What's the ideal wheel size for sportscars? at what point

>>15902381
17 or 18s.

Fifth gear or someone tested it

>>15902381
>>15902397
But desu, you can't fit a Brembo big brake kit inside tiny 17" wheels

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>>15902381
19's... r-r-right guys?

>>15902381
From an aesthetics standpoint I wouldn't ever go beyond 21's, and that would have to be on a suitably big and ludicrous car too. Seeing shit like 21" rims on an Audi A7 kills so much of the class a car like that has. Speaking solely from practicality, 18" seems like the reasonable maximum to avoid frequent scratching/curb rash.

>>15902381

It varies car to car. IMHO, they'd be the the closest middle ground between the factors of being just as small as possible while still clearing the brakes while also being just large enough that a 40 or 45 sidewall'd tire fits fits naturally. 17's on a Miata would be way too big while putting 18's on a modern Porsche would be way too small.

depends on the car and application.

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20's look just fine imo

too much rim make the ride too hard

>>15902381
After actually having driven sports cars with multiple wheel/tyre sizes I can say that the bigger wheels/slim profile tires combos are shit for sports cars, especially older ones that don't have the suspension tuned for them, plus if you go to far over stock it not only fuck's with the speedo, but the gear ratios as well, the sweet spot is either 16"-17", with preference to 17"

Smaller sidewalls definitely improve tire response but the weight and loss of compliance totally isn't worth it.

14-16 for tiny lightweight cars
17 for modern sports cars

Anything that comes with/requires larger ain't a sports car, it's a landbarge.

Another note, finding quality street tires for <16" wheels is near impossible nowadays, won't be long until 16's are hard to find, hope it doesn't affect 17s too.

Race rubber is made in all sizes, but lets be honest here...

>>15902381
there is no single idea wheel size you retard

>>15902511
What? You have no idea what you're talking about.

Wheels size matched with a proper tire wont change anything except sidewall hardness which adds to steering response and increases ride hardness. Depending on the weight of your wheels you can decrease your unsprung mass too.

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>heavily melanin enriched people like big wheels
>so much so they will rent/finance 20"+ wheels
>get low pro tires on them probably also financed
>drive like assholes
>hit potholes and break their donk wheels
>mfw

>>15902610
>wont change anything except sidewall hardness which adds to steering response and increases ride hardness.

Good job describing exactly how old suspensions designed for tall soft sidewalled tires don't do well with stiff modern lo-pro's.

I have 18's on my S197 GT.

Just right.

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Dem factory 20s tho

>>15902729
He's talking about the speedometer. All that matters is outside diameter of the tires when it comes to the accuracy of the speedo. Changing the rim size won't change the total diameter if you size the tires correctly, unless your donk wheels alone have an even larger diameter than the stock wheel/tire setup.

15x8s on the rear and 15x7s on the front. With a bigger tire.

>>15902787
Those look like civic wheels.

Also if you get an A7 or S7 in anything other than dark gray or black you're a fucking chode

Low profile wheels are a good idea if your AWD system can destroyed because of a flat tire. Example DSM's and 3000GT. FWD based systems are immune to this.

>>15902787
Have we reached peak diameter yet? I don't think that looks good at all.

Pick your tires then buy your wheels. There's tons of wheel options out there, but tire choices are limited.

If you want to run 285-335 street tire you need 18" wheels minimum. If you are okay with a 245 then you can get by with a 15" wheel. 275 street tires used to be popular for 17" wheels but they are drying up.

Most street cars don't really need as much brake as you can cram behind an 18" wheel.

Besides if you do it right you can fit a very nice 4 piston caliper with a 12-13" rotor behind a 15" wheel, which is plenty for most non-pig fat street cars.

For drag racing, having sidewall flex is really important for traction from a dig. Real drag wheels and slicks are 15"-16", while the largest they generally go is 18".

>>15902461
Yeah on your 2 ton truck you call a sports car.
But for everything else smaller than a minivan it looks like a donk

>>15903408
why not go overkill on brakes apart from cost?

like seriously, i've always gone massive overkill on my brakes because it's nice to have that massive safety net of stopping that much faster.

and yes, there is a difference between massive aftermarket 6pot brakes and mid-range ones.

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Pretty much every sports car series uses 18" wheels

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Well the obvious answer is 17"

>>15902461
20's look good on muscle cars

>>15903630
Fuck off

>>15903906
Too much tire desu
>muh comfort
>no grip

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>>15902407
If you can't go bigger, you have to go more.

>>15903906
yeah nigga 17s are perfect on a FD

>>15904057
you're opinion a shit

>>15902412
18" would be best, but i like my 19" coupe rays. plus it fits my brembo brakes

>>15902507
Tell that bitch hop out, walk the boulevard

>>15905532
Tfw recognize song but not song name

>>15905912
Molly by tyga

>>15902428
uh my miats rolls on 17s. came like that stock

>>15902824
Ok genius, start out with a car that has 195/60/14 tires and try to go +3/4 and not have to adjust the speedo, doesn't fucking happen unless you like the speedo reading wrong, and he was talking about the suspension as well but your autism flared up when you say the speedo comment apparently

>>15902381
You actually want the smallest possible wheels. Less unsprung weight = better performance. Just make sure you have adequate brakes.

Bigger wheels is actually just a meme created by manufacturers. Because of modern safety regulations, they need extremely high belt lines, and so they need to go bigger and bigger on the wheels to keep them visually appealing.

