0

I am a student for automotive and have a print out of the conversion chart for tires. it says I can go from 215/70r15 to 244/55r16 and only lose 1mph on speedometer, but found some 245/50r16 will that be a too much of a conversion?

2
  • how do you figure 5 inches? In any case youll likely have clearance issues.
    – agentp
    Commented Feb 25, 2016 at 2:33
  • 5
    Tyre sizes are width(mm)/profile(percentage)r(in). 245*50% gives 122.5mm tall, 215*70% gives 150mm. Both tyres have a final radius of not quite 21". with Circumference = pi*diameter, I get a grand total of .3" difference. The 217/70r15 is a whole inch narrower than the 245/50r16 though. In short, where are you getting 5" from.
    – Leliel
    Commented Feb 25, 2016 at 3:15

1 Answer 1

1

245/50r16 tyres are 30mm (just over 1") wider than 215/70r15. More of a difference is the diameter - 215/70r15 gives 26.85" or 682 mm, 245/50r16 is 25.65" or 651mm - just over 1", or 4.5% smaller - your speedometer will over-read by nearly 5%.

Also bear in mind that you'll need new wheels for the 16" tyres (though that might be the whole reason you're asking?), so make sure they will fit correctly - check the offset and PCD (bolt pattern) of the new wheels before buying.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .