lincoln ls exhaust and mpgs question

[djknowledge]

i recently got a set of magnaflow mufflers with a magnaflow x pipe installed and a resonator delete. previous owner had the car running with a couple of coils misfiring. i am not sure but a couple of people have told me that it could have damaged my cat. i even got a comment on youtube sayin my cat was messed up on youtube. if i replace it with one of the magnaflow high flow cats, would that improve the overall sound and exhaust flow on my car? also ive noticed i barely get 11 mpgs while other ls owners claim at least 17 or better. im replacing the fuel filter soon and gettin a k&n intake along with the new cat, so witht that done,does anyone know if this would improve the mpgs? thanks in advance . ps this is the video of my exhaust, and i still have rev limiter on so....YouTube - lincoln ls exhaust

 

[Outkast]

if you are getting 11 mpg, and your not driving like a total douche, then yes, somthing is wrong.

 

[Ls208]

yea thast pretty low, the lowest ive ever seen mine go is 13 or 14 and thats just because i was driving stop and go traffic for like 4 months straight.

 

[djknowledge]

drivin habits

no i would like to believe i dont drive like a douche as the roads around here are horrible, and all there is to drive through is stop and go traffic, i use 93 octane or wuteva super is at exxon, and i do oil changes every 3 months, along with a gumout fuel system cleaning, to no improvement. i have a brand new air filter, all new spark plugs and coil packs, and i barely ever go over 3000 rpms. any suggestions?

 

[djknowledge]

anyone?

 

[LS4me]

A clogged cat will kill your economy.

 

[owlman]

I can believe 11 if it's really all stop-n-go traffic

 

[mep32jep]

change your fuel filter and put in some complete fuel system cleaner in your tank. Made a huge difference in mine

 

[Silver_LS]

Its sounds okay to me, I have magnaflow exaust. If that is a 03+ LS which I think it is from the cutouts in the bumper, your never going to get the rev limiter off...