Volvo Repair: volvo vacuum advance unit, vacuum advance, vacuum line

Question
hello bilbo
I spoke to you recently about an83  242 volvo dl with a B21 A engine regarding the distributor being conventional with breaker points instead of breakerless. It is a canadian car and definately does have points. The problem now is to get a new vac advance unit. I can get one with a dual diaphram whereas the car had a single diaphram. will the dual one work?  thanks  Don P

Answer
Hey,I guessed it.
      About the distrib...

   Set up your timing light.
  Set the timing to the correct setting.
   rev it up to..maybe 2500rpms...see what your advance is...on your timing...I'm assuming that there might be a advance unit below the points plate...thru centrificale force it advances your dist...if the total advance is 30....you don;t need the vacuum advance unit...i think.
 you might put it in the dist...put vacuum line on different diaphrams...check it out to see what you can do...keeping it to manuf. specs....options relating to advance....and ...retard....are in your hands.

  Good luck
  Bilbo