18x12 rear wheels - anybody ran them?

Looking at possibly going 18x12 ET44 on my next set of wheels. Need to do some careful measuring to make sure it'd fit, but thought I'd also ask if anyone was running similar already? Any pictures if so?

I'm 18x11.5 ET50 at present, so would be essentially just adding an extra 1/2" to the lip, with inside clearance remaining the same.

Tyre size is currently 315/30/18 and would be staying that way.

Thanks in advance

Any pics of current clearance ? I would estimate that you should be alright.

I run a 10" et20 rear and your proposed set up is only 1.4mm more poke, i can run a 265/35 without too much issue, so going that every half inch and 10mm more width on a tyre keeps roughly the same 'stretch' then that would mean:

10" - 265

10.5" - 275

11" - 285

11.5" - 295

12" - 305

this is fag packet maths

Any pics of current clearance ? I would estimate that you should be alright.

 

I run a 10" et20 rear and your proposed set up is only 1.4mm more poke, i can run a 265/35 without too much issue, so going that every half inch and 10mm more width on a tyre keeps roughly the same 'stretch' then that would mean:

 

10" - 265

10.5" - 275

11" - 285

11.5" - 295

12" - 305

 

this is fag packet maths

Cheers Matt.

Giving me tyre size maths is redundant right enough That has already been decided based on my existing arrangement and they're fine in that sense.

I'm solely looking at where the wheel is going to sit relative to the arch, given that it is flared. I was just curious as to whether anyone else has run that sort of size on a stock arch with a similarly big tyre. I know the inner clearance will be alright. It's just the outside. I really just need to measure it and go from there

For reference, my mate Marc (AB10 on here) is 11" ET17 at the rear, but runs a 265 and camber to clear the arch. I don't want to reduce my tyre size down like that though. I'd be keeping 315/30 anyway. I'll stay 11.5" and perhaps be more conservative at ET43 should I not go 12"

As far as current clearance:

Should be ok

Should be ok

 

http://www.mkivsupra.net/vbb/attachment.php?attachmentid=204069&d=1439474584

Oh I've already been through this

All I need to do is make sure that the 12.4mm extra will be in the right place

Should be ok

 

http://www.mkivsupra.net/vbb/attachment.php?attachmentid=204069&d=1439474584

Where can I calculate this?

Where can I calculate this?

http://www.Wiltheyfit.com

James, I would suspect that with the inside of the tyre being in the same place then the tyre will move outwards from that point, so I believe the tyre walls will begin to 'stretch' and the tyre tread will move with it, I dont think the thread will move tthe full 12mm maybe only half so 6mm, meaning the top of the tyre will be 6mm closer to the arch. I know you are looking for someone with experience, I am just trying to help.

Speak to Jazz as he runs a 12" rear wheel.

http://www.Wiltheyfit.com

 

James, I would suspect that with the inside of the tyre being in the same place then the tyre will move outwards from that point, so I believe the tyre walls will begin to 'stretch' and the tyre tread will move with it, I dont think the thread will move tthe full 12mm maybe only half so 6mm, meaning the top of the tyre will be 6mm closer to the arch. I know you are looking for someone with experience, I am just trying to help.

 

Speak to Jazz as he runs a 12" rear wheel.

Absolutely Matt - I appreciate the postings also

Precisely that - I am not certain by how much the tread will move, that is the factor I can't confirm having not put a 315/30 onto a 12" rim before compared with how it sits on the 11.5".

I think that I've made my mind up. As I have quite an aggressive roll & flare on the arch, I'm going to brave it and go 18x12 ET44 with the 315/30.

Now for the fronts (aiming for 18x10 ET36 285/30 there).

(And the expense, of course!)

Now for the fronts (aiming for 18x10 ET36 285/30 there).

 

(And the expense, of course!)

Do you have the tyres already for the front ? I would probably run a 265/35

I run a 225/40 on a 10" front ET20

Do you have the tyres already for the front ? I would probably run a 265/35

 

I run a 225/40 on a 10" front ET20

Yep I'm currently 285/30 on 18x10 at ET41.

Yep I'm currently 285/30 on 18x10 at ET41.

Oh ok, so you are putting a 5mm spacer on ?

Oh ok, so you are putting a 5mm spacer on ?

No no - I'm buying a new set of wheels It just so happens that my existing wheels aren't too far off in sizes, so I'm working round that to spec them.

Don't know if this helps at all, but I'm running a 19x10.5 et30 with a 305/30 tyre and the rear arches only needed rolling out a tiny bit. With a 35 profile tyre they would need rolling slightly more, but figment is surprisingly good.