Sorry for another offset thread but I've searched and cannot find a definitive answer for my specific query and im sure plenty of people will have tried this wheel and tire size already.

Recently purchased a late 2006 R53 JCW (with lowered suspension)... probably 15mm lower than the JCW suspension ( a Sachs Performance non adjustable kit)

I want to get a set of 15x7 whels and run 205 55 R15 for the crappy roads and perhaps 205 50 R15 for the track. I've read many forum posts on offsets but cant seem to get a definitive answer regarding an offset that will result in zero rub.

If anyone can let me know what offset range I can use that will result in zero rub it would be appreciated. I'm keen to get the 17x8 wheels off asap.

(Yes I know caliper clearance will also be an issue.. )

 

36 offset like in 949/6ul wheels works very well. I am using 5mm spacer in the back for 15X8. Not sure if that would be needed for 15x7. I am on stock suspension though.

 

Compared to OEM 16x6.5 et 48

15x7 et36 will be 5.7mm further from inner suspension and poke out 18.4mm more which should work fine.

If you want to be more conservative then try 15x7 et40 which will be 1.7mm further from inner suspension and poke out 14.4mm more.

The reason for the thin spacer for the rear is to clear the lower rear trailing arm using a 15x8" et36 wheel, this is related to offset being not quite enough for the 6UL rim. 7mm closer to inner suspension and pokes out 31.1mm more.

 

Thanks for the info. I thought I was stuck with just et40 to choose from. Looks like i go down to et35 and be OK with the fenders which give a few more possibilities.

I like the weight (and price) of the Konig Dial Ins... time to search the forum to see they fit the JCW brakes

 

Manage to get out for the first decent drive (new car) and I have rubbing issues with the current wheels (wanted to change them anyway!).

Pulling off the wheels it turns out they are 17x8 ET38 with 215 40 17 tires. The rears rub on the the tread face of the tire, very close to the outer edge.

As I'm going to run 205 55 15, if I go for a 35ET my math says this will move the outer edge of the tread face inboard by 2mm (10mm thinner tire, with the center mounted 3mm further outboard)... if so ill probably have to go for ET38 or 40 to be on the safe side.

Does my math check out?

 

OK, not good you have rubbing with 215/40-17 tires which are smaller in tire diameter than OEM. Reason is your suspension is lowered plus the wheels are 17x8 vs 17x7 OEM.

Comparing your current wheels with 15x7 et36 your wheel will be 14.7mm farther from inner suspension and poke out less 10.7mm.

Using 205/55-15 tires should be OK as tire diameter is very close to 215/40-17

 

Thanks for taking the time to reply...first time looking into aftermarket wheels so the help is appreciated.

Hopefully someone can educate me further.. as its the tire tread face that is rubbing (as apposed to the shoulder) shouldn't I be focusing on offset as opposed to rim location (poke etc)?

Using the current set up as an example (215, ET38), if I were to change to a 205 wouldn't this move the edge of the trade face in by 5mm in each side?
If I were to then change to ET35 wheels, regardless of width, this would push the center of the tire out by 3mm (and hence the edge of the tire by 3mm) so id only have 2mm more clearance than currently?
I'm making a novice assumption that a 205 tire tread stays the same width if its mounted on a 6, 7 or 8 inch rim so this could be my down fall.

It would be great if ET35 would fit (as the ET35 wheels I'm looking at are both the cheapest and lightest on my short list!)... but i'm thinking it maybe better to play it safe and go for ET40 or 42.

 

The tire has treads with an inner edge middle and outer edge. When you say tread face what are you describing? The middle treads? If so, what is rubbing on this?

Normally there aren't many places for tires to rub on the MINI, usually the edge of the wheel arch plastic agains the outer tread shoulder or very close to it.

For your other question. The wheel width determines the fit of the tire and how it sits so 215mm vs 205mm tire on the same width wheel will be very close. Therefore it is a combination of the offset and the wheel width that determines how far out the wheel sits. Yes if you make the tire size very very wide or very narrow then you do get some difference but not between 205 and 215.

35mm offset pushes the wheel further out.

Can you take a picture and show where the treadwear is?

 

The tire contacts on the edge of the tread with the rear half of the wheel well. You can feel where the plastic has started to wear away in a arc shape.

I've attached a photo but there has been a weeks worth of sedate commuting since it last rubbed and most of the plastic that deposited itself on the tire has since rubbed off. But hopefully the get the idea from the picture.

Thanks for the help.

 

Your wheel gap does not look very tight so suspension travel (soft suspension) is likely a factor along with wide wheel width. Notice how the wheel pokes out 1 inch. Tire size looks narrow for that wheel so rubbing is along the outer tire edge- this location is very common and to be expected.

As you mentioned the wheel arch plastic is worn where it hits the tire, you can use a dremmel tool and remove more plastic in the same spots to get more clearance but be careful not to get too aggressive.

If you had a wheel that had less poke out offset like 45mm not 35mm then you would get less rubbing. Also tall tire diameter gives you more rubbing risk so don't go taller than 24.3". 215/45-17 is about 24.7" tire diameter but each tire can vary.

Other than the noise of rubbing it isn't that bad to rub the tire, you do wear the rubber and rub the arch plastic. Note when you hear it rub- under a full load of people or when going over dips in the road?

Check your shocks for any fluid leaking, a sign that the shocks are worn and need to be replaced. How old are your shocks? How many miles on them? If they are worn out you might be able to bounce the car by pushing down on one corner. Normally the suspension for the MINI is very firm and you can't move it much.