Can anyone tell me the performance gains if any with a tru dual set up compared to a flowmaster sido, particular gas mileage and low end performance on the 2006 5.4 FX4.

 

i bought the truck with sido flow master straight out the back with 3.5 tips... now i have true dual with an H pipe and glass (short) with 3.5 tips out the corners... higher rpm power increases slightly with true... bottom end pretty much stayed the same... gas mileage... same... tone.. alot better (but my flowmaster was rusty and fell apart about 10k after i bought it ha. personally just go for what u like sound wise. the differance for me was slight... i do have colant cold air intake, superchips too.

 

the Y pipe collector is the most restrictive part of the factory exuast. So anything you can do to get rid of it, you will see a gain.

Best set up there is, X pipe-twin SISO- Dumped or direct side exit (dont have pipe going over axle)

-Patrick

 

Good technical info.

 

i agree everything else is more personal preference.a true dual 2.5'' will give you more horsepower,and could lose some bottom end.a new y-pipe and single 3'' into a si do would work fine unless you want all out horsepower.