Wheel size selection, Need some schooling! Options

[KevinP]

I was wondering why someone would want to go to a 17 inch wheel on there 914 from the stock 15 inch.

I now see you have an increase in wheel and tire weight with the increase in size and the chances of have more problems with handling and balance. Are they reducing the difference by going to a low profile tire?

I still see that you have more rotational mass than stock...this i see as a problem or the potiential for.

See if you can edu macate me here............TIA

KP

[woobn8r]

Although the wheel is larger and the sidewall is shorter, the overall circumference should stay just about the same (if done correctly) The overall mass of the wheel tire assembly changes very little.

True, the percentage of weight at the circumference is slightly increased but this is negligeable in performance...and highly out weighed when you consider the performance benefits of the "modern" tires stiff sidewall and casing designs.

You can accomplish the same weight imbalance and stay with OE size wheels by using a light alloy wheel (i.e.Fuchs) and a cheaper offshore tire choice that weighs more than a performance tire. Runflat tires also will change this ratio as they weigh considerably more than a regular performance tire

That is why each wheel tire package should be researched to see if it suits the consumers needs.

Aesthetics, performance and size availability all influence the decision of which combination to use.

Some people choose to alter their gearing by using shorter or taller tires on the same rim....this may give a greater "hole shot" for an autoX or cheat the dyno on an emissions test.

In the end, unless you are racing I wouldn't worry about the % of mass that is on the circumference of your wheel/tire assembly....it simply is too small a factor to worry about....and if you are racing....there are some lightweight tires available.