Okay so I'm at the point where I would like to purchase new wheels and tires.

Currently King Koopa's shoes are the s-heavies with pirelli's 205x45x17. I found a nice set of 5 spoke black wheels on ebay with Kumho Ecsta AST's 205x40x17 tires for a great price.

My only concern is how much the ride difference will be. I know there will definitely be a difference with the wheels only being 17lbs a piece but with a 205x40 tire, how does that compare to a 205x45.

King Koopa is strickly a street car but I would like it to perform as best as possible. Will the 205x40's be a huge difference than the 205x45's? I live in Northern New Jersey so roads are a problem here. In the future I do plan on adding FSD's but I would like new wheels and tires first. Should I just stick with 205x45 tires?

Any and all input is appreaciated as always. Thanks in advanced!

 

205/40's are fine. They will lower that ride height of the car a little because the sidewalls are lower. I had 205/40/17 toyo proxes4 and they were great. But I moved back to 45 for the sidewall. I wanted just a bit more to cushion me from potholes and bad roads. But if the price is right I would say go for it. If you don't like them you can always get a new set of rubber when those wear out.

 

on 205/40/17 before I h&r Springs.

 

mmm those look nice. are those the pro race 1.2's?

edit, nevermind, just saw it in your sig.

 

Ride difference is not your only concern.

205/40-17 has a max load rating of 1102 pounds 23.5" outer tire diam $53
205/45-17 has a max load rating of 1235 pounds 24.3" outer tire diam $70

If you often carry four people in your MINI or need the odometer and speedometer to be accurate then the stock sized 205/45-17 tire size is better. Many of the older tires in 205/40-17 were even less on load rating and unusable for the MINI. Prices are significantly different.

40 series tires will be quite a bit more harsh riding than 45 series. Some additional noise and some added risk to your rims and suspension if you hit a pothole at speed. If you do long commutes the 205/45-17 is easier to live with.