Okay so I have a full custom exhaust on my Mustang with 2 Flowmaster Super 40's with dumps on the back of them. They are both 2.5" offset entrance and offset exit. Well I recently got another flowmaster super 40 catback kit with tailpipes as a gift. So when I put the catback on my mustang, I'm going to take the two dumped flowmasters along with my 05 FX4 to an exhaust shop to get true dual with no cats. My question is will two 2.5" mufflers be too free flowing for the truck causing me to kill the low end torque? I'm not going to buy new mufflers right now. I'm just going to use what I have. Should I have him run 2.25" pipe all the way back and just enlarge it for the entrance and then reduce it at the exitsof the mufflers back to 2.25" for the rest of the way to the bumper? I'm alo going to put tips on it, but that makes no difference. I just don't want to kill my torque. I also don't want to restrict it too much either.

Doug

 

well with the flowmasters your gunna lose tq but i have true duel with two flowmasters and lowend tq is my only complaint. it sounds great and if its free id say why not? you can allways change them later. ill get a sound clip for ya im a min. i would also get a X pipe it helps out alot with proformace

http://vids.myspace.com/index.cfm?fu...ideoID=9717328

 

awesome video polpilot thanks for sharein'

 

if you will never plan on supercharging it go 2.25" for maximum lowend tq retention-phil

 

2.25 with an X-pipe and you shouldn't notice any loss in low end torque, but you won't gain any either. Well with the "Slo"masters you might notice some even with the X-pipe, Magnaflow would be the way to go for optimum power.

 

I ran a SIDO 2.5" Flowmaster 40 system on my F-150 with no cats, and that thing ran great. Doo it!

 

since your going catless dont forget to get a set of O2 sims