Date: Fri, 06 Feb 2004 18:55:22 +0000 From: Johannes H Andersen <johsnopsamfitter.com> Subject: Re: 900 wheel size question
**-** wrote: > > "Johannes H Andersen" <johsnopsamfitter.com> wrote in message > news:4023D69E.706E0A61nopsamfitter.com... > > > > > > tom wrote: > > > > > > I (think I) got 16 wheels right now. > > > What is the benefit of getting 17 or 18 wheels. > > > ( '88 900i 8v) thanks, tom > > > > Only cosmetic benefits, but your teeth will fall out. Stick to your > > 16 wheels. > > Well not really theres many benefits other than cosmetics. The main one that > would apply in a road car is that the height of the sidewall is reduced > proportionaly to the size of the wheel, the smaller the sidewall the less > sidewall flex will occur meaning sharper handling and an increased ability > to make it stick during high G/high speed cornering. > > Following on from this under hard braking from speed (think really hard > braking) the 'stiffer' sidewalled thinner (in a radial sense) tyre won't > pool as much as the weight shifts onto the fronts meaning that you able to > brake and steer at the same time more effectively and eliminiate/reduce the > risk of pulling a tyre off the rim if it goes pete tonge. > > A large rolling radius, which can be produced by enlarging the size of the > wheel will also directly impact the final gearing of the car, meaning in the > very simplest terms you can gain top end or increase acceleration by varying > the size of the wheel/tyre combination. > > Going a stage further many wheels designed for race use are made not of > Alluminium alloy but of a Magnesium alloy, they are incredably light, > lighter than the rubber so a larger wheel with a smaller tyre reduces > unsprung weight (note this doesn't apply to halfords range of fetching 'Fox' > wheels ;-)). Take a look at Touring cars with 18' wheels and 30profile > slicks. > > Cheers > Matt I agree that there may be these benefits, but if he started, say with 15", then his 16" (50 profile?) have already a lowered tyre profile and derive some of these benefits, sufficiently IMO. Going still further with yet lower profiles, and the ride might become unacceptably harsh.