Square Setup for GT

[Pnbnationsbest]

225/40/19
225mm wide
40 is the sidewall height
19 is the diameter in inches

 

[moinmoin]

Front tires 225/40/19
Rear tires 255/35/19

Actually 40 and 35 respectively are aspect ratios.
Aspect Ratio is the ratio of the height of the tire's cross-section to its width, in other words, the sidewall heights of each tire are 90 ( for the 225) & 89.25mm (for the 255) respectively.

225 x .40 = 90 mm or 3.543"
255 x .35 = 89.25 or 3.514 "

Technically, the front tires are taller, but the difference is minimal.

 

[MerlintheMad]

Actually 40 and 35 respectively are aspect ratios.
Aspect Ratio is the ratio of the height of the tire's cross-section to its width, in other words, the sidewall heights of each tire are 90 ( for the 225) & 89.25mm (for the 255) respectively.

225 x .40 = 90 mm or 3.543"
255 x .35 = 89.25 or 3.514 "

Technically, the front tires are taller, but the difference is minimal.

That is "technically" indiscernible not just minimal.

Where/how do you come by this information?

Thanks.

 

[Sybaritic]

Hi all, im starting to shop for aftermarket wheels, but when you like say a 19” by 9” wide wheel, how do you what tire size to settle on? Do you use the stock OEM tire size as reference, or do wheel manufacturers give you a range of sizes to choose from?

 

[MerlintheMad]

Hi all, im starting to shop for aftermarket wheels, but when you like say a 19” by 9” wide wheel, how do you what tire size to settle on? Do you use the stock OEM tire size as reference, or do wheel manufacturers give you a range of sizes to choose from?

It's usually listed with the tire; narrow to widest rim sizes that work.

 

[moinmoin]

wheel manufacturers give you a range of sizes to choose from?

 

[Sybaritic]

View attachment 39937

Thanks very much, moin-moin !

 

[Hockster]

Nitto's site lists every dimension you need for their tires, very useful. Also includes recommended wheel sizes. Here's the NT555 G2 page:
NT555 G2 Summer Ultra High Performance Tire

 

[Frank D Harders]

I read the numbers for matching. I've never bothered to learn what they actually refer to. Hah. So, what does "255" mean? What does "35" mean? To me, they are just numbers.

(By the way, you're fairly new, or by post count less frequent, here, so you don't know my story; tl;dr: this is my first brand new car - and so far only brand new car. I've only driven vans and other "family" vehicles my entire adult life. Tires, like the rest of the car, are tools on vehicles like that; "I am not a car guy" is an adopted self description. But, I am a Kia Stinger Guy. )

New member. Kind of car guy know enough to get into trouble. Jack of all trade master of none.
Tire info
Front 235/40/19
235 is width of tire
40 is height of tire.
There is more info on the tire as well. Will tell u speed rating of the tire how soft / tread wear to be expected ect.

 

[Frank D Harders]

Anyone have opinion on best tire for this car. Last car i had that required consideration of tire was 2006 STI. 9yrs ago. Best tire then was a hankook. Tires really can make a difference in over driving experience.

 

[Gtecko]

Like what I've said above running 255's all around with bolt pattern 5X114.3 with 19X8.5 +30 Offset All Around. Wheels is ESR RF2! Lighter than the OEM wheels.

Here look at it lowered on H&R Springs
View attachment 38150

well I was looking at 19x8.5 et 35 Niche Vosso and wasnt sure if squared would do it but reading and seeing you car... it is what Iam buying now !
Thanks !

 

[Jrmopar02]

Well, I'm mistaken again, then. Do you happen to know what the offset number of the OE rear wheel is?

What are the offsets

 

[MerlintheMad]

What are the offsets

OEM front offset 34
OEM back offset 46.5

Welcome.

 

[NickK]

OEM rear won't work on the front cause it won't clear the big brakes because of the offset.

Aftermarket Wheels will work! I'm running a square set up with 19X8.5 with 255's all around.

What offset did you use all the way around?
Sorry if I missed it. This is confusing me. I just want to square up my GTS without a lot us fuss. Thank you

 

[Thomby]

What offset did you use all the way around?
Sorry if I missed it. This is confusing me. I just want to square up my GTS without a lot us fuss. Thank you

- We know 8" +34 (stock fronts) clear the inside. An 8.5" +46.5 (stock rears) would add 1/4" width on the inside edge and shift inward 1/2", ie need an 18.5mm spacer (or offset reduction) to put the inside edge back to stock. That's 46.5 - 18.5 or a +28 wheel...call it +30 offset.
- We know the stock 8" +34 fronts with a +20mm spacer are pretty flush with the fenders. An 8.5" +46.5 (stock rears) would have their outer edge about 1/4" inboard of the stock 8s (add 1/4" on the outside edge, shift inward 1/2", net loss of ~6mm). That's 46.5 - 20 - 6 or about +20 offset.

