Would a Flowmaster 50 Series SUV muffler on stock pipes in a 2000 Expedition improve the mileage at all? how loud are they? thanks.

 

I am probly comparing two different vehicles. I put Flowmasters on my 97 f-150 4x4 4.6l it sounds better, but no increase in feul mileage.

 

Interesting, how about performance?

 

I put a flowmaster 50 on my 4.6 in a 98 f150 4x4 along with cat back exhaust and k&n air filter....sounds like old muscle car!!!! Increased milage and performance alittle....about 18 to 19 on highway if going around 70.....I heard prformance is more noticable in the 5.4....Hope this helps.....My opinion just do it because of the sound. Muffler and pipes and stainless tips were 300 bucks.!!!!!

 

Thanks for the info. I'm not that interested in sound. This is a family car, not a show car. I'm interested in results. If there are significant economy and/or performance gains to be had then the cost may be worth it. But I don't really care to spend the money on slight gains in economy and performane so I can get a cool sound. No offense. The change in exhaust would occur when the current system needs replacing. Seems like many people buy these exhaust systems for their sounds, since there is much talk about the sound. Does anyone know the criteria used by Ford engineers to design the exhaust? Is it just get the cheapest thing we can find, or is there more? How much more does it cost to make a well performing muffler than a cheap poor performing muffler? The same equipment is use to make both, right? Is it expensive to spend a little more time on the flow calculations? Sometimes I wonder why OEM parts are many times consider junk, and must be upgraded. Does anyone have any REAL insite into these design considerations? I'm talking about aftermarket parts that do not change the emissions. Obviously if Ford could eliminate Govt imposed constraints the system would be different. I can also see where designing a better head would require more engineering and testing, but for an exhaust system I wonder how much more effort a better flowing system requires. Hmmm, did I make a short story long?