another post re the rover 90 classic

[400+bhp]

what fuel mix should be used now she will be back on the road, unleaded but what octain additive please and what would be the effect of no additive for a short run ?? again she is a 1958 rover 90 thanks again

[tonys]

http://www.roverp4.com/unleaded.htm

Any help?

[john2443]

For a short run, no damage to the engine. Eventually you might get valve seat recession, but that would probably take a few thousand miles before doing any serious damage.

[davepoth]

john2443 said:

For a short run, no damage to the engine. Eventually you might get valve seat recession, but that would probably take a few thousand miles before doing any serious damage.

Several tens of of thousands of motorway miles, says BMW. In fact they figured that the engine would need to come apart for work anyway before the valve seat recession became an issue.