Well, I've decided on a set of wheels and I'm going to go with an 18x8 and 215/40/18s.

The offsets offered are 40 and 45 and I'm getting conflicting reports on what's best. Can someone please advise? (R56)

Thanks!

 

40 will be better. 45 may cause inner clearance issues

 

With that skinny of a tire, you will NOT have clearance issues with the tire on the +45 wheel. The wheel will be very close to the strut, though. If you've got aftermarket coilovers, the wheel edge might contact the strut.

--Dan
Mach V

 

This is 18x8 +45 with 225/35R18, factory struts. No clearance problems.



Hmm. You're going with a 215/40R18, instead of a 35 profile. The 215/45R18 is 1.3% taller than stock. You may have trouble with the tire contacting the fender liners at full compression. Anyone else run this size?

--Dan
Mach V

 

Dan, I'm going to be running NM springs on Koni Yellows. I was pretty sold on the Ventus V12s and they don't make them in a 225/35/18.

If I would have gone with 17s, the 215/45/17 had a diameter of 24.6". The 215/40/18 has a diameter of 24.8". I wonder if that is too tall of a tire.

Why would someone pick a higher offset versus a lower one? I assume you bring the wheel in as close as possible to the strut with the higher offset in order to run the widest rubber that you can, correct?

The 215/40/18 Ventus is 8.6" wide. How wide are your 225/35/18s?

I love the stance of your car by the way.

 

Generally speaking, you want the offset to be as close as possible to stock, to keep handling and steering feel the same. As you go with wider and wider tires, you may have to move the offset out (lower), but with lower offset comes more chance of running the tire into the fender.

I don't know. The tire pictured is a Sumitomo HTR-4, I think.


Thanks! It's on our own Mach V Technic springs.

--Dan
Mach V

 

So what is stock offset anyways? So now I have one vote that says 40 and another that says 45... I'm not confused at all.

 

As a general rule the OEM offset is dependent on the width of the rim.

The below is from the Mini2 site:
http://www.mini2.com/forum/faq.php?f...heel_tire_tech

15 inch wheels= 45 offset
16 inch wheels= 48 offset
17 inch wheels= 48 offset
18 inch wheels= 52 offset

Hope this helps...

 

Although I know this is true...I'm not sure why. That is, wheel/tire diameter shouldn't really change ideal offset. Anyway, I'd go with 48mm offset as ideal, assuming there was clearance. Usually you take what you can get with aftermarket wheels. Most are lower offset than +48.

--Dan
Mach V

 

I have one more question then. If a stock 18" wheel has an offset of 52 and there are no clearance issues, then why would there be a concern that an aftermarket 18" wheel with a 45 offset would have clearance issues?

 

Because the aftermarket wheel is wider. The stock one is 18x7". The MC wheel we sell is 18x8".

--Dan
Mach V

 

Thanks Dan and everyone else, you've been very helpful. Can I ask one more potentially dumb question...

If I chose the +45 and found that there were inner clearance issues, would adding a 5mm spacer be the equivalent of having chosen the +40 in the first place or does it not work that way?

 

That's exactly how it works.

--Dan
Mach V

 

Thank you again! Looking at some of your other threads Dan it seems like you've tried quite a few aggressive wheel setups which have looked awesome.

I think the 215/40 will give a little bit of stretch while the taller sidewall will still provide a bit of forgiveness on crappy Canadian roads.

I'll probably go with the +40 to push the wheel out closer to the arches to give it a more aggressive look (well at least I hope that's how it ends up looking).

Thanks again for your help. Just curious but are you ever going to get those Rota MCs in stock in 18" again?

 

From what I have seen in previous NAM threads, the offset range is 38-50mm. As mentioned here and elsewhere, 45mm is what the stock rims shoot for. I am not sure how that applies to a given wheel height, but I would think this range is good for 15-17" rims. The only MINI to come with 18s stock is the GP, and very few have attempted to cram 19s on theirs.

You should only need spacers if you lower your MINI with an aftermarket coil-over setup or when using lowering springs on a set of stock struts. However, I have also read you can opt to use the spacers on the front and/or back to help with oversteer and understeer.

For comparison, my old '02 MCS had 17" BBS RK rims, 42mm offset, combined with a set of KW coilovers. It was dropped 1" or so below stock (these were already on when purchased, as it was a dealer demo). The front wheels had 13mm H&R spacers. Additionally, I had to buy 205/40/R17s (as opposed to the stock 205/45/R17s), as the previous owner (a friend) said the inner tire walls would rub the coil-over springs (probably only occurred when the wheels were full left or full right in a turn).