Don - Why do you feel that 190°F is over heating? 190°F is about the temperature that the B series engine runs the best (I run a 195°F thermostat in our MGB year around. Remember, an engine is NOT overheating as long as it is not boiling while the car is moving. If you are loosing coolant when the car is stopped and the engine shut off, then you are either overfilling the radiator or you do not have a coolant recovery system (if you want the coolant to stay right at the top of the filler tube) - see the article, Expansion Tanks, Coolant Recovery Systems and How the Cooling System Works in the Other Tech Articles section of my web site at: http://homepages.donobi.net/sufuelpumps/ As for the vacuum advance, the ported vacuum is the original vacuum advance used on the B series engines. I would suggest contacting Jeff Schlemmer at jeff@advanceddistributors.com and check to see if you have the correct vacuum unit on the distributor. If not, I'm sure that Jeff can supply one for you
Cheers,
Dave
http://homepages.donobi.net/sufuelpumps/