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DISCOUNT TIRE DIRECT.COM says that you can fit a 225/50R16 on the base vibe. Is this correct...and does it apply to ALL tires this size REGARDLESS OF MANUFACTURER AND SO FORTH...?-PHIL

Stock 16" tires are 205/55-16 and are 24.9" tall and 78.2" in circumference.225/50-16 tires are 24.9" tall and 78.1" in circumference so yes, they will work great.

quote:Stock 16" tires are 205/55-16 and are 24.9" tall and 78.2" in circumference.225/50-16 tires are 24.9" tall and 78.1" in circumference so yes, they will work great.please post the formula to get those numbers.... I used to know it

Easy. Since a 225/50R-16 is 225 mm wide and 1 inch = 25.4 mm then to get that in inches, divide: 225 / 25.4 = 8.858 inches wide.50 means that the sidewall is 50% of the width so multiply 8.858 x .50 and you get 4.429" sidewall height.Since there are 2 sidewalls (one on each side of the wheel) you multiply by 2 and then add the wheel diameter to get the tire diameter: (4.429 x 2) + 16 = 24.858 (round up to 24.9).To get the circumference multiply by PI (3.14159) 24.858 x 3.14159 = 78.0945 (rounded up to 78.1)So the formula is 225 (width) / 50 (% aspect ratio) - 16 (wheel diameter)((((width / 25.4) x % aspect ratio) x 2) + wheel diameter)((((225 / 25.4) x .50) x 2) + 16) = 24.858However, forget formulas, used the web:My favorite: http://www.miata.net/garage/tirecalc.htmlAnother good one: http://www.sgmotorsports.com/tiresize.htm

The only issue here is that the wider tires are being put on the same wheels. Therefore, the section width will only increase by 1/2 of the 20 mm increase. Your section width will be 0.39" shorter than calculated above. Since the aspect ratio is 50% on the proposed tires, you end up 0.39" shorter than stock. This is only 1 1/2%, so it may not be noticable.

Here's another tire calculator like Nova found in the web: http://www.c5-corvette.com/tirecalc.htm