986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - 20''-22'' inch rims

mikefocke · 02-20-2008, 05:57 AM

You say you live in New York (where the winters are harsh and the roads crappy).

In order to keep the speedometer readouts correct, the overall diameter of the wheel+tire must be the same as stock. (17" wheels were stock, BTW. 18s were options.) so the bigger the diameter of the wheel, the flatter the tire. Which looks great to some people. But hit a bump and imagine what happens. The tire compresses and there is less crush space before the bump contacts the wheel. The result is bent wheels. (Just replaced 3 stock "Mag" wheels last week on my wife's Acura.) Bent wheels can often/sometimes be rebuilt at the cost of time, trouble and $n00s.

So go big wheels and skinny tires and you will get:
- fragile wheels
- poor handling due to mismatched suspension design and wheels/tires.
- an uncomfortable ride
- loads on the suspension parts they weren't designed for (read: repair bills)
- more expensive tires and more $ to mount them.
- more frequent tire replacement
- tires that handle less well in the rain or snow (tread not as deep)
- poor handling under all conditions (suspension wasn't designed for those type tires. Porsche has specific tire sizes and specifications they approve for use with each of their cars so that handling is safe and consistent. Ask at the tire shop about N rated tires for a Porsche.)

and all to achieve a look that announces to those who know cars you know nothing about making a car handle.

I'd suggest you spend your money on a driving school that teaches you to drive the car to its capabilities on a race track. While you are there, ask people there about the best wheel/tire combinations for a Boxster. I'll bet you hear that 18s are the sweet spot and that Carerra wheels are the lightest and give the best handling. But that the stock 17s are fine wheels too. Then take your stock wheels and put good winter tires on them because the best tire for a Boxster are summer only tires, don't drive them in temps where the road surface is going to be under 40 degrees. You will have a 50+% increase in stopping distance not to mention a significant loss in lateral traction if you do.

You asked for an opinion, that is mine.

02-20-2008, 05:57 AM	#15
mikefocke Registered User Join Date: Aug 2005 Location: Sanford NC Posts: 2,583	Dumb idea You say you live in New York (where the winters are harsh and the roads crappy). In order to keep the speedometer readouts correct, the overall diameter of the wheel+tire must be the same as stock. (17" wheels were stock, BTW. 18s were options.) so the bigger the diameter of the wheel, the flatter the tire. Which looks great to some people. But hit a bump and imagine what happens. The tire compresses and there is less crush space before the bump contacts the wheel. The result is bent wheels. (Just replaced 3 stock "Mag" wheels last week on my wife's Acura.) Bent wheels can often/sometimes be rebuilt at the cost of time, trouble and $n00s. So go big wheels and skinny tires and you will get: - fragile wheels - poor handling due to mismatched suspension design and wheels/tires. - an uncomfortable ride - loads on the suspension parts they weren't designed for (read: repair bills) - more expensive tires and more $ to mount them. - more frequent tire replacement - tires that handle less well in the rain or snow (tread not as deep) - poor handling under all conditions (suspension wasn't designed for those type tires. Porsche has specific tire sizes and specifications they approve for use with each of their cars so that handling is safe and consistent. Ask at the tire shop about N rated tires for a Porsche.) and all to achieve a look that announces to those who know cars you know nothing about making a car handle. I'd suggest you spend your money on a driving school that teaches you to drive the car to its capabilities on a race track. While you are there, ask people there about the best wheel/tire combinations for a Boxster. I'll bet you hear that 18s are the sweet spot and that Carerra wheels are the lightest and give the best handling. But that the stock 17s are fine wheels too. Then take your stock wheels and put good winter tires on them because the best tire for a Boxster are summer only tires, don't drive them in temps where the road surface is going to be under 40 degrees. You will have a 50+% increase in stopping distance not to mention a significant loss in lateral traction if you do. You asked for an opinion, that is mine.