I have the Loudmouth along with the SLP LT Headers and Random Tech High-Flow cats. I had the car dynoed at SLP and w/o tuning it recorded 370 HP.

I personally like the Loudmouth, and the headers helped with the "dreaded drone".

 

Loudmouth is stainless steel, Rumbler isn't. Not a fair comparison.

 

i dont buy the fact that ur 99 SS put down 370 with only headers and exhaust....my car onpy puts down 381rwhp with tuning.....

 

it's possible he's not talking about rwhp?

that would bring his rwhp to approximately 315 at the wheels... which is more realistic.

 

I'm very happy with my LM!!. With a lid,filter and LM I shaved off .4 tenths and gained 3.5 MPH in the 1/4mi!! How many HP....not really shure, but I really don't care either....

 

Just got the Rumbler and 3.73 gears from 3.23. Sounds great, but the gears put the rpm up alittle on hwy. When you let off the gas, it wants, and sometimes does backfire alittle. I'm going to get pacesetter LT's w/ catted 3"y pipe. I'm also lowered now about 1.5",anybody know about the clearence w/ the LT?

 

Excuse me for not being more specific...370 at the flywheel

 

There is no way you shaved .4 and gained 3.5 from just a loudmouth catback. True gains for the LM should be about half that. My guess is the weather conditions were more favorable when you ran your car after LM install and caused the rest of the gains you saw. Cold weather can add .3 to your ET and add 2-3 mph to your trap. I myself ran 13.4 @ 104 during hot and humid weather. I ran again a month later during cold weather and got a 13.1 @ 106.97 with no mods being done, same track and same 60' time.

But I'm glad your happy with your setup. The LM is one of the best bang for the buck catbacks out there and definately sounds the best IMO with stock manifold & cats.

 

i just put in slp lt headers and loudmouth today and when i started it up... worth every penny! if you plan on lowering tho dont get the headers

 

Just have the resonator removed and replaced with a bullet or twister style muffler and yours would sound the same and be stainless.

Loudmouths sound too much like glasspacks for me to like them. Too raspy, and the drone is horrible with headers in an A4 car.

 

The LoudMouth is awesome on a lightly modded car. Unfortunately, when you ditch the cats and add headers it sounds like ***. I put in a DynoMax bullet and it still sounds good at idle and WOT, but everywhere else is weaksauce...