I seen claims that it does but want some answers from those that have put a system on and if you had any inprovemt of gas mileage over that stock system. Because of the sky high gas prices I am thinking of putting one on my truck but just don't know if its worth it or not. The truck is a 2000 F150 with the 4.6 V8 auto trany that has a little over 94k on it.

 

yea it does, i put a y pipe with twin pipes out the back, with no muffler, i gained bout a mile or two to the gal. and it sounds great, if u want more fuel milage try one of those turbonators and a new air filter and whatnot that will also help and its cheeper

 

Exhaust systems help as long as you dont have a lead foot he he . Also the "turbonater doesnt work or tb spacers.

 

if you're going to suggest the "turbonator" or any other hoaxes, you might want to let them know that you're truly kidding.

 

I would buy a air filter(1 to 2 mpg) or get a tuner.

 

I guess with my lead foot I would loose gas mileage if I put a system on the truck.

 

I just bought my first F150 I have always owned 250's I like the truck alot but it was to quiet didn't clatter like the diesel. I had a magnaflow with dual pipes comming off the back it sounds great. Now I hope it will get better mileage. It just turned over 500 miles hope this helps. GREAT WEB SITE

 

Yes they do if you don't drive your truck like a sports car.

 

I put an Air intake on mine and got about a mile and a half, now I am think about exhaust. Do you think it will go up even higher or is my truck spent?

As for the turbonator, everyone jokes about it, but has anyone actually tried it????

 

Ditto. I just installed a mac intake on my 4.2L F150. That along with the si/do exhaust with 2-1/4" dual pipes out back has given me better milage. I don't know how much because I haven't calculated it yet. but I don't have to mash the gas as much to keep up speed than before. That tells me right there I'm getting better mpg's. And the gas gauge seems to be agreeing with me. But you only get better mpg's if you keep your foot out of it as much as possible. That's hard to do with a newly installed performance mod though.

 

That is the kind of answer i was looking for.

 

SI/DO slow down exhaust gas velocity.... thus reducting your performance... if u wan true dual use an X pipe if u wan a y pipe keep it singled after the Y pipe.