Making the Ioniq slippier

[aerohead]

Originally Posted by freebeard

aerohead -- That's fine, man.

For the angle of the not-spoiler, look to that Mercedes Benz concept with the retractable boxed cavity.


https://i.imgur.com/W8TA6tA.jpeg

edit:
Whoops! I guess it's this Toyota patent from 2016


http://www.autoguide.com/auto-news/2...-car-tail.html

The next door neighbor had an extensible, nested pickup bedcover, similar to your tail.
Some would find the aesthetic off-putting, but the air would 'like' it.

[Phase]

Originally Posted by aerohead

Quite the torture chamber!
An interesting challenge.
1) Any existing holes can become anchor points by sandwiching oversized fender washers on each side of the hole, captured there when the fastener is snugged.
2) Heat-wrap would help contain the infrared.
3) Extra heat-shields with air-gaps.
4) Partial perforation of panels nearest the heat source if necessary.
5) Forward narrow panel, all-metal.
6) One-piece behind, to the rear suspension lower arms.
7) The lower arms themselves could carry their own 'moving' belly panels.
8) Behind those, a single-piece panel with diffuser.
9) Urethane-rubber floor mat material to close gaps.
Just thinking out loud.

geez that sounds expensive. im trying to go the cheapest route

[Phase]

any idea why the ioniq 6 coming out would add that random spoiler halfway down the back? why not just let the air flow stay attached? wouldnt it be more aero to keep it smooth?

[Drifter]

Very 1980s...

https://www.youtube.com/watch?v=WATe_ea1RRY

Toyota upped the ante with the addition something of a Kammback-ish sun shade:

[Phase]

so for the coast down testing, pretty much i find a spot and go up to say, 70 mph, then put in neutral and just ride the car till it stops, and mark the spot? then do the same thing with the aero mod attached and see if my range increased?

because doing that 2 hours of driving nonstop testing for the side mirrors was a pain, stressful, difficult with traffic, and a waste of 5 dollar a gallon gas...

[Drifter]

Originally Posted by Phase

so for the coast down testing, pretty much i find a spot and go up to say, 70 mph, then put in neutral and just ride the car till it stops, and mark the spot? then do the same thing with the aero mod attached and see if my range increased?

Yeah pretty much. I would put out a cone or something to mark where you want to start coasting. Then drive up to it with your cruise control set at whatever speed. Cancel cruise & coast in neutral as you pass the cone. Rolling to a stop is ideal, but you might also be able to roll to another landmark and note the speed.

Then circle back and do it again. Use the "resume" function on your cruise control to try and use the exact same starting speed. I'd probably do 3 tests unmodified and 3 tests with the modification. That should be enough to show whether the change provided a large improvement.

You might also see about using an OBD2 logger to log your speed. That would probably be best because you could compare the speed vs time curves to see if any random bump or gust of wind suddenly changed the slope of the curve on one run...

[freebeard]

Rolling to a stop is ideal, but you might also be able to roll to another landmark and note the speed.

25-0 would take maybe half the total time required. A constant uphill incline might speed things up.

[Phase]

Originally Posted by freebeard

25-0 would take maybe half the total time required. A constant uphill incline might speed things up.

Rolling to a stop takes forever with the new gen 2 Ecopia 422 plus tires overinflated 5 psi

Hard part is going to have to find an empty road where I won’t disrupt traffic

[Drifter]

Originally Posted by freebeard

25-0 would take maybe half the total time required. A constant uphill incline might speed things up.

I suspect you'd have to be extremely diligent to discern small aero changes with a 25mph coast down test since rolling resistance would be the primary force working against you at those speeds.

Your end on an uphill idea is a good one if you wanted to do quick & dirty A B A testing. Using flat ground (and averaging runs in both directions) would be better if you wanted to take your speed vs time/distance data and try to calculate your car's coefficient of rolling resistance & CdA in a spreadsheet.

[Phase]

Originally Posted by Drifter

I suspect you'd have to be extremely diligent to discern small aero changes with a 25mph coast down test since rolling resistance would be the primary force working against you at those speeds.

Your end on an uphill idea is a good one if you wanted to do quick & dirty A B A testing. Using flat ground (and averaging runs in both directions) would be better if you wanted to take your speed vs time/distance data and try to calculate your car's coefficient of rolling resistance & CdA in a spreadsheet.

Here’s a random idea, tell me if it’s flawed,

Say I find two markers or objects, like street signs or light poles or whatever they are maybe a quarter mile apart?

I drive to 70 miles per hour, and when I get ti the first check point, put it in neutral and start a timer. Then measure how many seconds it took to get to the second check point. Do it a few times for an average.

Then put on the aero mod, and do the same exact test, and if it took less time to reach the check point, even by 2-3 seconds, that clearly means the aero mod is working right?

Or is that test idea bad?