boiler

Hey Guys,

Getting ready in a few weeks to put an exhaust on my truck but my question is this: driving mostly flat county roads and highways (rural indiana) and driving pretty conserved, what kind of gains do you think I could expect from a full exhaust (I'm going with Flowmaster American Thunder) and additionally gains from an Edge tuner? I average about 15-16mi per gallon right now. Thanks

-Boiler

otto457

You'll get 15-16 mpg. A canned programmer with an intake isn't going to help much. Most cat back exhausts may add a little power but not mpgs, especially with a chambered/baffled muffler.

skizriz

I'm gonna guess 12-13 after you are done. With the sound of the exhaust and the feel of the Edge, you will definitely drop a few.

foxracer0345

to give your a factual awnser based on expiernce obviously the guys above did not have, i have a flowmaster super 44 system with 35s. i was averaging around 10.4 after i did the exhaust. i will tell you that the exhaust did not help with mpg. but when i bought my edge evolution tuner, i gained 3mpg

HighRoller

I m only 2 weeks into my test. But can tell you after just a cat back flowmaster 3" & a airraid intake I saw little if any difference, also did new plugs n fuel filter, flushed the tranny, and no change. Well it did sound alot better, and seemed to have some more zip, but that could just be a mod mind melt. Avg 14.5 when stock, after mods and not,hammer footing 14.6

So yesterday I finally got my xcal2 updated with 2 custom tunes. 87 mileage tune and a 93 performance tune. So far I am only about half way through my first tank on the 87 tune. Wow what a difference, I m doing my best not to hammer down and so far based on my 65m daily commute its looking like I may end up around 16mpg. I plan todo a few weeks on this tune to see what the true result is before switching to the 93 perf tune. More to come. . .

skizriz

A factual answer based on experience that we don't have??? Really??? You have had your Edge for a couple of hours now ???

If you consider the AVG MPG you saw on your screen for the few miles you have driven it "experience", then you will be pretty disappointed when you figure out your actual MPG.

foxracer0345

well lets put it like this. ive had my exhaust for a year. saw no increase in mpg. easy to assume and exhaust will not increase your mpg. when i bought my 35's i lost 2 mph. so that put me at 10. when i bought my edge and ran my instant mpg on my truck, i now have 12.7? so to say you will deff drop a few sounds like inexpiernce a little...? but reading through your profile you have these things, so you must be doing something wrong

otto457

As I said before, exhaust doesn't get you too far. You realized this yourself.
MPG gains with a programmer aren't 100%. There is always a chance to gain, but results vary greatly. Driving style dictates the mpg gains. In your case the programmer helped you only get back closer to stock mpg ratings, which means there's more at work here than just the programmer giving "gains". Gains are deviated from EPA ratings, not current ratings.
For the OP, he has an intake, which needs to be properly tuned for to maximize its potential.

skizriz

boiler

Thank you Otto, your post seems to be the most logical. Now here is what I am basing my logic from, and I'll mention I am a semester from graduating with a BS in mech. engineering from a pretty decent school you might decipher from my sn. (and saying that might throw up a dumb***** flag to some of you but whatever here we go)...

Driving exactly the same as prior to installation, I would expect, key word expect minor as in <1 mpg gains from the exhaust because it is removing the OEM bottled up unit. Now my plans for the tuner would be to drop my shift points by 400rpm on each gear which according to the Edge website, you can do. If I drop each gear by roughly that amount, yes it will be more sluggish because its shifting more quickly and staying in the lower RPMs where you have far less torque and hp but would produce substantial economy gains. I'm currently running factory tire/wheel setup but that will change eventually as well. I currently average about 14.5-15 but my 70m daily commute is 95% interstate. I have averaged 16.5 before but that was a tank traveling to home and back from school and was 60-70mph state highway. Anyway, that's my logic on the situation. I don't expect big gains from the exhaust, but I do expect variable gains from the tuner.