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Aftermarket Bumper Aerodynamics Questions!

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Old 09-10-2014 | 07:51 PM
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Default Aftermarket Bumper Aerodynamics Questions!

Hey all, yeah noob here clearly. Got a question regarding aftermarket bumpers and aerodynamics that may translate to MPG's, yeah I dint buy a prius I know. Im really into all the stubby , shorter, smaller bumpers like PS Brawler, EVO, etc..these obviously leave the wheels and wheel wells opened a lot, will this slow you down and give you worst MPG, over say a full almost stock size aftermarket bumper, or no difference?
Thanks! Genrec
Old 09-10-2014 | 07:59 PM
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I really think there wouldn't be much of a difference in aerodynamic when comparing stock to any aftermarket bumper

Now weight would play more of part then aerodynamics
Old 09-10-2014 | 08:02 PM
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Originally Posted by jaker t5
I really think there wouldn't be much of a difference in aerodynamic when comparing stock to any aftermarket bumper Now weight would play more of part then aerodynamics
Co sign... We drive giant heavy bricks, aerodynamics won't make a difference unless your new bumper has two canoes on either side that lean on the windshield.

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Old 09-10-2014 | 08:35 PM
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I don't even know how to respond to this one. You drive a brick, on solid axles, unless you best abumper that rins to the ground to create a negative pressure under the chassis, and a scoop to channel air over the hood (think airplane like) you aren't going to see anything different. Maybe 1-2 mpg loss. Maybe......

My mpg went from 17 avg to 14 avg with a stubby, 3" lift, 35" trail grapplers. I have a 2012, auto with 4:10's.

Does that help?
Old 09-10-2014 | 08:56 PM
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Cool guys..just wondering really..I have 2014 JKU Sport just picked up, getting 20+ mpg stock, mostly hwy driving...goal is 35's on 2.5 of lift with some armor, just kind of wondering about this before deciding on which armor.
Old 09-10-2014 | 08:58 PM
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Originally Posted by genrec
Cool guys..just wondering really..I have 2014 JKU Sport just picked up, getting 20+ mpg stock, mostly hwy driving...goal is 35's on 2.5 of lift with some armor, just kind of wondering about this before deciding on which armor.
the lift and tires will hurt your mpg more than a bumper. I actually didn't see a difference in mpg after my bumper install. Lift & tires were on for about a year before the bumper.
Old 09-11-2014 | 08:48 AM
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I was getting 18.5-19 with my 14 jku with 3.73 I added 2.5" lift (netted 3 front 2.75 rear) and this rock hard bumper. It dropped me down to 16.6-17.3 then again that was added 120lbs to the front.
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Old 09-11-2014 | 09:04 AM
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Mine went up from 17 to 23. My bumper has a stinger. The stinger actually generates lift, therefore reducing friction on my tires and improving mpg. It also cuts into the air causing it to have a smoother break over my Jeep. I don't have exact numbers, but I estimate my drag coefficient decreased to .30. Pretty solid when considering a Prius is .26.
Old 09-11-2014 | 09:36 AM
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as long as you get a front splitter you should be good. I think those are special order though but don't quote me on that
Old 09-11-2014 | 09:37 AM
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Originally Posted by Invest2m4
Mine went up from 17 to 23. My bumper has a stinger. The stinger actually generates lift, therefore reducing friction on my tires and improving mpg. It also cuts into the air causing it to have a smoother break over my Jeep. I don't have exact numbers, but I estimate my drag coefficient decreased to .30. Pretty solid when considering a Prius is .26.



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