Well i have a similar exhaust issue, see mine will gecome nice when warmed up good but heres the catch

it will only make niose below 3000 RPM its absically the opposite of every other exhaust, now this is my second one, just muffler both times and it will growl nice and deep but it will jsut die as the RPM's get higher NOBODY has given me a good answer even muffler houses and its driving me nuts any suggestions?

 

My Jeep does the same thing. When I installed my 3" exhaust upgrade on my 2000 JGC I went with a Pro-Flo straight thru muffler with a complete 3" system. At low speed it has a deep rumble, as the rpms go up it has a slight drone. At highway speeds (65-85mph) it gets quieter. I think it has to do with the larger volume of gases flowing through the system at higher speeds which quiet it down. Of course at launch time you will both hear it and get a nice rear view of where I put my Warpspeedperformance decal. Even with the AWD I get rubber.

Anyway...if you want more sound go with a dtm, we are changing my single exhaust to a muffler back dual (strictly for looks) next week. I don't think it will help the performance and I know the Flowmaster will quiet it down. If the place in Dallas can dyno an all wheel drive I may find out some real results.

Dallas Warpspeed