i have an 07 with a 550 h.p. frpp whipple supercharger. i have 1 3/4" kooks LT with 3" catted h pipe and 08 bullitt axlebacks. it's a manual and it's been dyno'd on a mustang dyno at 456 rwhp and 439 torque. my ford racing procal tune before the headers and h pipe was 469 rwhp and 442 torque. i do race it at the strip with my best at 11.96@ 119.5 mph. i like the sound but it is alittle too quiet. do i cut the cats out and make it an off road h pipe with the bullitts or leave it with the cats and which axlebacks would sound the best with this set-up?

 

I have pypes muffler delete and I think they sound really good. The only thing is, when you install them, the fit is picky, really have to work with it to get it exact...

 

im running an O/R h pipe and SLP loudmouth right now and its crazy loud. actually looking to get some flowmasters to quiet it down a little.

 

My top favorites are...

Pypes Violators

Pypes Muffler Delete

SLP Loudmouth

And straight pipes with American Thunder axle backs

 

i had the gta's with the kooks and didnt sound good. there is a guy locally selling flows, maybe those.i was thinking jba's?

 

Are you running Kooks cats with a supercharger? Man I would cut that sh*t out ASAP. Several threads about those cats clogging and tossing the motor. JDM told me to cut out my cats or they would clog/fail within 6 months.

 

yes i am still running the cats. they have been on there for 14 months or abot 6000 miles. there are getting cut out soon.

 

Get a catless X or H pipe and then just run some straight through mufflers like those SLP's, Borla Stingers, or magnapacks. Should be plenty loud. I found that the chambered magnaflows were a bit too quiet.

I listened to every exhaust video i could find on these GT's....

I just ordered some magnapacks last week. Right now its way too loud in the cabin with catless H pipe and 3" glass packs, that dump onto ground before rear axle. I chose the 3" magnapack cat-back (16674) because it has a nice deep tone at idle and gets loud when you get on it. Originally wanted flowmaster american thunder cat-back, but the sound is way too raspy and high pitched for me. Doesnt have the clean deep sound for the v8 that I like.

I would've bought the straight Bassani axle back race mufflers, http://www.stage3motorsports.com/pro...-Mufflers.html
Similar to the magnapacks but even a little deeper and smoother. But I wanted 3" all the way back and these are only 2.5" so that was my problem

 

i might cut the cats out and use the bullitt axlebacks. there is no drone with those. i actually lost low end torque with the 1 3/4" longtubes. i hope i wont lose more cutting the cats out.

 

Glad to hear it. Let us know how it turns out. Getting the exhaust tone just right is a long journey with this 3v motor.