Aftermarket exhaust and mpg...
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From: Vancouver, BC
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Wondering, since gas prices seem to be climbing daily! If this is a mod I should consider...
Would adding an aftermarket exhaust (2 mufflers, xpipe, no resonators) increase gas milage, drop gas milage or remain same?
Would adding an aftermarket exhaust (2 mufflers, xpipe, no resonators) increase gas milage, drop gas milage or remain same?
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From: Thousand Oaks, California
My Ride: 2008 550i Jet Black on Black Leather, SAT with Paddles, Logic 7, Comfort Seats, NAV, Sport Package, PDC, Xenons, Sirius, Trinity 12W LED Angel Eyes, RPi GT Exhaust, M rear spoiler, ACS Roof Spoiler, Tinted Tail Lights, Bimmian Carbon Fiber Pillar Trim, Bimmian Shadow 550i emblem, RPi Scoop, E60 Forum Cling, Mtec bulbs in fog lights, Mtec 2W LED for License Plate Light Bulbs, K&N Filter, Bimmian LED Smoked Side Markers, Blackout roundels, Carbon Fiber Kidney Grills.
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Originally Posted by tbal' post='596440' date='Jun 5 2008, 01:40 PM
Wondering, since gas prices seem to be climbing daily! If this is a mod I should consider...
Would adding an aftermarket exhaust (2 mufflers, xpipe, no resonators) increase gas mileage, drop gas mileage or remain same?
Would adding an aftermarket exhaust (2 mufflers, xpipe, no resonators) increase gas mileage, drop gas mileage or remain same?
Of course this also implies that you will "Keep Your Foot Out of it" which is not an easy thing to do with a GREAT sounding exhaust on the car!! 
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Originally Posted by flyingpuck' post='596445' date='Jun 5 2008, 03:46 PM
Theoretically, your mileage should increase!There is less back pressure, so your engine SHOULD work more easily, therefore more mileage! Of course this also implies that you will "Keep Your Foot Out of it" which is not an easy thing to do with a GREAT sounding exhaust on the car!!
Of course this also implies that you will "Keep Your Foot Out of it" which is not an easy thing to do with a GREAT sounding exhaust on the car!! +1
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From: Atlanta Burbs
My Ride: 08 550 Carbon Sport Almost everything factory, but no sound upgrades.
You may like the sound but I doubt the fuel saving would pay for the new exhuast system. Do the math.
If you improved one mpg (v 25mpg) that is 4% or 16 cents on a 4.00 gallon.
Now take the cost of the new system and divide by .16. That will give you the break even gallons to use to cover the cost of the new system.
I don't have the foggiest the cost of your exhaust system, but you may be looking at 100,000 miles to break even.
I will gladly welcome corrections to my math.
If you improved one mpg (v 25mpg) that is 4% or 16 cents on a 4.00 gallon.
Now take the cost of the new system and divide by .16. That will give you the break even gallons to use to cover the cost of the new system.
I don't have the foggiest the cost of your exhaust system, but you may be looking at 100,000 miles to break even.
I will gladly welcome corrections to my math.
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From: San Jose, CA
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Shouldn't. You could convert to E85, www.mye85kit.com, for $395, which would help the conversion. The ECU will correct for the higher octane (it will advance the timing) and you'll get better performance.
If there's a greater than .60 cent delta between premium and E85 (provided you get ~20 MPG), you save money, including the worse mileage you'll see from the less efficient E85 fuel. Your injectors will run cleaner (in fact, the alcohol will clean them).
If there's a greater than .60 cent delta between premium and E85 (provided you get ~20 MPG), you save money, including the worse mileage you'll see from the less efficient E85 fuel. Your injectors will run cleaner (in fact, the alcohol will clean them).
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From: Vancouver, BC
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im happy with just gasoline lol...
sooo, basically, exhaust or no exhaust, i would remain in the same ballpark correct?
Just seems that on my other vehicle, once i added an exhaust, the mpg dropped dramtically...?? could be a mental thing i suppose.
sooo, basically, exhaust or no exhaust, i would remain in the same ballpark correct?
Just seems that on my other vehicle, once i added an exhaust, the mpg dropped dramtically...?? could be a mental thing i suppose.