For the people that have added flowmasters except for the 50HD have you noticed any decrease in fuel mileage or performance?

 

When I put the Flowmaster system on my '06 the mileage went down but that was cause I womped on it more cause it sounded so good!! When I took it easy the mileage was about the same, maybe a tad higher.

Bill

 

I added a 40 series 2 chamber and my performance went down. im not sure about the mpg. The reason my performance went down is because I installed a 2.5 inch muffler and the stock size pipe is 3.0 inch. . I hear that the hemi likes the flo through type muffler instead of a chambered muffler. im no expert, I just read stuff.

 

I'm running a Flowmaster 40 on my 2009 Sport. Just like Bill, I've seen a drop in MPG, but that's just because I can't keep my foot out of it.

 

same here except i have a big horn

 

I added a flowmaster 40, and less restrictive Y-pipe. Sounds Great!!! There was a noticeable increase in power. When I drive "normal" the mileage is about the same, but like everyone else, I use more gas cause I love the sound of my truck.

 

I thought that on the sport the factory muffler was 3" SI / 2 1/2" DO. Is this incorrect?

 

I have an SLT and when I bought it it was a single exhaust. I bought the dual exhaust bumper and borla exhaust after I installed the flowmaster. The flowmaster was an old muffler I had sitting around. I dont know the factory exhaust size, I thought it was 2 1/4.

 

Thanks for your reply. I just want to upgrade the factory sport ehaust but I don't want to loose performance, I don't mind if it stays the same. I love the sound of the Flowmaster 40 but I have heard unless you go with the 50HD. Does any one know if the magnaflow 14 sounds similar to the flowmaster 40?

 

I had a 3'' Gibson installed (single swept side) and it sounded great, did not lose any power, in fact I gained some. I later installed a Magnaflo dual chamber 3'' in dual 2.5 out swept side and had a noticeable power loss down low but mid range to top end was increased. If I had to do it again I would stay with the 3'' all the way through.