Tyre sizes

**Tokyo-Joe** · 04-29-2012, 02:32

Hey guys,

I am about to pull the trigger on some new rims and was looking for advice on tyre sizes. I am aiming to fit quite aggressively so a slightly smaller tyre is desired. I also have stoptech calipers all round so will be using spacers to push the rims out further if need be.

F 18" 8.5j +44
R 19" 9.5j +20

I am quite set on a 215/35/18 up front but curious on what to go for the rear. The car is a 91 and I don't want tcs issues.

Thanks!

**nsxtasy** · 04-29-2012, 08:18

Originally Posted by tokyo-joe

i am quite set on a 215/35/18 up front but curious on what to go for the rear. The car is a 91 and i don't want tcs issues.

275/30-19.

**Hapa88** · 04-30-2012, 07:41

Just as a FYI, the tires will look completely different front to rear

A 215/35/18 on a 18x8.5" will be extremely stretched.
A 275/30/19 on a 19x9.5" will be extremely square.

**Tokyo-Joe** · 04-30-2012, 08:37

Thanks for the tips guys.

I would really like a thinner tyre on the rear but am wary of the tcs issues. Something more like a 245/255 would be better for my figment needs I think?

**angus** · 04-30-2012, 10:15

Unfortunately you will need most likely a 245/35/19 in rear to give enough stretch to clear the +20 offset and match the look with the fronts.

Should really be no trouble since it is the factory stagger - 215/245.

**Tokyo-Joe** · 04-30-2012, 10:32

Ah thanks Angus that's exactly what I'm looking for!

**nsxtasy** · 04-30-2012, 12:20

Originally Posted by angus

Unfortunately you will need most likely a 245/35/19 in rear to give enough stretch to clear the +20 offset and match the look with the fronts.

That size won't work safely on a 19x9.5 rear wheel. Most 245/35-19 tires are only approved for mounting on wheels 8.0-9.0 inches wide. Even if you can get it mounted on a 19x9.5, the sidewalls will be stretched and susceptible to excessive heat buildup, possibly resulting in tire failure.

If you can get a narrower 19" wheel, it will work fine.

**Hapa88** · 04-30-2012, 12:29

Originally Posted by nsxtasy

That size won't work safely on a 19x9.5 rear wheel. Most 245/35-19 tires are only approved for mounting on wheels 8.0-9.0 inches wide. Even if you can get it mounted on a 19x9.5, the sidewalls will be stretched and susceptible to excessive heat buildup, possibly resulting in tire failure.

If you can get a narrower 19" wheel, it will work fine.

Safely? Please, it's about hella looking good! I know for a fact you can drive on a super stretched tire. Here's the proof!! (from the Hellaflush thread)

**Tokyo-Joe** · 04-30-2012, 12:54

Let's not drag this thread down the toilet lads.

I've ran more stretched tyres in the past with no issues, it's quite a mild stretch

**angus** · 04-30-2012, 14:00

Yeah, these days a 245 on a 9.5 is almost normal!

Depending on the tire you choose it may not even really be stretched much.

**angus** · 04-30-2012, 14:17

Originally Posted by nsxtasy

That size won't work safely on a 19x9.5 rear wheel. Most 245/35-19 tires are only approved for mounting on wheels 8.0-9.0 inches wide. Even if you can get it mounted on a 19x9.5, the sidewalls will be stretched and susceptible to excessive heat buildup, possibly resulting in tire failure.

If you can get a narrower 19" wheel, it will work fine.

I am guessing you did not consult the books on this one.

245/35/19 IS in fact approved for 9.5" rim on most tires I looked at - in fact a couple were approved for a 10" rim!

Not only that, it is not going to be as stretched as 215 on an 8.5 -

**nsxtasy** · 04-30-2012, 15:51

Originally Posted by angus

I am guessing you did not consult the books on this one.

You are guessing, and you are guessing wrong. I had looked up the Continental ExtremeContact DW, and the maximum width for that tire is a 19x9 wheel. I didn't look up other tires, though, for which it may be okay.

The Goodyear Eagle F1 Asymmetric is the only really good tire I'm aware of that comes in that size as well as 215/35-18 for the front, and 245/35-19 in that tire is approved for 19x9.5 rears.

As for those who think it's okay to mount a tire on unapproved wheel widths, I've had extended discussions with the tech folks as well as the marketing folks for several of the tire manufacturers, and they all roll their eyes at the idea. They all have had extensive experience dealing with buyers/drivers who have mounted their tires on overwide wheels, only to have their tires fail (typically blowouts) due to the excessive heat in the sidewalls. In addition to noting the cause of the tire failure, they were also quick to note that they don't provide any warranty coverage for non-approved installations, so you're on your own if you have a problem.

**Hapa88** · 04-30-2012, 16:35

Originally Posted by nsxtasy

The Goodyear Eagle F1 Asymmetric is the only really good tire I'm aware of that comes in that size as well as 215/35-18 for the front, and 245/35-19 in that tire is approved for 19x9.5 rears.

What about the new Sumitomo HTR Z III (Max Performance Summer)?

**angus** · 04-30-2012, 19:16

Originally Posted by nsxtasy

You are guessing, and you are guessing wrong. I had looked up the Continental ExtremeContact DW, and the maximum width for that tire is a 19x9 wheel. I didn't look up other tires, though, for which it may be okay.

The Goodyear Eagle F1 Asymmetric is the only really good tire I'm aware of that comes in that size as well as 215/35-18 for the front, and 245/35-19 in that tire is approved for 19x9.5 rears.

As for those who think it's okay to mount a tire on unapproved wheel widths, I've had extended discussions with the tech folks as well as the marketing folks for several of the tire manufacturers, and they all roll their eyes at the idea. They all have had extensive experience dealing with buyers/drivers who have mounted their tires on overwide wheels, only to have their tires fail (typically blowouts) due to the excessive heat in the sidewalls. In addition to noting the cause of the tire failure, they were also quick to note that they don't provide any warranty coverage for non-approved installations, so you're on your own if you have a problem.

Actually the DW is about the ONLY tire I could find in that size (including other Contis) that was only approved for a 9" rim - a little strange.

**nsxtasy** · 05-01-2012, 07:18

Originally Posted by Hapa88

What about the new Sumitomo HTR Z III (Max Performance Summer)?

Well, it's not exactly new (it's been on the market for at least five years) but I suppose it's a decent tire too, based on what I've read (I haven't actually driven/ridden on it). I'd still prefer the Goodyear instead though.