afadeev said:
P.S.: For track wheels, you remove #2, and add low-weight and strength requirements.
I wouldn't say light-weight is a track-specific requirement. That's why Tesla spent so much extra money equipping even their base Model 3 will lightweight 18" wheels that have roll-forged rims for and excellent strength to weight ratio.
I certainly hope that Tesla wasn't all-out optimizing its 18" wheels for weight, because if they did, they didn't do so well (actually, I know they were optimizing for aerodynamics, not weight).
I, actually, love 18" Aero wheels, unfortunately, they wont clear my TM3P rear brake calipers, and are paired with Pirelli winter tires (which I dislike). Thus, I had to go aftermarket for my 18" wheels.
BTW, "roll forging" is an industry misnomer, as such wheels are not really forged, at all. Tesla is not the only wheel supplier to misuse that term, so no harm to fault.
For what it's worth:
- 18x8.5" Tesla aero wheels weight 21.6".
- BMW 18x9" (wider) 513M wheels weight 19.1".
- You can buy inexpensive "roll forged" Apex ARC8 18x9 wheels that weight 18.0".
- Truly forged wheels 18x8.5 wheels (e.g.: BBS RF) will weight in at around 16.5".
If someone wants to learn more about forged wheels, see the following nicely illustrated article about how Forgeline does it:
Faster, Lighter, Stronger How Forgeline's Monoblock Wheels Are Built - LSX Magazine
Light wheels reduce demands on the dampers (shock absorbers) and help significantly with efficiency in typical urban traffic.
Light weight wheels definitely reduce unsprung suspension weight, and thus it is easier and faster to change their rotational momentum. Therefore, lighter wheel + tire combo (folks always forget to consider tire weights, which vary significantly) will improve acceleration and braking efficiency.
Both are very good things, but they do come at a price.
Simply lighter wheels give up some strength and are more susceptible to bending from pot hole encounters.
Forged wheels compensate for that with much greater strength, and are also much lighter, but are much more expensive.
I will always pay more for high-quality wheels because wheels are basically what makes it a car! Heavy, cheap wheels suck!
Agreed, until you throw $$ into the equation.
If $$ are not a constraint - always buy
real forged wheels!
If they are, then each person needs to find their preferred spot on the {price, strength, weight, looks} compromise spectrum.
a