all true. The bbk argument is more for going with a 17" verses a smaller diameter. I have a rear seat delete and oz wheels now and my weight sans driver is 2700 lb. if I ever get around to upgrading my stock brakes i'd just go for forged calipers and floating rotors with good pads. Even then it would be overkill for my random jaunts to the track. It sure would look sexy though

yep, just not as good of a track tire selection and more expensive with the 18s.

 

Yup, most BBKs I think people do for the looks more than anything. Which is totally fine - they also provide an interesting feel on the street that can be pretty confident and nice. If you're really going full on track route, my guess is it would be better to stay with 16s, use the gearing from it, and try to get some sort of ducting in to the barkes.

For AutoX, I'd try to keep to 15 even. At that weight, you don't need much tire and you don't need much brake, but lightness always helps.

 

Interesting and I probably should post in a separate thread as we are high jacking randomquickness' thread.

I am no expert but AX seems to be all about better traction and getting as wide of a tire as possible. To my I would think going to 18 and getting a wider tire with a little extra weight would be better than narrower lighter setup. Then again I am still a newb at AX.

 

Nothing stopping you from doing a low profile 15x8 setup. Will be much lighter than an 18x8, and effectively give you a gear ratio for better torque. It will matter even more on a track, where you're unlikely to ever use 6th, and 5th may even be crappy. If you drop that circumference down, you have more usable gearing.

AutoX can go either way - I haven't done it with the Mini, sometimes going too low will make you top out 2nd and have to go between 2/3 too much and cost you time. It's always an experiment, sometimes you need to change it for different courses even.

Lighter always wins though, and all other things being equal, a 15x8 will always be lighter than a 17x8 or 18x8.