Flowmaster Or Magnaflow

[PODGE]

I have a stock 03 GT. If I change to Flowmaster or Magnaflow muffler can I expect better gas mileage. What about a C/B system?

 

[StngStr]

My average before the magnapacks and o/r X was 20.2 mpg. Since then (December), my average has dropped to 18.4 mpg. I'm sure it has more to do with my right foot and leaving it in a gear too low just so I can listen to the badass sound though!

 

[road rage]

Go with the magnaflow cat back. In my opinion flowmasters sound better on the 5.0. I had flows on my 00GT and took them off and put a mac cat back and it sounds so much better.

 

[01GT eibach]

You won't see an appreciable change in mpg with just a catback.

 

[68 & 00 GT]

/\ right but get the Magnaflow. see my sig for a video. You may only need the mufflers. No real reason to get the whole catback, unless you want the tips (which you can buy seperately) or the mandrel bent / larger diameter pipes that are really only usefull on power addrer applications from what I understand.

Magnaflow sounds soooo good. Get an off road X with it

 

[Hrspwrd]

I have a 99 GT and noticed a slight increase in gas mileage when I went with two chamber flows. All that changed of course by the many other mods but the 2 chamber flowmasters can even make a stock car with no other exhaust changes sound really nice.

 

[01GT eibach]

No real reason to get the whole catback, unless you want the tips (which you can buy seperately) or the mandrel bent / larger diameter pipes that are really only usefull on power addrer applications from what I understand.

The other thing the Magnaflow catback brings you is stainless steel (a significant factor, especially for our Mustang brothren in the salt-laden winter streets of the North East). My opinion on this is that by the time you bought the tips and mufflers, and paid the labor for putting it all together, it would likely be in the price ballpark of installing an integrated catback. And the catback offers the additional advantages ... as we already mentioned ... of being mandrel bent, larger diameter, and stainless steel. IMO, the only reasons to not do a catback is:
1) because you want some special mufflers that are not available in an integrated catback, or
2) you really want to save a few dollars by changing out only mufflers.

BTW, the 3.5 inch tips fit perfectly in the existing Mustang GT bumper cutouts -- FAR AND AWAY better looking than stock.

 

[jrc_03_gt]

get the flowmasters 40 series

 

[XTONKAX]

Sixes. Comes down to a sound preference. I like both sounds, but in my area, those who have switched have all gone with Flowmaster. Hence, I went Magnapack!

 

[jeff1414]

magnapacks.....

 

[DBMSTNG]

Magnaflow has less restriction. i prefer them over flowmaster. you can get the whole magnaflow cat back for $300.