESO

iTrader: (4)

Why even post on www.ls1tech.com where people need 800 rwhp daily drivers.

gto_in_nc

I think this is actually wonderful news for people like me who would like a smoother exit(LT headers, cats, mufflers, true dual, etc.) without losing the characteristic soundtrack that GM put together. Gimme an easier-breathing bolt-in stainless steel exhaust that has the basso profundo and burble of the stock exhaust without significantly increasing the volume (and making it slightly quieter would actually be preferable to me) and I'll be very likely to buy it...

grooves12

Well, I remember all the articles I read saying that GM did a lot of testing and tuning of the exhaust to get the SOUND right, not necessarrilly performance. But, the post-cat exhaust on this vehicle is probably one of the best systems GM has used in many years. TRUE duals, and free-flowing mufflers. I don't think those SLP pictures did anything to show that GM's muffler design is in any way inferior... in fact I think it proved that it is a pretty good design to begin with.

Let's see some cutaways of those SLP mufflers... I bet they look exactly the same with the only difference being less sound deadening material. Although, the X-pipe could be a selling point for some, the REAL advantage you are getting with an aftermarket system is DECIBELS.

Miguelius

Thanks for watching my back, Grooves. Jeez, I question whether it's really worth messing with an already great sounding exhaust (love to blast through the tunnels with it--and try that Porsche Cayenne commercial thing with playing the exhaust over the cell phone), and some guys question my credentials as a card-carrying car freak. Hey, it's one thing to truly increase the power with real modifications--more power to you--but I just doubt that the effort (and money) is worth it with the exhaust. Now headers, that might be different . . .

mrgto

GM did the best they could within the limits of the US DOT. SLP really doesn't have to worry about it. That is 2 systems for the GTO I have seen. I need to hear them now.

SLP

I agree - it is great to see GM introduce an “aftermarket style” muffler as OE, nothing inferior here in my opinion - equally, nothing fancy or magical either. Indeed, the SLP power-flow mufflers are similar in design - only we use smaller, more frequent perf. holes and different materials. The stock system does perform well too, as expected by design. There is not much power to be gained over the stock cat-back, unlike like the f-bodies. Besides a modest power gain, some of the advantages or selling features of the SLP system are:

1 - 2.5", CNC Mandrel bent (over 2" and 2.25" stock)
2 - True transition X-pipe
3 - Entirely 304 stainless steel
4 - More aggressive / better sound
5 - Modular, interchangeable mufflers
6 - Stylish, adjustable, double-wall tips
7 - Does NOT hit the "mounts" under WOT, unlike the stock tailpipe
8 - Lifetime warrantee

Best regards -

DANSLS1GTO

So long as it will bolt up to the long tube stainless headers you are working feverishly on - - then it's all good. I can't see changing anything except when going to headers. And as far as header's go - it is as much a looks thing as anything else to me. The engine just doesn't look right with the stock manifold on there...
Dan

SLP

the good news is that the headers literally 'fall' in place - quick, 1 hr job!

SkateBmx

What is the point of those big metal drums then, the ones that the perforated tube with the insulation is in?