I recently upgraded from 16" lusso wheels to 18" wheels. Problem is since upgrading the steering wheels feels heavy. Is that normal or is there a issue. Also has anyone else encountered any other issues that I should be aware of?? Anything will help thanks.
That is a huge increase in tyre rubber - 205/55/16 to 225/40/18
At least four things are happening:
1 New tyres. These are running 7mm or more of fresh tread. Your old tyres were probably part worn.
2 More rubber to drag over the tarmac. A lot more rubber. Friction is at least 10% (and probably 20% higher)
3 Shorter and stiffer sidewalls to resist turning. The old soggy walls made you think you were turning easier, but at first you are just flexing the taller sidewalls. Now you are directly scrubbing rubber on the road.
4 More rotating mass (in the rims and tyres) and it is further from the axis of rotation, all making for a way bigger 'gyroscope effect'. This actively resists your turning the wheels at speed.
The good news?
- better high speed stability
- better braking
- better cornering grip
- faster response to steering input / more agile
The bad news?
- fuel economy
- cost of rubber and rims
- need to join a gym and pump iron?
i would also add worse acceleration to bad news due to heavier tyres and rims (unsprung mass) unless you bought ultra light high performance forged rims and and reduced overall weight of tyre/wheel combo
Yep, I went from 17 to 18 and although the change is less noticeable there is definitely a difference and it is most telling in the mpg stakes. With hindsight, given the choice now I think I'd probably stick with the 17's and see if my insurance company would agree to me running 205/50/17's which I think could possibly be the tyre the Giulietta should run on. People reckon that the grip with 16's is just the same but just a bit squidgy - 17's sort that. Narrower, lighter tyre would improve mpg, braking & acceleration.
Thing is did Alfa fit 225/45/17's because of the cost or because it really needed the extra 20mm of width??