- Rears are easier since we know the stock 8.5" +46.5 clears the inside, and with 20mm spacer sits flush with fenders (equivalent to 8.5" +26.5 offset).

So +20-30 offset for fronts and +25-45 for rears. And the same offset front/rear will leave the fronts about 1/4" or 6mm further inboard, which you may or may not notice, but can correct with an extra 5mm of spacer up front. So for example, an 8.5" +30 with 5mm front spacer and no rear. Or an 8.5" +45 with 15mm rear and 20mm front spacer, etc.

Hellaflush wheel guys please check my math...

 

[NickK]

- We know 8" +34 (stock fronts) clear the inside. An 8.5" +46.5 (stock rears) would add 1/4" width on the inside edge and shift inward 1/2", ie need an 18.5mm spacer (or offset reduction) to put the inside edge back to stock. That's 46.5 - 18.5 or a +28 wheel...call it +30 offset.
- We know the stock 8" +34 fronts with a +20mm spacer are pretty flush with the fenders. An 8.5" +46.5 (stock rears) would have their outer edge about 1/4" inboard of the stock 8s (add 1/4" on the outside edge, shift inward 1/2", net loss of ~6mm). That's 46.5 - 20 - 6 or about +20 offset.

- Rears are easier since we know the stock 8.5" +46.5 clears the inside, and with 20mm spacer sits flush with fenders (equivalent to 8.5" +26.5 offset).

So +20-30 offset for fronts and +25-45 for rears. And the same offset front/rear will leave the fronts about 1/4" or 6mm further inboard, which you may or may not notice, but can correct with an extra 5mm of spacer up front. So for example, an 8.5" +30 with 5mm front spacer and no rear. Or an 8.5" +45 with 15mm rear and 20mm front spacer, etc.

Hellaflush wheel guys please check my math...

Thank you for your help. However I feel more confused now than I did starting into this. Is there a simple formula that you would recommend I use? I'm really looking to be able to rotate my tires so I can stop spending a small fortune on tires.

 

[Snicklefritz]

Thank you for your help. However I feel more confused now than I did starting into this. Is there a simple formula that you would recommend I use? I'm really looking to be able to rotate my tires so I can stop spending a small fortune on tires.

No formula. Depending on the actual wheel, a close offset will or will not clear in front. Rear is no problem. I've never read of anyone rubbing the suspension in the rear. Folks who insist on flush to some poke will get rub or even abrasion on the outside from the fender or up inside the wheel well when cornering harder than usual.

You don't want any of that. So remain conservative and you should be fine.

You haven't said anything about how you want this to look, in other words how wide you prefer to go. You cannot really run a staggered 8.5" wide OEM wheel up front. Offset is too big at 46.5. It will rub the strut.

I have an aftermarket 8.5" wide wheel in front with a 39 offset, which is 5 bigger than OEM on the 8" front wheel which has an offset of +34. The OEM squared offset is that 8" +34 wheel with 225/45/18 tires.

You have to decide on 18", 19" or 20" wheels. Then tire width. Then an offset that will clear with the tire width in front - narrower tire like the OEM 225, keep offset under +40, wider tire, reduce offset accordingly, probably between +30 and +35.

Best advice I can offer, use a professional tire and wheel shop. That way you will clear with whatever they find for you.

 

[Thomby]

Thank you for your help. However I feel more confused now than I did starting into this. Is there a simple formula that you would recommend I use? I'm really looking to be able to rotate my tires so I can stop spending a small fortune on tires.

The "formula" is really just starting with combinations that we know fit on the inside, or look flush on the outside, and the fact that 1 inch = 25.4mm.

So going from 8" to 8.5" wheels in the front means, at the same offset, you'd have an extra 1/4" (6.25mm) inside and out. Then going from +34 (stock fronts) to +46.5 (stock rears) shifts the wheel inward 12.5mm (1/2"), meaning your inside edge is now a full 3/4" or 18mm further inward, which is why they won't clear.

A 15mm spacer would push the inner edge about where it was stock (3mm further inward, but close enough), and your outer edge would go from 1/4" (6mm) more sunken in to about 9mm (0.35-0.4") further out. A +46.5 offset with a 15mm spacer is a +31.5 offset. So you could run a +30 with no spacer, a +40 with 10mm spacer, etc.

I have an aftermarket 8.5" wide wheel in front with a 39 offset, which is 5 bigger than OEM on the 8" front wheel which has an offset of +34. The OEM squared offset is that 8" +34 wheel with 225/45/18 tires.

Going from 8" to 8.5" wheel at the same +34 offset means an extra 1/4" or 6mm of wheel on the inside (and outside), and going to +39 offset shifts it inward another 5mm. In other words, 11mm or about 1/2" extra space needed on the inside. But the extra +5 offset on the outside basically cancels out the 1/4" of extra wheel and puts your outer edge in about the same place as stock which I assume was the goal.

It also means you could add up to +20mm spacers all around to flush all four tires out to the fender without rubbing, and regain the lost inside clearance up front.