Im looking to buy some new wheels but im not sure weather to stick with 18"s or go bigger and get 19"s. Can anyone help? and if so which width is best and tyres for 18"s and 19"s.

 

thankx, Hanksy

Im looking to buy some new wheels but im not sure weather to stick with 18"s or go bigger and get 19"s. Can anyone help? and if so which width is best and tyres for 18"s and 19"s.

 

thankx, Hanksy

 

My favourite apine headgear situation...

 

The suspension geometry is designed around a particular rolling radius, so it's vital you keep to that spec to preserve handling. In other words, if you make the middle of the wheel bigger you have to make the tyre walls smaller. (And if you don't do that your speedo will under-read and you'll lose a bit of torque at the wheels too.)

 

The difficulty is that 225/45/R16 is equivalent to 225/35R18 or 245/35/R17, is equivalent to, erm... well, can't find a conversion, but it must be about /25 tyres for a 19. Good luck with sourcing those - and you'll need even better luck trying to drive on them on anything other than a motorway.

 

For wider tyres eg 245s you can see the profile required is a bit higher, so you could possibly find some 265s to fit 19s - but then if you fit 265s on the front you'll be well into tramlining territory.

 

Obviously there's a bit of tolerance in all this, and most people don't drive anywhere near the limits of a Z's handling, so some people have done it, but YMMV.

 

Also remember that the wider / lower profile the tyre the worse they are in the wet, and the more NVH you will have.

 

See also the FAQ in the bodywork section!