Rear diffuser?

[Phase]

Best way for my rear diffuser to work will probably just be by making a super smooth full underbody. Heck I wonder how much drag would be reduced just by flat panneling that whole underside canyon with the cat convert and exhaust.

[IRONICK]

If I were you, I would also cover the engine frame with aluminum sheet.

[Phase]

Originally Posted by IRONICK

If I were you, I would also cover the engine frame with aluminum sheet.

Is that the area where the front axel is?

[IRONICK]

yes

[aerohead]

Originally Posted by Phase

Best way for my rear diffuser to work will probably just be by making a super smooth full underbody. Heck I wonder how much drag would be reduced just by flat panneling that whole underside canyon with the cat convert and exhaust.

On the Audi 100-III it was good for delta Cd 0.010. ( Cd 0.23 if the Hyundai responded the same )
Filling in the rest, with the sub-3-degree diffuser, on the Audi was good for another delta-Cd 0.020 ( Cd 0.21 perhaps for IONIQ )
Your skirts get you to your target of Cd 0.20.

[Phase]

Originally Posted by aerohead

On the Audi 100-III it was good for delta Cd 0.010. ( Cd 0.23 if the Hyundai responded the same )
Filling in the rest, with the sub-3-degree diffuser, on the Audi was good for another delta-Cd 0.020 ( Cd 0.21 perhaps for IONIQ )
Your skirts get you to your target of Cd 0.20.

I officially have the passenger side mirror removed permanently and using abs plastic with weather stripping so it looks really flush. Drivers side mirror comes on and off depending on car washes and city driving versus long highway trips and so on

2 extra mpg happens with 1 cd drop. I def need to clean up the bottom front under tray and the whole middle shaft

[freebeard]

1 cd drop

0.1 Cd or 0.01 CD? One point drop?

[Phase]

Originally Posted by freebeard

0.1 Cd or 0.01 CD? One point drop?

0.01

According to all of the calculators online that gives my car about a 2mpg boost give or take

My gfs Corolla hybrid is still out performing my Ioniq on the highway for some reason even after my aero mode. No idea why. I wonder if it could be do to her car having a super smooth under body while mine is a bit messier and damaged.

[aerohead]

Originally Posted by Phase

I officially have the passenger side mirror removed permanently and using abs plastic with weather stripping so it looks really flush. Drivers side mirror comes on and off depending on car washes and city driving versus long highway trips and so on

2 extra mpg happens with 1 cd drop. I def need to clean up the bottom front under tray and the whole middle shaft

I think the 'calculators' are a bit 'liberal.'
I gave you all the numbers for your car.
Removing one mirror would drop you about Cd 0.0075, or, Cd 0.2325 ( delta- 3.12% ).
No way you'd see mpg from that as reported.
just sayin'.

[Phase]

Originally Posted by aerohead

I think the 'calculators' are a bit 'liberal.'
I gave you all the numbers for your car.
Removing one mirror would drop you about Cd 0.0075, or, Cd 0.2325 ( delta- 3.12% ).
No way you'd see mpg from that as reported.
just sayin'.

I’m not saying I have a 2mpg boost from one mirror removed. It’s probably like 1 to 1 and a half mpg. I’m saying it seems like 2 mpg is gained when cd is dropped 0.01

When my passenger mirror is removed, I can definitely feel less air resistance and use less throttle when driving. When both are removed, I can feel an even bigger difference. With the wheel skirts, I can also feel a difference in how the car move thru air.

I when I said I did the rest diffuser test and it made the car feel more grippy and like it’s being tugged, I guess I was right with how it felt since the next week when I tried to do the testing at higher speed, the diffuser ripped in half because air was getting underneath it

So hopefully with a smoother underbody or wheel flarings and behind the wheel boat tailing, I can actually feel a physical difference and improvement when driving like the mirror and wheel skirt mods

I don’t know if my mind is playing tricks on me or not though, but it seems like these mods so far only help at the lower highway speeds at like 65 mpg. I see an improvement there. But when I’m going 80-90, my mpg is practically the same. Not even 1 mpg higher…