Donor Tyre Sizes

[Guest graham dockerill]

Getting paranoid about SVA now. My donor was a 2litre 1984 base saloon, but I want to know which tryes were fitted on this model so I can check the tyre bible for comparison. My 2B has a 3.62 diff and 195/50 x 15 tyres on RH alloys. I,ve also got a set of 185/65 x 14 sierra wheels off a H reg 2 litre. Also can anyone clarify that the speedo can show a % over but not under a certain speed. regards Graham

[Joel]

My donor wheels were 185/70/13 from a 1987 2.0GL

 

The speedo thing I think is roughly 10%. That is to say your actual speed can't be more than the speedo reading, but can be up to 10% less.

[Joel]

This is a bit more precise:

 

Speedometers:

1. The vehicle shall be fitted with a speedometer capable of indicating speed in mph at all speeds up to the design speed of the vehicle and capable of being read by the driver at all times of the day or night.

 

2. For all true speeds up to the design speed of the vehicle, the true speed shall not exceed the indicated speed.

 

3. For all true speeds of between 25 mph and 70 mph (or the design speed if lower), the difference between the indicated speed and the true speed shall not exceed:

 

§ V/ 10+ 6.25 mph

 

where V= the true speed of the vehicle in mph.

[Guest graham dockerill]

Thanks Joel, if mine was on 185/70x13 then on my 195/50x15 I should be doing 68.43 mph. So the way I read it, I should be allright ?. regards Graham.