Hi I have a 1988 Skoda Estelle 105 Lux and I was wondering will it run off unleaded, or will i need to put a lead replacment additive in each tank?

The workshop manual I have is dated August 1987 and states the current range of cars is not suitable for continuous use with unleaded fuel. However unleaded fuel can be used under the following conditions:

1 if one tank of fuel is used for every tank of unleaded fuel then no alterations are needed to the service schedule or the vehicle.

2 if any greater proportion of unleaded fuel is used then the service intervals for the adjustment of the valve clearance must be reduced to every 3000 miles.

3 Unleaded fuel may be used on condition that a minimum of one tank of leaded fuel is used for every 1700 miles or 3000km. This is equivalent to one tank of leaded fuel for every four tanks of unleaded fuel. This proportion should not be exceeded. In addition part 2 above should be observed.

I don't know if this changed for 1988 and the later rear engined cars - because obviously at this time it was being brought to their attention about the problems of unleaded fuel.

Did they ever fit hardened seats to the last of the iron head cars?

The octane requirements are interesting too. The 105L and SP and the 120L and GL only require a minimum of 90 octane.

Do the Estelle 105 and 120(G)L run lower CRs than the 120GLS and 130s?