Kevin Sullivan asks:
> Hmmm. Is the proper octane specified somewhere or did you arrive at 93
> empirically (e.g. timing's right and it knocks with 89) or what? Do you
> have the high compression engine?
The original factory service manual for my '67 MGB makes dire predictions
of what will happen if less than 98 octane gas is run in the engine. I'm
told by people in the know that the way octane ratings is calculated has
changed and that the old 98 octane is the same as the new 93 octane. My
car has the high compression engine as (I'm told) did all of the MG's
imported to the states. Are you sure yours has the low compression engine?
After 16 years and three different engines, I've discovered that my pre-smog
LBC doesn't like low octane gas, especially Arco. With all of the proper
settings, the car runs great and never runs on with 93 octane gas.