240 tyre sizes in modern numbers

jamesinc

In the past I have heard that the tyre sizes found on old 240s aren't directly comparable to modern tyre sizes. Indeed, according to this website, it seems a conversion is necessary.

Band Aid (1981 244 DL sedan) currently runs 185/75R14, however if I convert the manual's 185R14 spec to modern dimensions, I get 205/70R14.

Does that sound about right?

PaddlerEd

185R14 are still available, but mainly as a light truck tyre (185R14C or similar) as they are used on Mazda E2000 vans and a lot of trailers.

Vee_Que

Go backwards from a Virgo, which is 195/60/15?

jamesinc

But is that a Virgo expressed in modern nomenclature or in the old style?

Major Ledfoot

Virgos' tyre size (as long as I've known) have always been expressed as 195/60/15. They were a popular option with new 83/84/85 privately-purchased 240s.

AFAIK, that size chart is handy for 70s stuff, but not really applicable for mid 80s stuff, since the 'modern' scheme was certainly in use during 1982, when I put Cheviot Quattros on the 144. I went down an inch to 195/60/14 since 15 inch wheels would've blown my budget at that time. But I clearly recall the size scheme in common use back then.

Then again, you could always drive at motorway speed on 20+ year old tyres until they violently delaminate, and justify the use of dangerous tyres by saying they don't make that exact size any more, when the modern replacement is 1mm difference in diameter...

jamesinc

I think I'll switch to 195/70R14 then

tbro

OM, 185/14 is actually 185/80/14,
rule of thumb, rough but near enough
as you increase the first number by 10, decrease the second by 5, but remember rim width needs to increase after 3 sizes
185/75/14
195/70/14
205/65/14 (Pirelli only)
215/60/14 (req wider rim)