exhaust and MPG

I'm sure this has been asked many times..but I could not find the answer, have a new to me 11, thinking of cat back magna flow, has anybody seen a MPG improvement with exhaust upgrade or just better sound ? thanks Rob

In most cases the claimed gain in MPG by any manufacturer is negated by the driver's right foot. Most drivers love the throaty sound of a CAT back system so they accelerate harder to hear it.
Generally any system is designed for a performance gain not MPG.
To improve your MPG you need to drive it like an old geezer and be very light on the accelerator and brakes. It also helps to avoid long periods of idling and stop and go traffic as well as higher speeds since the AV has the aerodynamics of a brick. It helps to keep stock ride height and tires (properly inflated)instead of a lift and oversize tires too.
You may get some MPG increase with an economy tune and proper maintenance.

I'll second what Vaeagleav said. I got no noticeable mileage from my exhaust. There was maybe a little more power. Once I added the Headers and a proper tune the power went up a lot but I can never keep my foot out of it enough to show a mileage gain. LOL click the Charlotte link in my signature and you'll understand.

Did a cat back system on my '95 Jimmy. Saw zero change.

I bought a used 2000 Jetta diesel to improve my Avalanche mileage.

mikeyjm1 said:

click the Charlotte link in my signature and you'll understand.

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Nice. So what what your lap speed? Top speed?

AirJunky said:

Nice. So what what your lap speed? Top speed?

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I've done 110 on the back straight but, that was just the Black Fridays laps. You can't see it there but, there are a ton of other people out there I just got clear for a few minutes.

mikeyjm1 said:

I've done 110 on the back straight but, that was just the Black Fridays laps. You can't see it there but, there are a ton of other people out there I just got clear for a few minutes.

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