MPG improvement via rear spoiler and or fins?
01-24-2019, 07:50 PM
#1
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2008 E350
MPG improvement via rear spoiler and or fins?
Hello everyone! I have a 2008 E350 in SF Bay Area and normally get 18mpg combined freeway city driving with a light foot, which is pathetic. After running into an article about rear spoilers or fins being able to improve MPG on certain cars (link here), and looking into small trunks spoilers such as this one on amazon (
) Has anyone noticed any MPG improvement from installing small fins or a spoiler on their w211?
Thanks!
Thanks!
01-25-2019, 08:33 AM
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1922 Ford Model T / no OBD
Aerodynamics are very tricky and there is no mathematical formula that can be applied.
That is why designers spend huge money for tunels so they can check their ideas in real wind.
Typical sample - driving pickup with tailgate down. All logic would say that should improve mpg, yet MythBusters did tests on Chevy and gate down lowered mpg. The wind turbulence behind the cabin increased with tailgate down and that was the factor.
But that doesn't mean tailgate down on Ford might not increase mpg as different cabin produce different turbulence.
I add trunk wing on my W212. The car makes 30-45 mpg depends on driving conditions and if the wing changed anything in aerodynamics, it is not measurable.
seems it keeps rear cleaner in the rain, but that might be subjective.
That is why designers spend huge money for tunels so they can check their ideas in real wind.
Typical sample - driving pickup with tailgate down. All logic would say that should improve mpg, yet MythBusters did tests on Chevy and gate down lowered mpg. The wind turbulence behind the cabin increased with tailgate down and that was the factor.
But that doesn't mean tailgate down on Ford might not increase mpg as different cabin produce different turbulence.
I add trunk wing on my W212. The car makes 30-45 mpg depends on driving conditions and if the wing changed anything in aerodynamics, it is not measurable.
seems it keeps rear cleaner in the rain, but that might be subjective.
01-25-2019, 10:35 AM
#5
Hello everyone! I have a 2008 E350 in SF Bay Area and normally get 18mpg combined freeway city driving with a light foot, which is pathetic. After running into an article about rear spoilers or fins being able to improve MPG on certain cars (link here), and looking into small trunks spoilers such as this one on amazon (link) Has anyone noticed any MPG improvement from installing small fins or a spoiler on their w211?
Thanks!
Thanks!
01-25-2019, 10:41 PM
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2008 E350 4Matic, 2011 E350 4matic
If anything, I would think a spoiler would make gas mileage worse not better. At high speeds, the surface area can act like a wing and provide lift to the car. That would be bad for handling though so that's the point of a spoiler, it spoils the air so you can get more traction on the ground and better handling. They use it on airplanes so you can decrease speed when coming in for a landing.
