I need new tires. My brother had some new Goodyear F1s off his BMW that are pretty much unused (less than 500 miles). They're 205/45/17. Just wanted to verify that they'll fit fine. He said the main difference is that the speedo will read about 2mph slow at 60mph. I know he knows his stuff but I just want a second confirmation.

 

find out yourself by inputting your stock tire size with the new proposed tire size

http://www.1010tires.com/tools/tire-size-calculator

the calculator will let you know if the new proposed tire size will throw off your spedo and by how much, as you have to keep the same rolling diameter as stock.
if the new tires are less than 3% in variance, you're fine and your car will be fine

 

Just make sure you run the same tire size on all the wheels, I had two smaller ones on the front and stock size on the rear, when u got on there throttle the /!\ would blink! when u hit a bump and the wheels spun at a different rate at all! it would go off..

Smaller tire tho all around won't be bad, except you will be using more gas cause ur gears are now smaller due to the smaller circumference of the tires. Car will feel faster tho. More clearance in the wheel wells so if u are low this would make more space for you

 

No traction control on the 6-speed so no worries about the /!\

Didn't think about the gas mileage part. We'll see if it's noticeable.

 

did ya input into the calculator yet?

 

Yeah. Will put the speedo off by about 4mph. No big deal.

 

ive bet those tires are not "safe" for the car. the load rating is too low for the cl. those are probably 87 when the cl needs a 91

 

BMW 330ix weighs more than the CL-S or about the same.

 

why would you run a 205 on any bmw? unless its late 80's lol

 

No but it can mess up the ABS

 

Turns out the tires are the same sidewall, just slightly smaller width. 205/50/17 so I'm just losing less than .5" of width and a touch of height. Variance of 1.57% too slow so it'll only throw the speedo off by about 1mph.