Z4 Autocross Setup

Sirius19 · 03-03-2025, 12:13 PM

Hello everyone, I just recently purchased a Z4 3.0si that I'm going to start autocrossing in the street/stock SCCA class.

The first purchase is going to be a dedicated set of autocross wheels. I can go up or down 1 inch in diameter, so I'm thinking about going with the 17" rims.

The front rims are 8" width and rear ones are 8.5", but I have been reading that keeping the same size tires on front and back is the way to go.

I'm interested in getting feedback about wheel/tire size selection and anything else autocross related. I like the feel of the Bridgestone RE-71RS, so I'll probably stick with that brand.

Sirius19 · 07-25-2025, 12:11 PM

Looks like there are not many Z4 owners autocrossing their car. It's not really competitive versus the Miatas at the national level, but it will surprise you.

I decided to go with 17" rims with Bridgestone RE-71RS installed. 245/40/17 on the front and 255/40/17 tires on the rear wheels. The front tires are slightly pinched, but work for autocross.

I did install Koni Sport shocks/struts. I'm still trying to find the right shock and tire pressure settings. After I get more seat time, I will decide if I need to upgrade one of the sway bars.

03-03-2025, 12:13 PM	#1
Sirius19 Registered 0 Rep 3 Posts Drives: 2007 Z4 Join Date: Feb 2025 Location: Kentucky iTrader: (0)	Z4 Autocross Setup Hello everyone, I just recently purchased a Z4 3.0si that I'm going to start autocrossing in the street/stock SCCA class. The first purchase is going to be a dedicated set of autocross wheels. I can go up or down 1 inch in diameter, so I'm thinking about going with the 17" rims. The front rims are 8" width and rear ones are 8.5", but I have been reading that keeping the same size tires on front and back is the way to go. I'm interested in getting feedback about wheel/tire size selection and anything else autocross related. I like the feel of the Bridgestone RE-71RS, so I'll probably stick with that brand.
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07-25-2025, 12:11 PM	#2
Sirius19 Registered 0 Rep 3 Posts Drives: 2007 Z4 Join Date: Feb 2025 Location: Kentucky iTrader: (0)	Looks like there are not many Z4 owners autocrossing their car. It's not really competitive versus the Miatas at the national level, but it will surprise you. I decided to go with 17" rims with Bridgestone RE-71RS installed. 245/40/17 on the front and 255/40/17 tires on the rear wheels. The front tires are slightly pinched, but work for autocross. I did install Koni Sport shocks/struts. I'm still trying to find the right shock and tire pressure settings. After I get more seat time, I will decide if I need to upgrade one of the sway bars.
	Appreciate 0 Quote