I’ve been doing more than one thing to try and improve the car’s range. The easy way would be to just by more cells, but I like a challenge. One of the many ways you can improve any car’s fuel efficiency (while increasing its power and raising its top speed) is by reducing two things - its rolling resistance and its drag coefficient. Rolling resistance is already very low in this car because the engine can spin freely when coasting and the tyres are Nitrogen-filled, low-rolling-resistance tyres inflated to a slightly higher than usual pressure. I still have a few ideas of ways I can reduce the car’s rolling resistance, but for now I’ve been focusing on the car’s drag coefficient.
The car was manufactured and was first road-registered by Blade Electric Vehicles, but the donor body was a 2010/2011 Hyundai Getz bought straight from Hyundai before it had been registered. Legally speaking it’s a standalone vehicle that shares a lot of its parts with a Getz, but mechanically speaking it’s a conversion of an existing vehicle. The later model Getz already has a pretty good aerodynamic profile but there’s a few areas that can be improved on almost any car, and a big one is the wheels.
Fun fact - the wheels themselves are responsible for anywhere between 5-30% of a compact car’s aerodynamic drag, creating huge amounts of turbulence that disrupts the laminar flow around the vehicle! Hubcaps aren’t always just aesthetic, some of them are designed to optimise aerodynamics. The problem is, aside from aesthetic hubcaps where “optimal” is just what’s currently in fashion, the real-world “optimal” design is a trade-off between optimising for aerodynamics with a perfectly flat surface and interrupting the airflow to redirect some of it towards the brakes. If the brakes don’t have air flowing over them, they’ll overheat and won’t work as well. No one would want their brakes to stop working, thus hubcaps have air holes. Also, unless your car has mirror-image hubcaps on the left & right sides, they’ve prioritised aesthetics at least a little over aerodynamics.
However, the main way of braking in this vehicle is the regenerative braking. This can capture up to ~16kW of power from the wheels to put back into the batteries. The brakes aren’t used much, except for when you need to stop quickly or to keep the vehicle from slowly rolling at traffic lights. The brakes may not get too hot with sealed hubcaps… But there’s only one way to find out! Tape up the wheels, drive it hard for a few days and see how it goes.
Clear tape so it looks less obvious and less like a rundown rust bucket when I’m driving around normally.
Results from this experiment - the brake pads are fine and even sealed up like this, they’re still way cooler than the average car’s brake pads. Time to make it permanent and more aesthetic!
Back in the 50s & 60s, cars frequently had what are called “Moon wheels”. These are basically solid, chrome mirror-finished hubcaps, often with ripples or other accents, sometimes covering the whole wheel but frequently covering only a small area in the middle (“baby moons”). Cars in the 50s & 60s also used drum brakes which were much more prone to overheating than today’s disc brakes. Guess what frequently happened back then.
I wasn’t a fan of the retro polished mirror finish, but I liked the idea of someone else doing the machining for me. A few emails later, I had arranged an order for some epoxy-coated brushed metal press-on hubs at a size to match the EV’s tyres. Stainless Steel ones like this are easier & cheaper to obtain but I wanted spun Aluminium to keep the wheel weight as low as possible. Which I find extra amusing, given my affinity for Stainless Steel with my DeLorean. 
I may be biased, but I think these look absolutely gorgeous.
And when the light hits them juuust right, they light up like a Silmaril.
Fitting them took me a few weeks to fit them all make sure everything was right. Pro tip - use foam tape to pad out the hub (especially the wheel balance weight) or else it’ll make a clicking noise as the hub wobbles & contacts the wheel balance weight, particularly at high speed. Geek Shirt #28 was me fitting these hubs, posing with a sword because they look a little like Captain America shields. I don’t know why. It’s not like Captain America uses a sword or anything but it seemed like a good idea at the time.
Hubs all replaced
I think they look totally scifi.
I drove around the roads near HSBNE and monitored how many amps were needed to maintain travel at certain speeds, and I also monitored the energy consumption for daily driving over repeatable routes. End result: around 4%-6% more range, depending on how fast I’m driving. Just by swapping the hubcaps! Totally worth it. 