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Tire Size on E30 325i

          In reference to my search for greater output at low-revs, I am 
          actively pursuing various leads received (btw, thanks to the 
          senders), and will post when I have conclusions.  One of the 
          leads is changing gear ratios (won't increase engine output but 
          may increase acceleration in city driving).
          
          Back to tires, rolling diameters and gear ratios.  Dwayne 
          Paschall mentions to Steve that the 225/45-16 will have a 3.3% 
          greater diameter, and thus rev/mile will be 3.3% lower.  Dwayne 
          assumes 195/60-14 as the base tire.  Isn't 195/65-14 the standard 
          factory tire for the US E30 325i/ic ?  195/60 was the standard 
          tire for US E30s of 1984-85 and some 325 eta of 1986-88 (do not 
          know when the switch from 60 to 65 occurred for eta-engine cars).  
          
          For the 325i, the rolling diameter and speedo reading going from 
          195/65-14 to 225/45-16 would almost not change (less than 0.1%)
          
          Tire size	Diameter      Circumference   Revs/mile	 
          195/65-14	23.980 in.	75.34 in.	841.0
          225/45-16	23.972 in.	75.31 in.	841.3
          
          
          P.S.:  If my comments are wrong, please let me know.  This would 
          be useful to know for the gear ratio change idea.