Question about improving miles per kilowatt
 

Been lurking on the forums for a while looking at all the mods people have done to their EVs to get more range and wanted to ask a couple of questions.

I have an EV that has a slit on the side that I assume is an air curtain for the front wheels, does it matter if the air is directed directly into the wheel rather than around the rim?

Does decreasing rim size affect milage by a lot? Currently have michelin primacy tour a/s tires and I'm wondering if swapping them out for other tires with lower rolling resistance can help with adding more range?

I've been looking at youtube videos left and right from this forum and others about aerodynamics and such but I don't think I'll have the ability to make much easy modifications to my car that wouldn't void warranty. Just want to see if I can get just a little more range out of my EV. I also know driving slow and being very gentle on the peddle helps, I am more worried about long distance driving because that's where I actually need the range and I usually use cruise control at the speed limit. Want to see if I can increase my range by 10% with some optimizations and maybe some better tires.

'improving'
 

The more we know about your car, and 'how' you'll be driving it, the better we can consider possible options.
There will be a crossover speed at which aerodynamics will come to dominate the road load the motor and battery will be required to overcome.
Motor and transmission efficiency is, for all intents and purposes, fixed.
All you've got is rolling resistance and aero to work with.
The lowest rolling resistance is your friend, as you're thinking.
Your driving speed will tell us something about aero.

It's the genesis gv60 performance edition and I seldom drive it across the state to see my in laws. I usually drive between 65 - 70 mph on the highway. I just need a good 15 - 20 miles extra range at that speed in order to make it to the in laws on one charge, I want to avoid the electrify america's horrible charging infrastructure if possible X)

It's generally the load-rating on the tyre that will limit your choice.

I wonder if those tires from hankook (ion) are any good vs the current ones I have. They mention in the promo they are made for EVs and have low rolling resistance.

What is the length of your parking space?

Maybe about 200 inches or 16.6 feet

Being gentle on the pedal doesn't matter. Lower overall speed is key.

Twenty inches isn't enough for a boat tail. but you might find success with a perforated base plate or box cavity.

I think the first thing I'd try is covering those huge open wheels, or at least tuft testing the body behind the wheels. And then maybe adding some separation edges at the rear. How smooth is the underbody? I'd like to see a tuft test of that rear window. Looks like about a 20° slope?

https://www.genesisofbrooklyn.com/in...g-color=FFFFFF

The Advanced Edition has 20" wheels instead of your 21" wheels and has a bit more range. I'm not sure if that's the only reason, but it probably helps.

The Performance edition also has larger 2nd motors (quite heavy) and some additional hardware that adds a bit of weight but yea I thought the same when I first saw the tire size difference.

Give yourself more time to get there, take backroads that you can drive slower on, maybe that will help.

Here's a good video on the underside, look up on youtube the video "What's underneath my Genesis GV60" by Car Spec Garage (I don't have enough posts to put links)

Any recommendations for caps to cover the wheels? Been looking around but can't find anything for my car.

I'm looking at this option as well but I do think some small tweaks to aero and tires might get me there. (Yes I know buying tires for the sake of range is expensive).

Except for acceleration and hill climbing, steady state weight isn't a really huge bugaboo as aero drag. Hardening your current tires with more airpressure might give you the extra range as driving 5mph slower or some sort of drafting.

Used to be here: changing the loose nut attachment to the steering wheel is a primary fix

I load my leaf up with 500lb of wood pellets and it barely has a noticeable effect on range. Weight is almost irrelevant.

Live in florida, we have flat land here :)

Good to hear, sounds like aero and my tires are the only options along with driving slower.

I can only recommend Michellen energy saver A/S and Bridgestone ecopia.

Are either of them quiet at all?

That's really smooth underneath! Not much you can do there. Pizza pans are often used as wheel covers! :D

But how do you attach them? Any transparent options so I can still see my rims?

ecomodder.com/forum/showthread.php/dzus-fastened-moon-disc-wheel-covers

http://www.mooneyesusa.com/v/vspfile...MD11-DZ-2T.jpg

Transparent covers would collect dirt and debris on the inside.

You could fabricate a disk that fit between the hub and wheel of either clear stuff or painted black metal. Inmho, people also need to show they benbow calipers.

