Does Adding A Roof Box To Your EV Kill Your Range? (Featuring Our 2023 VW iD.4 Pro S RWD)

[@MephistophelesSK]

Man, third video, third thumps up! I've heard about the theory a backward roof box is more efficient... Thanks a lot for testing it! As an european, I think in kwh (or liters) per 100km and not in miles per kwh (or gallons). I want to share my calcluation, maybe some european will think its helpfull: Without roof box (3.9 kWh / mi) -> 100km / (1.6mi x 3.9 kWh / mi) = 16,025 kWh/100km Roof Box forward (3.4 kWh / mi) -> 100km / (1.6mi x 3.4 kWh / mi) = 18,38 kWh/100km Roof Box backward (3.3 kWh / mi) -> 100km / (1.6mi x 3.3 kWh / mi) = 18,93 kWh/100km Greetings from Germany 😊

[@BlakeCheck]

Man I’m glad this was at least a little helpful for someone! Haha

[@MephistophelesSK]

@@BlakeCheck Yes, I see... by far not your most popular video on your channel. But I like such technical details. :-)

[@yiyangcheng]

It was nice meeting you at the recent EV show talking about the difference of the 21 and 23 ID4!

[@BlakeCheck]

Pleasure chatting with you. Let me know how things turn out for your iD.4!

[@23ID.]

I don’t know how to fold the mirrors on my 23 Pro S. Do you by any chance know how to?

[@BlakeCheck]

I think only the Plus trims get auto folding mirrors. You can manually fold them inward on the pro s just by pushing em in but that’s it. Pretty lame.

[@23ID.]

@@BlakeCheck Yeah that is pretty lame for a $50k car.

[@chibangomgs5409]

Drivers side door. There should be a section with Windowbuttons. You'll also find a round toggle . This sets the sidemirrors. Position, heating and folding​@BlakeCheck turn the toggle and it will change what parameters to adjust

[@23ID.]

@@chibangomgs5409 Doesn’t work for Pro S 2023+ I believe.

[@BlakeCheck]

@23ID. Yeah just the top trim ones I think. I forgot what they’re called.

[@TheJoseph4871]

Never thought about turning the box around. I have the weather tech bag for my luggage, and I can not turn backwards because if it rains the water might leak inside. That is per the instructions. Also my miles per kilowatt was the same as your test #2. I have to remember my speed because in Chicago you don’t have posted speeds of 70. So mine was a little less.

[@BlakeCheck]

Thanks for watching. I thought about doing a bag. Have you noticed any draw backs from it. Noise, damage to the roof, damage to items inside?

[@EPeltzer]

This is a great consideration and question to answer. However mostly one would use such a roof box on long trips on the highway, so probably averaging much higher speed like 75mph. Air drag increases as the SQUARE of speed. Basically I would think that the loss of efficiency would be quite a bit worse than you found at under 50mph. You might average say 3.6 kWh per mi at 75 with no box, but only do say 2.8 with the box. Maybe less, who knows. A roof box can really screw up aerodynamics. Also the size of a box is a big variable. You probably want to avoid the really big wide ones and go with long narrow ones. It's mostly frontal area that causes the drag. Thanks for bothering with this test though good work.

[@BlakeCheck]

Thanks for your insight and thank you for watching. Maybe I’ll do a highway only test at some point.