215/40/17
 

Interested to hear others opinions on running a 215/40R17 instead of a 215/45R17.

I realise that the speedo will then be out, and it will also effectively shorten the gearing (a good thing IMO)

Because the sidewall is less, it will also lower the car.

I'm pretty certain I will run a 215/40R17; but am interested in hearing reasons why this may not be a good idea.

FYI My car will be coming with 16" wheels, so I don't have 215/45's that I am replacing. If I had the 215/45's from factory, I probably wouldn't replace them.

The wheels will look too small for the wheel arches. If anything size up a touch to fill them in.

You may gain acceleration from the shorter size, but as stated, you'll have a tiny tire in your wheel wells with 4x4 look even worse (unless if you are lowered). Your car will also be more responsive. But you might gain more road noise and a firmer feel. As you stated, your speedo will be off and may require more shifting depending on your application. Of course this all depends on which tire you go with. Also, in some cases, the shorter tire will be lighter as well. Tire selection for 40's is less than 45's. But they do have some good ones in the 40's.

Seems to be a case of function over flair. I think I'll try it and report back.

:thumbup:

I have 215/40-17 on the front pair of my 17x9 Rotas. I think you might be looking for stocks with that tire size, though.