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1955 tbird 

I found an adjustable can from RockAuto.com and it's a night and day difference than the one that came on the Cardone distributor. I adjusted the Cardone to its loosest setting and could barely get the arm to move. I could move it with finger but it was still very tight and crunchy feeling. The new Standard part #VC221 takes little vacuum to move and it is adjustable and smooth.

1955 tbird 

Glad you got the cans work for you - interesting that there must be more than one socket screw size in them. Now that you have the equipment - beware that the can is "active" at part throttle cruise - so long as the engine is producing vacuum - the can is adding advance.
  
This chart comes in some of the replacement can boxes - gives you some indication of what you have to work with. By using a "live" vacuum port off your engine (and a vacuum gage) - at idle - you can test different settings by taking a look at a timing tape on the damper. Simply by pulling the hose on and off the nipple you should see the result at .....say 15 inches Hg. (idle). Those who drive (or have driven) with a vacuum gage to monitor fuel economy will vouch for the amount of vacuum you can see while traveling at road speed.

 
 Steve Metzger       Tucson, Arizona

Thanks for the good info Steve ! , as it turns out the new vac can is going to need some mods since the arm has a different angle than the original, looks like I
will have to relieve the distributor housing slot a little and bend the arm...... Brett

1955 tbird 

The vacuum advance made for the 1957 FEK 12131-B distributor, the inlet end does have a removable end and inner workings. These advances can be bought new, however, they do not come with the removable parts. I have one that does not have the missing parts and have been looking for them with no luck so far. Can anyone tell me where they can be purchased? It does not make much sense for them to be sold new with missing integral parts and there not be a readily available source for them. Any help here would be appreciated.

if the vac can has a straight arm,it is incorrect. should have some fancy bends,also your carb won't match the list. you can modify it re a post on how to do this,or get a 57 carb. I would tend to return the whole thing if it came with the vacume unit.. or did you install the vacuum unit.