tl;dr version :

Can anybody give a first- or second-person "they'll fit fine" or "you will have major rubbing issues" statement on running a stock-suspension R52 on 18x8 +40mm wheels with 235/40-18 or 245/40-18 tires?

OEM 195/55-16s are 24.44" overall diameter, the 235/40 setup is 25.4" (+.96") and the 245/40 setup is 25.72" (+1.28".)

Full version :

I've got an R52 with a stock suspension on 18x8 +40mm Motegi SP10s currently wearing 215/35 Eagle F1s. Those are ~ .5" smaller overall diameter than OEM, and there is a pretty sizable gap between the wheels and the wells/fender line.

I've never really liked the look of that gap, or the look of the 215/35s on the 8" rims - they look totally streched, and they don't do jack-diddly to protect the rims. And there are VERY limited brands/models to choose from anymore in 215/35-18s, so I'm definitely going wider.

I'm looking at the "Extreme Summer Performance" category because :

• I've got lots of power - pretty much Madness "Stage 4" (minus the header & intercooler), and the Eagles barely hang on at anything > ~ 80% throttle in 1st or 2nd.
• I have a set of 195/55-16 Blizzak LM60s on the OEM wheels for the cold/wet season (I spend 95% of the cold/wet season at < 60% throttle.)
• I don't autocross or track and I typically rack up < 3k miles during the non-cold/wet season, so not super worried about treadlife - if I get two seasons out of them, I'll be OK with that.
• Tread noise isn't really a concern, since it is a noisy-to-begin-with convertible.

Top-dog in the "Extreme" category seems to be the BFGoodrich G-Force Rivals, but the smallest 18" size those come in is the 245/40-18 @ 25.72" (OEM+1.28".)

Next choice would be 235/40-18 Potenza RE-71Rs @ 25.4" (OEM+0.96".)

After that, it is going down to the 225/40-18 Potenzas @ 25.09" (+0.65"), but then I think I'd rather go down to the "Max" rather than "Extreme" category and get some 245/35-18 Pilot Super Sports @ 24.75" (OEM+0.31".)

(as an aside... anybody have any idea why NONE of the "Extreme Summer" category shoes are available in a 35-series???)

aTdHvAaNnKcSe

- z

 

I have fit a 235/40R17 with no issues, but in 18" I'd be concerned the combination of width and diameter could cause rubbing. 245/40 would further exaggerate the possibility of rubbing.

225/40R18 offers the extreme performance tires your after. The consensus is that this size fits fine on the new 5 lug mini's. I have had occasion accounts of rubbing on the older cars. Some say yes they rub others claim to have no issues.

25" tall diameters are very common, so that's why you see less in the 35 series for extreme performance tires. It's all based on the target vehicle's sizing requirements for the line of tires.

 

Hi Alex,

Thanks for replying! A few more questions...

- with the 245/40s, where would the rubbing most likely be an issue? And is it relatively easily addressed by trimming?

- would the 245/35 Pilot Super Sports @ 24.75" (OEM+0.31") be a reasonably "safe" choice?

- for standing-start acceleration and FWD accelerating while turning (with a Quaife LSD), are the G-Force Rivals or RE-71Rs "much" or "marginally" better than the old reliable Pilot Super Sports?

- any downside to squeezing a 245 onto an 8" wide wheel?

Thanks again!

regards

- Zach