Isn't as aero as on the outside but does stop air leakage through the rim.

add 10% range
 

So, in order to stretch the battery 10%, you've got to do what you're already doing with 90% of the energy.
A 10% reduction in Road Load.
All aero.
All R-R.
Or, some combination of the two.
--------------------------------------------------------------------------
The KIA EV6 GT-Line RWD is EPA COMB 310-miles range, compared to the IONIQ 5, at 256-miles.
The RWD has 235/55 R19 101H KUMHO Crugen HP71 EV ( M+S ), vs 255/45 R20 105V Michelin Primacy Tour A/S ( M+S ).
The narrower section has better aerodynamics, and I suspect a lower coefficient of power absorption.
Mercedes-Benz is using a 185mm section on their EQXX, range leading concept.
--------------------------------------------------------------------------
In 2018, Robert Palin, at electrek.com, reported that the 19-inch Tesla Model 3 Aero Wheels were good for a 10% efficiency gain, and 5% higher range on the highway.
Since Hyundai/KIA/ Genesis all share the same mechanicals under the skin, you might be able to find a direct fit wheel, or wheel cover option, which along with a LRR tire, nearly gets you to your 10% range target.
If not, a small amount of streamlining ought to get you into the inzone.

Yeah, but he does like the looks of the present probably very expensive rims. Otherwise your comment about efficiency was spot on

No doubt I love the rims but I still haven't seen anyone make aftermarket rim covers for my car yet :( still looking at the possibility of changing rims for smaller wheels (19" the smallest) but if I can keep using mu current 21" rims that would be preferable. I also looked around for those hancook ion tires but they aren't in stocks anywhere yet. They seem to offer low rolling resistance and better range for EVs so I wonder if they are any better than the current Michelin primacy tour tires I have on atm.

You're not going to save 10% on wheel treatments. There's no getting around the fact that you're going to have to slow down.

The good news is that saving 10% doesn't require going all that much slower. My guess would be something like 4 MPH slower. It's the "mod" that improves all drag producing parts of the vehicle.

Here's the various mods for consideration. None except the extreme ones are going to get you 10%.
https://ecomodder.com/forum/fuel-eco...ifications.php

'tour' tires
 

Not too many years ago there was about a 132-page special report on rolling resistance published online.
All-season LRR radials had the lowest drag.
Followed by 'touring' tires which had more.
And bringing up the rear were the 'performance' tires with the highest drag.
In a just world, California would have been able to require full disclosure by tire makers of specific rolling force coefficients for each make sold in the state. It would have helped the entire world.
Having not passed into law we're left with the equivalent of buying a home of known square-footage, however no disclosure requirement of whether or not there's any insulation in the walls or attic.
Shame.

Yea I'm upset about there not being easily published specs on tires.

wheel covers
 

I've no idea what the cost was, but on an episode of 'Rick's Restorations', a local Las Vegas, Nevada sign company created high density foam tooling using AUTO-CAD-CAM, used to vacuum-form heated polycarbonate sheet material over, creating a clear structure, much like poly skylights are formed.
It would be interesting to know what Lexan covers like this would fetch.
The Mercedes' EQXX concept wheels are completely 'sealed' like this would be.

Clamp it under a perfect 19[-21]" circle and inflate it with compressed air. Trim to fit.

At 70mph most of your battery energy is going to pushing around air. There are two ways to help reduce that effect.

1. Drive slower.
2. Change the shape of the vehicle like this guy: https://www.aerocivic.com/

Well, I guess there's a third option. Sell the crossover and get something more aerodynamic like a sedan or an Aptera.

Tires might help some. But will it be enough?

Not gonna sell, love this car and yes I'll drive slower to compensate but when I do get my hands on those hancook ion tires and the wheel covers ill do some testing and report if there are any range gains. Do you think a front air dam would help? Not sure considering the bottom of the car appears to already be pretty smooth.

A front air dam might help slightly. Or it could hinder slightly. It mainly helps vehicles without a smooth underside.

Although the 65+ Efficiendy Mods list puts a front air dam at a moderate increase in better mileage, so that's encouraging.
https://ecomodder.com/forum/fuel-eco...ifications.php

New tires generally get worse economy. You want really worn out ones if you want good economy. That's a separate discussion from buying efficient ones to begin with.

I doubt an air dam would help since EVs in particular are designed with smooth airflow in mind. My guess is it would make things slightly worse.

The rear of any vehicle is where most of the aerodynamic drag can be helped. People like boxy rear ends, so manufactures don't go all out aerodynamic on the rear. But if you did it yourself you could get a major improvement in range, much more than with eco tires and front air dam combined.

https://media.wired.com/photos/59336...l-metro-02.jpg

As said, air dams are a band-aid. At the very least provide a central notch to provide a high speed jet that will pull air from behind the wheels.

A splitter won't impede the approach angle (as much) and provides 'free' downforce.

Any examples of this notch?