which exaust gives the most milage in return?

 

The one used mainly downhill?

With a tailwind?

seriously though,

What do you mean mileage in return? MPG or longevity? None will do it all, unfortunately, and there are so many factors to consider..noise levels, legality for emmisions, whats on the intake side..etc.

Honestly in my not so vast aftermarket experience, the best I've done so far was a cat-back setup from Jardine. The cost was better than the big names, the fit was better than average, the looks were disappointing, (but that wasn't what I was after), but quality was good..sounded great. But I also did a Granatelli MAF, cold air intake, and a bored out throttle body, so by itself, I have no idea what it would have done. As a package, it was a whole new experience to drive..HUGE difference. But it all added up to about 1500 bucks, too..

If you want looks that last, find a stainless system from one of the big names, it'll still flow better than stock, and sound pretty cool.. But your wallet will feel it, and you probably won't ever see a return on your investment in MPG.

For my money? I just picked up a pristine 93 F350 4X4 Crew cab, 460, all bone stock, and I'm going with a high flow cat, and a single 3" through a muffler yet to be decided, but I'm leaning towards a Flowmaster Force II..catback set up for my truck is just over 200 bucks at Summit..

Thats my 2 cents..

My bad, I said Jardine up there.. it was a Mac system...

 

I spent the $ after looking at all other systems. I went with the Gale Banks Engineering complete stainless system. It cost, but is awesome. The workmanship is incredible, and power, above say 3000 rpm, under full load (15,000" goose trailer) is unbelievable. If you don't run loaded, I'm not sure you would appreciate the phenominal increase in breathing

 

Put the standard exhaust back into the truck, Frankly, I'm very tired of people asking us how to get better mileage out of a pick-up truck. Too many of you are spending too much money trying to get an extra 1/2 mile per gallon. Please compare the money and time you put out, to what you actually get in return..
There is no pick-up truck that has great mileage, the trucks are heavy and have good engines designed to drag a payload of 1500 lbs or more. A pick-up is for hauling..if you ain't hauling buy a Small car.

I apologize for smashing your hopes in advance.