Tyre advice please

[DAZZA]

What would give a lower profile on the following -

 

165/55/13 or 175/50/13 on a 5.5

 

and

 

185/55/13 or 195/50/13 on a 7.5

 

 

I know its all to do with width to profile ratio and I dont think theres much in it, but would like opinions before the wallet comes out.

[danny69]

In both examples the 50 profile will have a profile about 3mm less than the 55.

Not really noticeable probably.

[Stu_B]

What would give a lower profile on the following -

 

165/55/13 or 175/50/13 on a 5.5

 

and

 

185/55/13 or 195/50/13 on a 7.5

 

 

I know its all to do with width to profile ratio and I dont think theres much in it, but would like opinions before the wallet comes out.

 

Well 5.5" is 139.7mm.

 

So a 165mm wide tyre with a 55 profile gives 90.75mm sidewall.

 

A 195mm with a 50 profile gives a 97.5mm sidewall.

 

7.5" is 190.5mm

 

So a 185mm wide tyre with a 55 profile gives 101.75mm sidewall

 

A 195mm wide tyre with a 50 profile gives 97.5mm.

 

Obviously you need to take stretch & bulge into it as a 195mm tyre on a 190mm rim will bulge, while a 185mm tyre will not

 

I think I have got confused & got it wrong somewhere along the line, but hey doing sums seemed more interesting than designing road signs at the time

[danny69]

Stooby, you have done the 195 50 twice,

the 175 50 has a tyre wall of 87.5mm

[Stu_B]

[DAZZA]

Carol Vordaman eat your heart out....... Well done fella's, dont want to much side wall bulge and for the sake of 3mm i'll go the narrower tyre.

 

Thanks again