My ways of defining a cool car:
Pros:
1. Is it outrageous?

2. Is it revolutionary in it's styling or it's engineering? đź’ˇ
3. Does it have sexy, agressive, fast, or interesting/curious looks?

4. How is it's character?

5. Does it's looks match it's character?
6. Does it's performance/sound match it's character?
7. Is it reasonably fast?
8. Is it a fire-breathing monster? (Absolutely mad car or a racing car)

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9. Is it a Lamborghini? (Being one makes it automatically Sub-Zero. Exceptions apply though).
10. Is it a recognizable car/legend/head-turner?

11. Does it have some sort of "Surprise/History factor" or any special deed done? ("It has a rotatory engine"/"It's the first 4WD Porsche"/"It, or it's closely related race version won the 24H of Le Mans").
Cons:
1. It has a dull, boxy, or "wanna-be" styling.
2. It looks like it has been riced.

3. Cant manage to make a graceful left-right turn at a corner. (See: Some Muscle cars and Dragsters).

4. It is a "Sober and elegant" car, but with high performance. (See: RR Phantom/Maybach 62).

5. It's an SUV/CUV/MPV/Pick-Up or any niche of the market that resemble one of those. Doesnt apply if it's a pure, purpose built, off-roading vehicle.

6. Cars that dont go outside the box both in styling and performance terms.

7. Cars with lazy engineering (8.0L engine developing...250HP! 👎).

8. Cars that are prone to attract gold diggers (He's driving a Ferrari...maybe i could have his life insurance).

9. Heavy cars.
10. Cars owned by bussinesmen or anyybody that would produce a boring and uninteresting conversation.

11. Ford cars. There is a reason why Henry Ford is criticized and is a god-like character in Aldous Huxley's "Brave New World", and unless it's a race car, a Ford GT, or a muscle car, this rule deems it automatically seriously uncool (Much like "Pro" rule #9).
I select the rules (the Pros and Cons) that apply, add them and take that as 100%. Then i work out the actual "cool" percentage the car has.
<65=Seriously Uncool
Between 66 and 75=Uncool 👎.
Between 76 and 85=Cool
85-95=Sub-Zero.
Pros:
95-100=Lord Kelvin's Ice Box!

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That's just my opinion

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