I've just been reading up a fair bit about wheel offset. I understand what offset is and how it is measured but what I need a bit of help with is understanding how it effects the car. I am looking for a new/2nd hand set of wheels in 18" and think I need an offset of around 51mm.

The wheels I have seen that I like have an offset of around 37mm to a max of 47mm. Lots of scoobs have this offset (rim is Advan RS/Rota G-Force) and looks really good but how do they get away without rubbing on the arch or on the strut.

I want a pronounced dish in the wheel and I think the higher the number of the offset the less the dish is. Don't know if this is right or not.

How do these guys get away with an offset so far away from the original spec?

Could someone please advise? Thanks.

 

Does anyone know about this?

 

Higher the number the more the wheels will be sunk into the arches. The lower the number the more the wheels will stick out, often allowing larger brakes to be fitted. The lower the offset against the factory recommended the more scope there is to faff up your bearings/hub I am told.

As an example a WRX Prodrive PWRC1 is ET52 in a 17" and ET53 in an 18". These will not clear a brembo brake upgrade.

STi fitment in the same wheels if ET46 to allow that clearance.

I have found the most common sizing to be ET48 on 18's of good quality such as Speedline/Rota etc, but for the most part many offsets are offered by the bigger companies.

Clearly the lower/higher the offset to the extremes of your factory tolerances, the more chance there is of rubbing if you simultaneously increase the width of your tyres.

Best thing to do is find a wheel you like and then post up the ET options you have

 

you're best sticking as close to the factory as possible. My Rota's run 48mm with no rubbing/clearance issues on a bugeye and that's lowered 50mm with 235/40 tyres on 18s. Much more and they look like they'll start catching, and as already mentioned, it'll start putting pressure on you bearings.

 

Thanks guys all seems to make sense. I cant find a place just now that sells the rims I am looking for, just been searching for the last 20 mins. Found it last night. Anyway, here's the rims I think I'm after and how I'd like the car to look, with the dished effect. Now I'm wondering if I can achieve that?

1st style



2nd style


The higher the offset in both styles above, the more the center of the hub is pushed out so the flatter the whole rim looks. You loose the concave. The cars have a very pronounced concave which is what I'm after, which I think has to be on a low offset. Thats where I think I'm gona come unstuck

 

Try here for those sort of styles...

6 great reasons to buy Rota wheels from RotaShop.co.uk – The UKs leading online Rota Wheels web store

 

Thanks, stumbled across that site a wee while ago. Seems like the rims I'm after only come in 18 x 9 which I'm wondering may be a tad wide? Then, in that size the offset is 30 I think. I'm wondering if I'm trying to fight a loosing battle?

 

Rota Force and Rota Torques.

I have the Torques on both my scoobs, really nice wheel.

YouTube - MY06 STi Spec-D Blitz Nur-Spec S

 

Looks pretty sweet, sounds the dogs too. I reckon your classic is needing lowered though

 

Needs lowering a touch

 

Wide arch kit

 

That would be an option I suppose but not wanting to go down that road. Well not at present anyway. The pics I posted above look to be standard arches though.

 

Arch rolling is pretty common in the US though to accomodate larger wheels. Plus they then tend to run skinny tyres to cope further, which leaves expensive rims exposed.

 

18x9 advan rs 45 offset ,just to give you an idea of how it looks mate .

 

Thats looks smart as f*ck, I want them! What size tyre are you running? I take it no probs with rubbing. Just wondering if the tyre could go ever so slightly wider, they look a wee bitty stretched.

 

This is how 8x18s with 235/40s fill the arches...

 

Anything between 48-53 is perfect, thats what you should be aiming for

Tony

 

The wheels I've been looking at have an offset of 48, so they should be ok, thanks.

JonMc - Wot offset are your wheels?

 

48mm