Making the Ioniq slippier

[Phase]

planning on doing a lot of willamette valley mpg testing at various speeds tuesday as i do a gold panning trip to south oregon. will update on that.

and did another drive around tonight with the cardboard diffuser. def changes how the car feels, sounds and handles. i can '' feel'' the downforce, but i cant tell if there's an mpg gain or not. will try later this week on wed or thursday to do an a-b mpg highway test late at night with and without the diffuser

[aerohead]

Laid awake thinking about his San Diego to Florida trek.
Some thoughts:
* 50-mph minimizes the magnitude of heat flux the cooling system must handle. It's conceivable that the lower radiator shutters never opened, minimizing main body drag.
* 50- mph also minimizes 'windage' ( ventilation drag of rotating wheels ).
* 50-mpg minimizes rolling resistance, as it varies arithmetically with speed.
* At 50-mph, any crosswind or gust effects would be minimized.
* At an 'average' 50-mph, ascending grades might be undertaken at 45-mph ( the legal minimum ), minimizing climbing losses ( an old trick of the Mobil Economy Run ). [ An inclinometer in the cabin would inform how speed was chosen ].
* At 81.1% regenerative kinetic energy recovery, one might allow a gravity-assist 'overspeed' on downhills,, which not only increases wheel power for harvesting, it also 'boosts' hill-climbing on the next grade.
* Choosing 'mild' temperatures allows AC 'OFF', windows-up driving, saving on accessory losses.
* Curve resistance is less at 50-mph.
* Vehicles overtaking the 'slow' vehicle may impart a degree of thrust as they pass.
* Tires inflated to maximum sidewall rating?
* Choosing a more conservative acceleration rate than the EPA's Mobile Testing is constrained to use would reduce power demand for all accelerations.
* Opportunity drafting might avail itself ( some trucking companies use telemetered speed governing which the driver cannot defeat ) [ As long as your 'average' speed is 50-mph, you can claim it.
-----------------------------------------------------------------------------------
Hybrid assist and regen makes it near-impossible to parse out what's going on in a hybrid. Emission Analytics testing indicates that 'hybrid' adds 48% to mpg. 80-mpg would become 54-mpg without it.

[Phase]

Originally Posted by aerohead

Laid awake thinking about his San Diego to Florida trek.
Some thoughts:
* 50-mph minimizes the magnitude of heat flux the cooling system must handle. It's conceivable that the lower radiator shutters never opened, minimizing main body drag.
* 50- mph also minimizes 'windage' ( ventilation drag of rotating wheels ).
* 50-mpg minimizes rolling resistance, as it varies arithmetically with speed.
* At 50-mph, any crosswind or gust effects would be minimized.
* At an 'average' 50-mph, ascending grades might be undertaken at 45-mph ( the legal minimum ), minimizing climbing losses ( an old trick of the Mobil Economy Run ). [ An inclinometer in the cabin would inform how speed was chosen ].
* At 81.1% regenerative kinetic energy recovery, one might allow a gravity-assist 'overspeed' on downhills,, which not only increases wheel power for harvesting, it also 'boosts' hill-climbing on the next grade.
* Choosing 'mild' temperatures allows AC 'OFF', windows-up driving, saving on accessory losses.
* Curve resistance is less at 50-mph.
* Vehicles overtaking the 'slow' vehicle may impart a degree of thrust as they pass.
* Tires inflated to maximum sidewall rating?
* Choosing a more conservative acceleration rate than the EPA's Mobile Testing is constrained to use would reduce power demand for all accelerations.
* Opportunity drafting might avail itself ( some trucking companies use telemetered speed governing which the driver cannot defeat ) [ As long as your 'average' speed is 50-mph, you can claim it.
-----------------------------------------------------------------------------------
Hybrid assist and regen makes it near-impossible to parse out what's going on in a hybrid. Emission Analytics testing indicates that 'hybrid' adds 48% to mpg. 80-mpg would become 54-mpg without it.

He claimed he could have gotten better numbers if he had chosen different routes and tried to hypermiling. Said he didn’t even try to get good mpg. Just drove straight. That was his main trip

Don’t forget his “ steady state” numbers that he tested a few months later with a different Ioniq. It was like 83 mpg at 50mph. 74 mpg at 55 and 67 mpg at 60 and 61 mpg at 65 mph

Like I said I’ll report back if I can get some testing done tomorrow

I think the reason why the mpg drops big time at higher speeds in the Ioniq, say 80-90 mph, is because the car can barely switch to ev mode and use its hybrid features. The load is too high so it’s constantly using the engine. Reducing the load with aero mods would skyrocket the mpg, not just slightly improve it. That’s my theory based on tail wind if my car lines up with them at high speeds

[aerohead]

Yep!
Aero power requirement is changing with the cube of the velocity.
At 90-mph aero horsepower is 28.9.
At 50-mph it's 4.9.

[Phase]

so far the tests are still planned for tomorrow. will probably do the 65 mph test first as traffic will be flowing more aggressively exiting the portland metro. dont want to impede flow. then i will drop down to 60, then 55 as i get between woodburn and salem and then salem and corvallis. the least busy stretch will probably be between corvallis and eugene, at which i can get in the right lane and do CC at 50 mph...

forecast is showing about 3 mph tail wind, so that may slightly boost the numbers, or maybe itll just help compensate for having to slow down or accelerating for merging traffic or minor passing. either way it wont hurt the numbers. also should be in the mid to high 60s for temps, so i wont have to run the ac either which will be nice

[Phase]

70 degrees outside. No wind. Had to drive with flashers on at the lower speeds. The numbers are fluctuates because of how the hybrid system works. So worse numbers versus best numbers at the end of the 20-30 mile runs with the car switching between ev and engine mode.


65 Mph- 63-67 mpg

60 mph- 70-75 mpg

55 mph - 76-79 mpg

50 mph - 86-94 mpg. Insane but truckers did not like it!

My aero moss clearly beat Wayne’s numbers!

[Phase]

Mpg dropped significantly when coming back on the drop. Driving between 75-80 mph fluctuation into a 3-5 mph mild headwind put my mpg between 48-51 mpg. Huge drop

[Phase]

City driving is also giving great mpg results. 64-68 mpg with tons of red lights and max speed limit of 45. Using mild hypermiling techniques. Car is rated at 57 city. So lower drag is still making a diff at the city speeds too!

[aerohead]

Originally Posted by Phase

City driving is also giving great mpg results. 64-68 mpg with tons of red lights and max speed limit of 45. Using mild hypermiling techniques. Car is rated at 57 city. So lower drag is still making a diff at the city speeds too!

Excellent! Something virtually zero automotive journalists have grasped so far!
Why lose available wheel power to aero drag or rolling resistance, when you can capture 81.1% of it and shove it back into the pack?
The legacy carmakers have essentially, completely missed the boat on this.
And why their range 'sucks' compared to the more streamlined offerings of the competition.

[Phase]

Originally Posted by aerohead

Excellent! Something virtually zero automotive journalists have grasped so far!
Why lose available wheel power to aero drag or rolling resistance, when you can capture 81.1% of it and shove it back into the pack?
The legacy carmakers have essentially, completely missed the boat on this.
And why their range 'sucks' compared to the more streamlined offerings of the competition.

The wheel covers definitely get attention and comments at the gas pumps or places I park with people asking about them lol


Still the big issue to tackle is the 80mph fuel efficiency. I’m extremely satisfied with city and back country farm road driving and mpg. Wide open interstate at 80 though, very depressing. Better than most others on the road, but I Desire more