kissmyss03

iTrader: (1)

ok i dont have much knowledge on down pipes. when spring hits i will be putting my mods back on ( CAI, shift kit, HP tune, exhaust )

i would like to go with a downpipe. i want a louder exhaust tone and am wondering if i should get a high flow cat or no cat. if i go with a high flow will it improve performance and make exahust sound a lil louder or no? and what size should i get. isnt 3inch only good if you are supercharged? i want to keep my resinator on this time around so my exhaust doesnt get raspy like it is without it and thought maybe a high flow cat down pipe or no cat down pipe would make it louder without raspy. thanks guys.

Semper91-RS

High Flow Cats give 99% of the power, with about 80% of the sound of a catless system. The Hogan 3" downpipe seems to be the popular choice around here. Not that I know where to get it. If anyone can provide a link, I'd appreciate it.

kissmyss03

iTrader: (1)

does anyone have a exhaust system with a catless downpipe, and still has resinator and either stock mufflers or aftermarket? hows it sound?

Count of Monte Carlo

You got it at http://hoganperformance.com/

kissmyss03

iTrader: (1)

i cant click on the one without the cat

Semper91-RS

DP7S is the catted..

EmersonHart13

iTrader: (3)

www.wbodystore.com

I just ordered mine yesterday...

http://www.wbodystore.com/grandprix/...-v8-p-219.html

:-)

Taz34SS

iTrader: (2)

I did a video of both the stock OEM downpipe vs the Hogan with High flow cat. It does wait the car up,but not as much as if you got headers to go with the pipe.

IF you really want to wake it up, talk to Milzy and have him make you some headers.

Semper91-RS

Post said video?

jpstax

I've been thinking about removing my resinator to get a louder exhaust note and maybe recover the 3 HP the GM Performance Division guys lost by trying to make my '08 LaCrosse Super (LS4) quieter. Could you please describe what "raspy" sounds like? I wouldn't want the exhaust note to sound wierd or obnoxious.

M/T link describing what the GM Performance Division guys did: http://www.motortrend.com/roadtests/...r_first_drive/

Taz34SS

iTrader: (2)

Search for my topic on downpipes and you will find the clips

kissmyss03

iTrader: (1)

when u drive it cold or rev it, the exhaust crackles like crazy and sounds like a ricer

Taz34SS

iTrader: (2)

Are you talking about my clip??? If so, that was after I drove the car and came back home to get my camera.

Again, If you want that sound, you will need headers. Period.

Kazmaniac

3" is the accepted norm for LSx engines.

jpstax

A GM mechanic told me mufflers for all FWD (LS4) cars are "40 Series Delta" Flowmasters. I think he's right, because the exhaust note for my '08 Buick Super sounds almost identical to this sound clip, only softer:

http://www.flowmastermufflers.com/40_delta.html

Taz34SS

iTrader: (2)

Sorry, but the OEM mufflers part for our exhaust are not made by Flowmasters. The whole exhaust from the cat back is made 100% in Canada.

EmersonHart13

iTrader: (3)

Haha, 40s from the factory, your mechanic is dreaming!

jpstax

Why would he be dreaming? It says the Flowmaster 40 Series Delta Flow application is for late-model performance cars with dual exhaust. The GM Performance Division outsourced some parts for the LaX Super (Bilstein struts, Delphi steering gear, Bose radio, etc), so why not the mufflers? I wouldn't be at all surprised if Chevy and Pontiac's engineers did too for the Impala SS and Grand Prix GXP. Don't forget the Corvette Z06 and Caddy CTS-V use Brembo brakes.

jpstax

Here's a link to watch/hear what Flowmasters sound like on Pontiac GXP:

http://www.youtube.com/watch?v=7PIgEt2cwXY

However, it doesn't say which Flowmasters were installed. They sound a lot louder than my LaX Super's and the Impala SS I test drove. They could be the Super 40's, not the 40 Series Deltas.

EmersonHart13

iTrader: (3)

Because if they did we would know. Notice how when they outsource those parts they put the names all over as you listed above. Yes the Impala, Monte, and GP have the same parts. Do you see that anywhere on an official GM publication that these cars use 40s, no. Why? Because if they paid for the name they would use it to sell cars...

Trust me, it makes sense...

And comparing by sound, eh no...

Think about it, just because my neighbor and I sound the same on the phone doesn't mean we both get to bang my gf....