How much of a difference would putting a true dual exhast on my 04 hemi make (gas mileage, HP)?

 

big ZERO for both, might even drop cuz it will lose back pressure and take more gas to get it moving. Kinda like shooting a spit-wad through a 1/2 inch diameter pipe.

 

The big exhaust gains come from changing the exhaust manifolds from what I've read. The couple guys I know who switched to true duals have been disappointed in the loss of low end and no mileage improvements. Kinda sucks.

 

The Tech at my dealer pretty much said the same thing, Loss of backpressure and drop in response. All for what a little more rumble when you punch it, I passed.

 

Don't do it...everyone is correct. You WILL have a very noticible loss of low end HP and TQ. Also, I went through several different "loud, straight thru mufflers" that did the same thing. I finally found that going with a Flowmaster 70 series, 3" in, dual 2 1/2 out (cat back)..gave me the sound and performance without any power loss at all...excellent low cab noise as well. I think some guy on here has a link for the Flowmaster 70 sound..check it out.

 

Here is the links to my 70's. Exact setup as Sliders.

www.geocities.com/dheath_1999/ram.wma
or
www.geocities.com/dheath_1999/ram.mp3

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