How to adjust adjustable vacuum advance?
 

My HEI distributor has an adjustable vacuum advance unit. How does one go about adjusting it? It has a hexagonal shape. Is it adjusted by rotating the housing? Thanks.

temvette72:cheers:

There is an allen screw inside the vacuum nipple.

Thanks a bunch!

Temvette72:cheers:

OK that's great, but when you turn it, exactly what happens?:thumbs:

I'm only familiar with the adjustable can I had on a points dist. The allen screw controlled the rate and there was a seperate bracket that controlled the total amount the can could advance the timing.

Heres some instructions...

http://69.20.53.62/pdf/210g2.pdf

tonyv123 s post explains it......PITA big time, I dont care for them.

You also need to set the max advance with a limit plate of some sort.
Here is the Crane unit and their instructions.

http://69.20.53.62/pdf/254g.pdf

The easiest way to set the adjustables is using a hand vacuum pump on the cannister to tell you what the vacuum reading is when it opens, and checking with a timing lite.