a tyre question please!

Im looking for new tyres for my mk1 1980 gls auto.

Im confused about the tyre spec for this tyre?

I thought there should be three sets of numbers i.e 195/65 r 14.

on my tyre it shows a size 155 13 78s radial……..now when i do an online search for tyres the search asks for a sidewall size.

Im guessing that 78 is related to the sidewall size? but the michelin site and other sites dont reconise the 78s?

any ideas please

thanks

Lee

155= width
78?… i think this must be 70. = % of width makes for your sidewall size.
13, (R13) = 13 inc wheel.

this site may help, measure the size diameter, you know its 13 and 155, so play untill ypu have the right size.. ish

Tire size calculator

Sounds like an old set of SR tyres there. The markings on these do not specify sidewall height as 155 and 145 SR's came with only opne choise of sidewall height. For reference I think the closest modern tyre size to the originals is 155/80/13.

Cheers

If the tyre spec doesn't have a profile, then its assumed its 80%.

cheers guys!