Wheel Size for Track Days

[Forg]

Might be worth checking that you can fit 4 tyres in the car. It should be possible (the sedan rear seat folds down dunnit?), but you’d want to be completely sure; might affect your choices.

If it were me, my skills probably aren’t good enough that a track-only tyre would make a difference to my performance. But for others, it can make a decent difference, so if you can get away with not needing to use ‘em on the road you could be better off.

 

[Thomas_D]

Might be worth checking that you can fit 4 tyres in the car. It should be possible (the sedan rear seat folds down dunnit?), but you’d want to be completely sure; might affect your choices.

If it were me, my skills probably aren’t good enough that a track-only tyre would make a difference to my performance. But for others, it can make a decent difference, so if you can get away with not needing to use ‘em on the road you could be better off.

Sedan rear seats don't fold down, that's my biggest gripe with the car

 

[villn808]

Sedan rear seats don't fold down, that's my biggest gripe with the car

I used to have a set of the SF01s for drag racing, they both fit in the boot, very tight squeeze.

The 17s and 305/45s I have now no chance.

One goes on the back seat with old towels and seatbelt on now lol.

 

[Thomas_D]

I used to have a set of the SF01s for drag racing, they both fit in the boot, very tight squeeze.

The 17s and 305/45s I have now no chance.

One goes on the back seat with old towels and seatbelt on now lol.

Yep back seat no probs.
Which leads me to ask what would be the optimum wheel/tyre size combo for track use?
Quote Villn808 "Koya SF01 staggered 18x9, 18x10 with some semis would be ideal"
If I can clear the brakes with an 18" wheel then tyre size? Width? Profile(tyre)? Offset?(wheel)Any advantage by retaining same rolling diameter or is there a better option?
Mine's lowered so again there's clearance issues with the arches.

 

[villn808]

Yep back seat no probs.
Which leads me to ask what would be the optimum wheel/tyre size combo for track use?
Quote Villn808 "Koya SF01 staggered 18x9, 18x10 with some semis would be ideal"
If I can clear the brakes with an 18" wheel then tyre size? Width? Profile(tyre)? Offset?(wheel)Any advantage by retaining same rolling diameter or is there a better option?
Mine's lowered so again there's clearance issues with the arches.

I would contact Koya direct and they will help you out, they are good to deal with.

I only had the rears and they were 18x10 +45.

A squared set up would probably be fine for the track, 18x10 all round. You don’t have to worry about tram lining on track. Otherwise 18x9 front.

Tyres, something like a Toyo R888r. They come in a heap of sizes. Staggered you could go with 255/35/, 295/30. They also make them in 265/35 and 275/35

The SF01 definitely clear the brakes as per photos above.

I don’t see any advantage to keeping rolling diameter the same for a track tyre,

 

[Thomas_D]

I would contact Koya direct and they will help you out, they are good to deal with.

I only had the rears and they were 18x10 +45.

A squared set up would probably be fine for the track, 18x10 all round. You don’t have to worry about tram lining on track. Otherwise 18x9 front.

Tyres, something like a Toyo R888r. They come in a heap of sizes. Staggered you could go with 255/35/, 295/30. They also make them in 265/35 and 275/35

The SF01 definitely clear the brakes as per photos above.

I don’t see any advantage to keeping rolling diameter the same for a track tyre,

Thanks Villn, some good info there.
I'll call Koya tomorrow

 

[Thomas_D]

Ok, spoke to the nerve center at Koya this morning. Factory offsets are 48 respectively.
Koya are recommending:
18x9 Front, offset 32 or 35 (pending brake clearance) Tyre 245 or 255 /45
18x10 rear, offset 42 Tyre 275/40

If my calculations are correct, running less offset will push the wheel outwards by 13 to 16mm and potentially rub on the guards, roll the guards to fix?

Question: Will running different offsets strain the steering and suspension components enough to be a concern? What about the steering geometry by running a wider track?
Cheers

Edit: Just realised the different offset in the rears will be offset (pardon the pun) by the different width rim (rear) 9.5inch factory versus 10 inch Koya.

 

[villn808]

Ok, spoke to the nerve center at Koya this morning. Factory offsets are 48 respectively.
Koya are recommending:
18x9 Front, offset 32 or 35 (pending brake clearance) Tyre 245 or 255 /45
18x10 rear, offset 42 Tyre 275/40

If my calculations are correct, running less offset will push the wheel outwards by 13 to 16mm and potentially rub on the guards, roll the guards to fix?

Question: Will running different offsets strain the steering and suspension components enough to be a concern? What about the steering geometry by running a wider track?
Cheers

Edit: Just realised the different offset in the rears will be offset (pardon the pun) by the different width rim (rear) 9.5inch factory versus 10 inch Koya.

The sizes and offsets Koya gave you are perfect, definitely not too aggressive.

I would get the guards rolled if lowered. There’s no downside to this if done correctly.

As far as steering geometry and strain on components, track days in general are hard on a car. But one every now and then isn’t going to matter. Maybe if you were hammering it every weekend you’d see accelerated wearing on bushings ect.

I got a specific track alignment when I did my track day and got it reset after, maybe something you could look at.

Don’t overthink it too much mate. Chuck the wheels on, set the height if you got coilovers and get it aligned. Then go out there and have fun.

One other thing definitely look at an oil cooler if you haven’t got one. Things get hot out there pretty quick otherwise.

 

[Thomas_D]

The sizes and offsets Koya gave you are perfect, definitely not too aggressive.

I would get the guards rolled if lowered. There’s no downside to this if done correctly.

As far as steering geometry and strain on components, track days in general are hard on a car. But one every now and then isn’t going to matter. Maybe if you were hammering it every weekend you’d see accelerated wearing on bushings ect.

I got a specific track alignment when I did my track day and got it reset after, maybe something you could look at.

Don’t overthink it too much mate. Chuck the wheels on, set the height if you got coilovers and get it aligned. Then go out there and have fun.

One other thing definitely look at an oil cooler if you haven’t got one. Things get hot out there pretty quick otherwise.

Great!
Bought the car with coilovers, it appears to be pitched a little nose down, not really sure if I should bring the rear down to level it off, which will require a wheel alignment I guess.
Yep, getting an oil and transmission cooler soon.
Now to find a good road/track tyre in those recommended sizes, is anything better bang for buck than Pilot Cup 2? Looked at Yoko ADO8R but couldn't find the sizes.
Cheers

 

[villn808]

Great!
Bought the car with coilovers, it appears to be pitched a little nose down, not really sure if I should bring the rear down to level it off, which will require a wheel alignment I guess.
Yep, getting an oil and transmission cooler soon.
Now to find a good road/track tyre in those recommended sizes, is anything better bang for buck than Pilot Cup 2? Looked at Yoko ADO8R but couldn't find the sizes.
Cheers

Nankang AR1 come in come in 245/40 and 275/35. Slightly smaller side wall than recommended.

I can’t find any semi slicks in sizes they recommended.