Date: Sat, 28 Apr 2007 17:40:22 GMT From: johannes <johsnospamnospam-efitter.com> Subject: Re: Classic 900 - aluminum or steel/best tires for sport driving
Elder wrote: > > In article <4632E20B.6FEC3026nospamnospam-efitter.com>, johsnospamnospam- > efitter.com says... > > > >I can't see why there should be any difference in performance. But > >changing the wheel diameter for e.g. low profile might change the > >gearing and the perceived performance on the speedo. It will of > >course also improve the handling. Performance drivers usually > >like a lower gearing. (though I prefer relaxed long gearing) > > > Saab made a big thing at the time that the aero 3 spokes (and the aero > body kit) made a difference to top speed because of aerodynamics (not > weight), compared to a steel or standard alloy shod car with no kit. > > I would suggest looking for a set of 16" 9000 Aero 3 spokes for the > summer on a later 900, with decent tires on, and fit winter tyres to a > set of 15" steels for when the weather is less clement (and/or if they > salt the roads locally to you). Depending on the weather extremes where > you plan to travel, you might find two sets of all season tyres in the > different sizes/profiles/widths might be better than a set of wide > sticky summer and narrow soft winter tyres > -- > Carl Robson > Audio stream: http://www.bouncing-czechs.com:8000/samtest > Homepage: http://www.bouncing-czechs.com > Now Playing at home:Front Line Assembly-A Decade > http://www.myspace.com/theelderuk > I have the 16" 3 spoke aero wheels on my 9000 and they do look bloody nice. I jumped on the opportunity to buy them when a saab dealer cleared out some stock. They don't fit on newer saabs as they switched from 4 nuts to 5. However, about the science, I still think it is mostly marketing speak. The 3 spoke wheel was obviously a convenient symbol of the turbo. There was marketing talk that they helped cooling the disc brakes. But wait a minute here: Suppose that a 'turbo' wheel on the right side is blowing into the disc when the car is moving forward. Then imagine taking off the wheel, while still spinning and blowing air towards the back side of the wheel. Then take the same wheel to the left side of the car (wheel still spinning). Mount the wheel on the left side (wheel still spinning). Which direction will it now roll on the car? To perform the disc cooling function, it will obviously have to roll backwards on the left :-) Hence right and left side 3 spoke alloys would have to be mirrors of each other.
