107 tyre pressures

[noblemac]

My 1984 280SL is fitted with non-standard 15" wheels and 205/65/15 Pirelli P6000 tyres. I would be grateful for any feedback re the sort of tyre pressures others have found best. NM

 

[Roger Jones]

What does it say on the fuel filler cap or, if not there, the handbook? Depart from MB's specifications at your peril.

 

[popuptoaster]

The way I was told to find your correct tyre pressures for non standard applications is as follows:

Set your tyre pressures at that recommended for standard wheel and tyres.

Drive at your normal speeds for the road conditions until the tyres at at operating temperatures (30 mins around town or 15 mins high speed motorway) stop and take tyre pressures immediately.

If they are more than 10% higher then you need to increase the pressure when cold and repeat.

If they are less than 10% higher then you need to reduce the pressure when cold and repeat.

 

[noblemac]

Thanks.......Yes I know there are figures by the fuel cap but they will relate to standard 14" wheels/tyres. I seem to recall that these cars eventually had 15" wheels as standard (post 1985 'facelift' ? ). That may be the place to look I suppose. NM

 

[wobbly]

The recommended pressures for 205/65/15 are 29 psi front 35 psi rear.

 

[Dieselman]

The way I was told to find your correct tyre pressures for non standard applications is as follows:

Set your tyre pressures at that recommended for standard wheel and tyres.

Drive at your normal speeds for the road conditions until the tyres at at operating temperatures (30 mins around town or 15 mins high speed motorway) stop and take tyre pressures immediately.

If they are more than 10% higher then you need to increase the pressure when cold and repeat.

If they are less than 10% higher then you need to reduce the pressure when cold and repeat.

That's a good method, I read a rise of 4 degrees C was right.

Another method is to draw a chalk/crayon line across the tread and observe how it wears. If centrally the pressure is too high, if at the edges it's too low.