Showcase for Wheel Discs

[mpg_numbers_guy]

Originally Posted by Taylor95

Seems like that is a rare occurrence for most people with these covers. I'm still undecided of I want to do this on any of my vehicles. I'm thinking that performance rotors (the ones with holes) might mitigate the extra heat.

I was surprised that it did it too. It only happened on longer highway drives with cruise control. Everywhere else it was fine. Didn't have any brake drag or anything.

Not saying that it's guaranteed to happen, but it's a possible risk, that's all.

EDIT: Further clarification. On pizza delivery driving I use the brakes a decent amount, but they never heated up. On the highway even with cruise control I would think that I wouldn't have issues, but I did..

EDIT (again): Brakes were new as of that year as well.

[oldtamiyaphile]

I had lightly warped discs after about 5k miles running moondiscs, which I put down to the discs - mind you I was towing quite a lot. If your brakes are marginal or you punish them a bit you might run into issues.

[19bonestock88]

I’ve yet to warp my front rotors, though I’ll admit my wheel discs aren’t made perfectly, so they may allow some air behind them to cool the brakes... now, occasionally I do experience some fade when braking from high speeds (usually 90+) so if I ever were to race the car I’d have to ditch the front wheel covers or do some louvers in the disc

[Taylor95]

Originally Posted by oldtamiyaphile

I had lightly warped discs after about 5k miles running moondiscs, which I put down to the discs - mind you I was towing quite a lot. If your brakes are marginal or you punish them a bit you might run into issues.

What vehicle was this on? My subaru and jeep have more ground clearance than most vehicles, which I think would help with brake cooling.

[California98Civic]

Originally Posted by Vekke

First and second have 1mm thick aluminum plates that are just glued from behind.

How did you shape those plates that you glued in from behind. How did you shape those plate that you glued in from behind? It looks like there are compound curves involved, yet the surface of the metal seems very smooth and without wrinkles or dents.

[serialk11r]

A thought on leaving some venting for the brakes, obviously the outer part of the wheel is spinning fastest, but vented brake rotors are also throwing air outward against the rim, so if you blank off the center but leave a few slots around the rim, then brake air can still escape. If it's totally blanked off, it'll recirculate back through the rotors again which is no bueno.


I also noticed that new Porsches are coming with "air curtains" ahead of the front wheels just like BMWs have had for years, I wonder how effective they are at reducing drag from the wheels. Apparently the Land Rover Discovery lost something like 0.003 Cd thanks to them.

[Snax]

I can't imagine overheating would happen with vented discs functioning normally under light duty unless as cited before, the cruise control is engaging the brakes. Seems to me like that part would make for automatic disqualification as an efficient thing to use.

Vented discs do still circulate air however whether the outer wheel is covered or not. Where that air is coming from and how much may matter quite a bit though. I.e., it could crop up more significantly with grille blocking and belly pan work that significantly encloses the suspension area. Seems to me like a rare oddity, but something to watch for.

[Snax]

I can't find the link for it, but I did read a study where they compared variations on wheel discs, with one variant being a wide ring around the rim portion covering about half of the radius. This allowed ventilation nearer the lug nuts and was shown to be within a few percent of improvement as a completely solid disc over no disc.

[freebeard]

x2

The top and bottom of a spinning wheel disk cancel each other out, plus you can get to the lug nuts.

[Vman455]

Originally Posted by serialk11r

I also noticed that new Porsches are coming with "air curtains" ahead of the front wheels just like BMWs have had for years, I wonder how effective they are at reducing drag from the wheels.

Nearly every OEM is using front wheel air curtains today, and a few (Honda Clarity, Lexus LC500, Hyundai Veloster N) have rear air curtains as well. The only manufacturer I can think of that doesn't have any models with air curtains is Fiat Chrysler--but their whole range is pretty ancient in car years.