>>15902507
So tune your suspension accordingly.

>>15902610
>Le sidewall meme
Lower unsprung weight (and thus smaller wheel size) is more important than sidewall stiffness.

>>15905928
it's rack city you fucking ignorant nigger

>>15906059
Pretty sure speedometers are off from the factory boyo

Get it close enough and it's not an issue

>>15903785
Because fancy big race brakes may not get up to proper operating temperature, and they add unsprung weight.

>>15906075
you need big wheels to accommodate big brakes though.

ofc that does not apply to my mate's 1.2l diesel toyota auris that has 17" wheels

>>15903906
Looks great. Big chunky wheels are nice to see.

>>15902787
honestly i think this looks like shit. 19's would look much better.

>>15904070
> Have outboard brakes
> Have inboard brakes too

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>>15902407
>implygig

>>15906059
>current year
>not just using this

https://tiresize.com/calculator/

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>>15902381
As long as the profile isn't thinner than pic related it's fine.

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>>15902381
>What's the ideal wheel size for sportscars?

Obviously, the one that can fit the best tire FIRST and foremost.

Secondly, larger wheels provide more stability at higher speeds than smaller wheels, while smaller wheels provide better acceleration.

Thirdly, aspect ratio is also important because if it's too high you will get a lot of sidewall flex and if it's too low your steering response will feel more twitchy/unstable and you risk damaging your wheels outside of a smooth racetrack

>>15904070
Tiny brakes stop as good as huge ones, tires are the weak link here. The big ones can dissipate a lot more heat, though. You want more rotors, not more calipers.

>>15904070
All that effort an it's still a Hyundai

>>15902381
31x10.5 r15 on 8" wide rims

>>15902381
26s

literally the sole reason for tiny sidewall 20" wheels is so you can fit big fat 15" rotors with 6 piston calipers and shit in them

>>15906716

Ofcourse larger brakes will stop better than small ones.

>>15903785

I want the smallest brake that will do the job. I always prefer rotors that are super wide, but relatively small diameter. I like a nice 12-13" rotor that's 1.25" wide minimum or more ideally 1.5" wide. 6 piston calipers are more or less a joke on street cars. A 4 piston caliper is plenty for anything even performance and track oriented 3,500 lbs and less. A properly designed 4 piston usually has the best compromise of weight, flex, clamping force, and piston area.

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>>15906111
>proper operating temperature

Watched too much top gear have we?
Steel brakes takes like 0.2 seconds of hard braking to reach 150'c (300'f).

It's the carbon ceramics who takes a while to heat up.

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>>15906207
One of the calipers are for the hydraulic handbrake.

>>15906716
Are you retarded?

>>15907712

I've had circle track race cars where the brake pads wouldn't even work under 300 degrees. Some closer to 500 degrees. I'm not sure I've even seen 500 degrees on my street car at a track day.

>>15907740
Because modern disks are ventilated, which cools them down, but they heat up massively while under the force of brake fluid and right foots.

>>15902407
You can fit 2 and 4 pot BBKs within a 17.

>>15907789

The circle track rotors are wider and better vented then just about anything but the most exotic production car discs. They also have cooling ducts. The typical operating range was 500-1200 degrees. The best ones were floating too like a NASCAR or high end road race car so the rotor is always perfectly centered in the fixed caliper.

>>15902412
>19 inch rims
>260-280hp
>cheaper than BMW
>Gets 29mpg if you drive it pussy
Based Infiniti G35, they really did something right with that thing.

>>15904070
I can almost feel the discs screaming in agony
https://www.youtube.com/watch?v=9P_AI5hZDEY

I say we argue less R size and more on how much sidewall you need

>>15907812
Nobody gives a shit about your dirttrack whatevers.

And the fact of the matter is that even DOT5.1 fluids BOIL at 500f.


Are you literally insane to think those temperatures can be reached by brakes, actually, metallurgically tempering the fucking steel to the point where the soft rotor gets brittle?

How fucking full of bullshit are you senpai, stick to downgearing for braking effect, cause somebody ought to take away your ability to brake a car for saying that much piss.

>>15902381
>assuming RWD
front wheels between 17" and 19" between 225 and 295 wide depending on what fits and if you track or DD.
>exception: 305's on 20"s if you Camaro Z/28

rear wheels between 18" and 20" between 275 and 355 wide in the rear also depending on what fits and track or dd

My car has ventilated two piece
13+ inch M3 CSL rotors front and rear. You would be hard pressed to fit those under 17" wheels tho it can be done. 18" is perfect for a street sports car with large rotors, 19" for show.

>>15906696
>Big wheels are more stable
Bullshit. The difference in rotational inertia is insignificant compared to the moving inertia of a car's body.

>Much sidewall flex
Meme invented by manufacturers. Insignificant compared to the gains created by lower unsprung mass. Basically, belt lines need to go up because of safety regs, wheel size go up to match (otherwise cars look ridiculous), and manufacturers try to sell these big wheels as a performance advantage.

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>>15903630
the topkek

>>15908303
does that apply if i drive an ae86?

>>15909462
no you need like 700 hp for tires like that to be usefull

>>15909489
>700
More like 400-500, especially on a live axle like the AE86.

>>15902423
>A7
>class

Wat

>>15907843

>Get smoked by a Hyundai half its price on the regular.

>Something right

>>15902534
911 turbo S disagrees