Which of the Flowmaster cat-backs is better for sound/performance: the Force II or the American Thunder? Are they both 3 inch all the way back? I have a 3 inch cat. Also, I have noticed that these cat-backs have the single outlet mufflers. Can I put a Flowmaster 3" offset inlet/2.5" dual outlet muffler on the system, or will it not fit? Any help would be much appreciated. Thanks.

There all going to be about the same in performance. Sound is a little diff. Most people seem to go for the Crossflow muffler. Hope this helps some!

I have the 3inch with 2.5 outlets and I love it.

Typically the systems with a single muffler with a single-in, single-out are a little more for performance. The exhaust goes in and right out the other side, where as the systems with dual outlets on each side of the car change the direction of the exhaust thus slowing its exit from the car down. I dont know how much of a proven difference there is however. I full three inch with three inch outlets on each side of the car, but i wanted the dual exhaust look, with my slow car i didnt think it it would really matter.

did that make any sense?

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305 TPI
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