Re: tire size/stock rim - in response to Stewart

[Peter Loron <peterl@cnw.com>]

Actually the second part of the designation is the height of each sidewall
expressed as an aspect ratio of width to height. For example, if you have
a 205/50 VR 15, the tire is 205mm wide, has 102.5mm (205 * 0.50) sidewalls
and fits on a 15" rim.

Therefore, as your tire width changes, your sidewall height changes in
direct proportion as long as the aspect ratio stays the same.

-Pete


On Thu, 29 Oct 1998, Eric Wang wrote:

> Stewart,
> 
>      With all due respect, I think you've got it all mixed up.  The 
> 205/215/195 etc. designation refers to the width of the tire, not the 
> height.  The 55/50/45/40 etc. designation refers to the "height" (i.e. 
> profile).  
> 
> You wrote "If you want better handling with your current rim, try 195's 
> (i think).  This will, however, make your car look like it has donuts 
> for wheels."
> 
>      If you keep a 15" rim and switch to 195's, keeping the height of 
> the tire the same, they will just look really thin from behind, but they 
> won't look greatly different from the side (i.e. they'll be almost as 
> tall as the 205's).  I don't see how 195's will make the wheels look 
> like "donuts."
> 
>      Here's the bottom of it (from what I understand):
> 
> A 215/55 tire is wider than a 205/55, which is wider than a 195/55.  A 
> 215/55 will be slightly taller than a 205/55 (because even though the 
> profile designation is the same, it varies slightly according to the 
> width designation).  Similarly, a 205/55 will be slightly taller than a 
> 195/55.  However, being that the profile designation is the same, the 
> "tallness" difference is negligible.
> 
>      You also wrote, "Oh, and a larger rim provides for more tire tread 
> on the ground, due to a larger diameter."  Not true at all.  The contact 
> patch for a 17" rim / tires vs. the contact patch for 15" rim / tires, 
> with width being constant, is almost the same.  The contact patch varies 
> with width, not height.
> 
> Eric Wang
> 1994 Black Vento VR6 -- Eibach Pro-Kit, Remus cat-back exhaust, Autotech 
> Q-Chip, K&N drop-in filter, Mintex Redbox pads
> 
> 
> ______________________________________________________
> Get Your Private, Free Email at http://www.hotmail.com
> 

Peter Loron                                                  peterl@cnw.com
---------------------------------------------------------------------------
Before the invention of eruptions, lava had to be carried down the mountain
by hand and thrown on the sleeping villagers. This took a lot of time.