[TR] Grade of Gasoline

[Randall]

> When I had the engine rebuilt they made a change to the 
> valves to accommodate unleaded gasoline.

So it's stock otherwise (83mm liners) ?  Then regular unleaded should do.
If you've converted to the popular 87mm liners, it would likely be happier
with premium (though you might still get by with regular).  Most other
modifications (like shaving the head) will likely require premium.

Either way, be sure to check the spark advance by the method given in the
book.  Full throttle at low rpm in 4th gear and adjust so you can just
barely hear the knock.  Personally I like to back off 2 degrees from that
point, but the book doesn't say to back off.

Randall