Tyre size question
 

I bought a 1990 240 wagon a couple months ago to replace my beloved 940. Still have the 940, but it's soon headed to the junkyard, unfortunately, as it was rear ended last fall. I've been over at the 700/900 side of the forum a bit, they are a fabulously helpful bunch.

I've been stripping the 940 for comparable parts to use in the 240, which aren't nearly as many as I expected, however:

The 940 has newish tires 195/65 r15 91h. maybe 4k miles tops on them, still look great.

The 240 has not so newish tires 195/70 r14 91h. Decent amount of tread left, but obviously more wear than the 940s... also, they seem to be of lesser quality.

Any reason I can't flip the two sets? Would that extra inch of radius be problematic? I've seen some stuff about performance differences, but haven't found anything conclusive.

Your speedo will read a little higher, not a major issue, but primarily the load index must be sufficient and the non std size is a modification so can affect or void insurance if the company see fit.

Basically, all of the 240/700/900 series wheels are interchangeable except for the very last V90 and S90, these use a FWD type wheel. Your 940 wheels will be good on the 240 if you like the style. That can be a major issue for some people but in this case, economics may be the overriding factor.

Zlornick

I fitted Volvo Rigels (alloys) on my 240 shod with 195/65/15 tyres - off a 760

so far as I know 240s came with 14 inch steels and 15 inch alloys (and maybe earlier ones had other variations)

If you think about it, it's not the wheel size that really matters, it's the tyre aspect ratio. Your 240 tyres have taller walls than the 940 tyres (70% vs 65%). The change may very marginally affect the gearing/speedo reading and they will also affect the ride quality

There are loads of web resources where you can punch in different tyre widths, heights and wheel diameters to see what difference it makes in terms of gearing/speedo reading as well as looks

Should be no issues. good luck

Sh1t!!
I didnt notice the wheel diameters differed!
Yes 195/65 r15 is correct changing from 195/70 r14, so thats all good!

Ahh...That makes sense.

I think I now understand the "aspect ratio" portion of the sizing nomenclature. A bit misleading, to be honest.

Thanks for the input.

Zlornick

As I understand it: 70% (for example) means that the tyre wall height is 70% of the tyre width. So if a tyre is 195mm wide, then the wall is 70% of that, in other words 136.5mm high

I agree, it seems an overly complicated way of expressing the relationship between width and height. someone obviously got off on it!

Anyhow. Good luck

That is correct.

Do it!
Personally I prefer the 195/65R15 much over the 195/70R14 on a 240.
I drive this on a 240 and even the larger 205/55R16 on the 700 and 900 series

Have a nice weekend, Kay

Almost completely accurate: apparently Virgos will not fit 940s unless you mill the front brake calipers, but any 940 or 960 wheel will fit a 200-series car, although you may find that the stud on the hub fouls some of the wheel types.

The stud? That locating pin for [some] earlier wheels? It can be unscrewed and replaced with a set screw. :)

The stud (as we are calling it) is there to hold the disc onto the hub with the wheels off and to assist wheel location when changing a wheel for whatever reason

Probably to fit Virgos in the past, the studs on my car have been reduced in length (partly sawn off!!). That too presents no problems and retains their functionality...

I've always understood the "stud" (prong about 3/4" long ?) was there to ensure that the wheel could only be refitted in one position as it had to coincide with a single hole in the wheel.
It used to be possible to get wheels balanced on the car, the balance being lost if the wheel was ever replaced in a different position on the wheel studs. For some reason that doesn't seem to matter now - perhaps hubs and disks are better balanced in manufacture?

That is my understanding Clifford. A locating pin for that time when Jo Public were "persuaded" that balancing needed to be done on the car.

IIRC Videos have an indent on the mounting face that allows them to be properly located over the stud.

It's a long time since I've seen a steel wheel with the extra small hole to align over the stud. In the past I used to drill a small hole in the wheel, but it's easier to cut the stud off, replace it with an ordinary bolt, or just unscrew it and not bother.
Nothing's going to fall off while you change a wheel. :)

Predic[a]tive text
 

The perils of using a mobile phone - "Videos" should, of course, be "Virgos".