Hello, I Have a 545i sports package that had 8x18- et 20, (245/40/18) front and 9x18 et 32, (275/35/18) rear. I upgraded to 8.5x20 et 18 (245-35-20) front and 9.5x20 et 18 (275-30-20) rear. Looks awesome but the handling of the car is not as tight as before. What an I do to improve the handling ? Perhaps spacers? would appreciate your guidance. Thanks

 

Are you using different tires? Could it be due to the additional weight of the 20s?

 

I'm using ventus v12 evos tires. I don't think the miros are heavier than the stock wheels.

 

what do you mean by tight? going for 18 to 20" you lost quite a bit of sidewall, could this be what you're feeling?

michael
acute performance

 

I would assume "not as tight" translates into it doesn't respond as quickly as the stock set-up when cornering? If so, I notice the same thing with my 19's and the same Hankook tires...the car seems to not respond as quickly when cornering or jerking the steering wheel quickly.
I'm thinking it's just the difference between non runflat tires vs the oem runflats. Their sidewalls were so much stiffer, which translates into quicker responsiveness. That's what I'm guessing anyways. My oem set-up was heavier than my new set-up so it's not a weight issue

 

What happens when you lose side wall?

 

That's it. But I also notice that when cornering, the rear of the car would skid and this didn't happen with my stock rims which didn't even have the run flats. What would explain this, do you think?
Thanks

 

I think you just have a softer tire sidewall with the Hankooks. This would make the body roll more pronounced.


When you "lose sidewall", your tires might feel like the sidewalls "collapse" easily (at least I think, that's what Michael meant) under heavy cornering. This may also be the culprit. Either way, a little over-pumping might fix the issue. What tire pressures are you running?

 

It appears to me that too little side wall will not ?give? enough when the tires are at the limit. With a little more sidewall, if the tires have to grip abruptly the side wall will ?give a little? without breaking traction, with little or no side wall there is no ?give? so the tire will break traction easier and slide easier at the limit. There is a point of no return and to me everyday performance tire technology is at the limit for cornering at the 18 maybe 19 inch area. Tires for 20 inch on up wheels may look great but for cornering it is not there yet, at least compared to the smaller sizes

 

Thanks man, that is a great explanation. Makes perfect sense.