Delta wing riser.

[rallytaff]

Anyone else running this notice that your gas mileage improves? Mine has got better going from around 23.9 to around 24.5. That's city and some fast fwy driving. Just curious.

 

[WannabeST]

Are you sure this is an effect from the wing?
It it possible that the wing is now at around 5-7 degrees of angle of attack. At that angle most diffuser or small aero devices make the best downforce to drag ratios. So it is possible the wing is now more effective in the drag department. but in all honesty, I would lean more towards this being a slight change in throttle input.

 

[Dialcaliper]

I have it installed, but haven’t noticed any improvement. Part of that may be because I just subconsciously assumed it would make economy worse due to the increase in frontal area.

0.5mpg is not a lot and could easily be related to something like temperature as well.

But it’s good to hear similar gas mileage numbers - I’ve been getting around 24 with short commutes and 29-30 on road trips. The 200TW tires don’t exactly help things in that department (I noticed a loss of several mpg after switching from more standard summer tires.

 

[rallytaff]

Could it be that the slightly raised slots allow more air to pass through as opposed to the normal wing? Who knows?

 

[rallytaff]

Are you sure this is an effect from the wing?
It it possible that the wing is now at around 5-7 degrees of angle of attack. At that angle most diffuser or small aero devices make the best downforce to drag ratios. So it is possible the wing is now more effective in the drag department. but in all honesty, I would lean more towards this being a slight change in throttle input.

Throttle input hasn't changed. I still drive it the same way.

 

[WannabeST]

Throttle input hasn't changed. I still drive it the same way.

Did you compare the same road to the same road, or check throttle input? because the change is very minimal. If you watch your active mpg it takes very small % in throttle input to change the mpg by 0.5 mpg (I can check later on my drive home). I just suspect that it's either a placebo, better throttle use, better weather, maybe some maintenance was done? more psi in tires? Because the wing being raised would actually be making a touch of downforce and downforce is drag. So it should hurt mpg instead of improving it, but again it is possible this setup produces less drag than the standard wing and the turbulent air hits the hatch.

 

[WannabeST]

Could it be that the slightly raised slots allow more air to pass through as opposed to the normal wing? Who knows?

This is possible, I don't think it's likely. Because the air going under would get scooped up by the wing like a GT wing makes downforce. I think it is a possibility this setup produces less drag than factory and is using the air more efficiently. I'm sure someone smarter than me in this forum can confirm.

 

[rallytaff]

I drive all over the place, in the city and on the fwys. I just keep and eye on the gas mileage and saw that it had increased slightly.