AS-20 vacuum can
Thread Starter
Racer
Joined: Sep 2011
Posts: 414
Likes: 55
From: Humboldt county Ca
AS-20 vacuum can
Got one on my bench. Checked it with a mity vac. About 8lb starting and all done by 14.
Can't find info on line for this number and no wrenches seem to turn an adjuster so I don't think it's an adjustable.
Wondering if it's made this way or shot.
All my distributors are HEI and it came out of one of those 3.
Thanks
Can't find info on line for this number and no wrenches seem to turn an adjuster so I don't think it's an adjustable.
Wondering if it's made this way or shot.
All my distributors are HEI and it came out of one of those 3.
Thanks
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
I remember when I purchased a adjustable Vac Can, the instructions stated not to turn the allen screw all the way out or damage will occur. If you can't feel a allen screw through the port with a wrench, its a std, non-adj unit or broke, which I doubt. As far as I know, adjustable units were after-market add-ons.
At one time, Lars had a complete list of GM Vac Cans on this forum with part numbers. Maybe that AS-20 was on there.
At one time, Lars had a complete list of GM Vac Cans on this forum with part numbers. Maybe that AS-20 was on there.
Last edited by HeadsU.P.; Nov 9, 2018 at 06:55 PM.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
Got one on my bench. Checked it with a mity vac. About 8lb starting and all done by 14.
Can't find info on line for this number and no wrenches seem to turn an adjuster so I don't think it's an adjustable.
Wondering if it's made this way or shot.
All my distributors are HEI and it came out of one of those 3.
Thanks
Can't find info on line for this number and no wrenches seem to turn an adjuster so I don't think it's an adjustable.
Wondering if it's made this way or shot.
All my distributors are HEI and it came out of one of those 3.
Thanks
Lars
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Perhaps that's why somebody came up with that bracket that limits the Vac adv. It installs under one of the canister screws, has four options for max adv by simply flipping the unit around. I believe I got mine from Mr. Gasket. Years ago, if memory serves me, I believe the bracket came with a MSD StreetFire. I still use it today on another dizzy with the notch set at 10-13 degrees limit position. Somebody sells those limiter brackets. Don't know who / where.
Currently not running a Adj-Vac-Can but was considering switching to one, sitting on the work bench.
Currently not running a Adj-Vac-Can but was considering switching to one, sitting on the work bench.
Last edited by HeadsU.P.; Nov 10, 2018 at 10:51 AM.
Thread Starter
Racer
Joined: Sep 2011
Posts: 414
Likes: 55
From: Humboldt county Ca
Thanks to all for figuring this out. I'm putting on a AR12 but decided to bench test all the junk I've got rolling around in my parts pile. Strange thing about this unit is that I can't find an adjuster and at full pump the rod moves just over 1/8". It's going in the trash anyhow. Got to thin a few hundred pounds of crap out of the garage.
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