Thursday, November 17, 2005 - 10:56 am, by: David Vaughan(Davidv)
Instead of conjecture, let us try the Society of American Engineers' publication "Tyres, Suspension and Handling" by John Dixon or "Race Car Vehicle Dynamics by W & D Milliken, published also by the SAE. There you will find that the effective camber in steer and therefore camber thrust (sideways thrust from an angled or bumpy surface) is affected by kingpin inclination which is normally designed so the axis runs through the centre of the contact patch (centrepoint steering). By using the wrong offset you separate the centre of the contact patch from the kingpin axis (defining the scrub radius) and introduce steering torque on bumps or road surface changes i.e. "tramlining"
Therefore, all low offset wheel setups (lower than designed) will handle badly.
Thursday, November 17, 2005 - 12:04 pm, by: Dominik Bloemhard(Dominik)
Ok, I guess that answers the question of why its so illegal to change offsets in your car! And the theory sounds very logical (i aint gonna argue with a bunch of engineers and suspension designers LOL!)!
But i would like to say one thing... I had +32 offset wheels on my Soarer and they didnt tramline one tiny little bit. I could have steered with my little finger resting on the wheel (though probably not very safe regardless of offset). Maybe not as extreme as +17, but I think in the real world there are probably many more factors at play which will affect the handling characteristics. Offset is one of, but not the ONLY factor in this - thats why you hear of people with perfect offset wheels still complaining about tramlining...
So the handling may not be ideal (going by your explanation above), but depending on other factors it could be better than other soarers with worn bushes, less than perfect shock absorbers, cheap tyres etc.
Friday, November 18, 2005 - 12:52 am, by: Dominik Bloemhard(Dominik)
I'll probably get flamed by the wowsers, but to fit those wheels you should look at 245/35s or 255/35s. Should stretch nicely on those wheels; It'll be quite stretched, but not ridiculous. And probably not too much. It gets bad when you are looking for tyres to fit 13" wide rims. Even cheap stretched tyres are more than $400 each
Friday, November 18, 2005 - 09:21 am, by: Dominik Bloemhard(Dominik)
Benny, it is definitely horses for courses. The Soarer at the back has very similar tyre fitments (245 on a 10" is similar to a 255 on a 10.5", and 245 on a 10" would be basically the same). A few people already commented on how sexy those wheels looked so i guess I'm not the only one (much like i am sure that you are not the only one who thinks it looks stupid!)
Congrats Ryan, They would look insane on your car and it would make it a very unique soarer!