# direction of vacuum advance can



## kevin1727 (Aug 4, 2021)

I can't get to my distributor advance can to adjust it, and the vacuum hose is pushed against the driver's side head.
Which way is the distributor normally positioned so the air can is in the clear?


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## sameold01 (Jun 21, 2020)

Hey Kevin I have been following your journey the whole way and you have done a great job. On the dizzy can it should be parallel with the firewall so you might want to remove distributor and turn it counterclockwise a tooth or 2.
I would reach out to lemans guy here on the forum for some dizzy help and he had me buy a specific can from oreillys auto. I have built a 461 stroker with a zero deck true 10.75.1 and I am running manifold vacuum. My initial is 18 degrees and he had me buy a specific vacuum can that pulls 12 degree with a limit set. That is 30 degrees of timing at idle which is ok and runs smooth. I have the weights to come in at 2800rpm at 16 mechanical degrees limit which is 34 degrees total timing. My car runs better and cooler hooked to manifold vacuum and hold 180-185 degrees in the heat and fires with just a bump of the key. I do run some 110 added to 90 ethanol free.
I had my dizzy curved on a sun machine and carburetor calibrated by a guy in CT everyday performance. I would rather me personally just send it to the people that know what they do well than spend weeks trying to get it right. I am sure you can fine a person on facebook or the net to recalibrate the carb. I know qjet power is backed up for months. good luck


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## LATECH (Jul 18, 2018)

Good post by same old 
Can is actually in the correct factory postition, as the OE unit had a curved tubed , curving upward from the factory.
Follow what same ol says and you should be good to go
I had the same trouble on my 64 when I installed the adjustable can.


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## CoveKid19 (Nov 18, 2021)

Though it'll work, you really don't need to remove/move the distributor. Much easier/quicker to loosen the clamp, rotate the distributor CCW 1/8th of a turn, move all plug wires 1 hole CW to the right, then re-time.


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## BearGFR (Aug 25, 2008)

Yep, easiest way to solve your problem:

Remove the distributor cap after noting which cap terminal is connected to #1 p[lug wire.
Bump the engine with the starter until the rotor points to where #1 plug wire was connected (when the cap was on).
Loosen the clamp, and turn the distributor body in whichever direction gives you plenty of room for adjustment without the can hitting anything. As best you can, move the body in increments of 1/8 of a turn (the distance between cap terminals). You don't have to be perfect on this because you're going to re-time the engine when you're all done. This just makes things a little easier when you get to that step. 
Reinstall the cap, then move all the wires on the cap so that #1 wire is connected to the terminal that the rotor is pointing to NOW.
Fire it up, reset your timing.
If you have trouble getting it to start after moving everything, move the distributor body "a little" (small increments) until it fires, then set your timing. 
Bear


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## kevin1727 (Aug 4, 2021)

CoveKid19 said:


> Though it'll work, you really don't need to remove/move the distributor. Much easier/quicker to loosen the clamp, rotate the distributor CCW 1/8th of a turn, move all plug wires 1 hole CW to the right, then re-time.


I did this. Worked fine and allowed me to try adjusting the vacuum advance.
The air can is more towards the firewall now. Eventually I'm going to pull the distributor anyway because number one plug is currently pointing towards the glove box.


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## geeteeohguy (Feb 2, 2008)

I bought both a Crane and an Accel adjustable vacuum advance at the same time, one for each car to check them out. Both failed on the first day of use. The instructions said to turn the allen key clockwise until it stops, and then back off for the desired amount of vacuum. In both cases, the allen head stripped and the advance units leaked vacuum. I ended up re-using the 55 year old GM stuff and limiting the arm movement mechanically. Have you guys had better luck with the adjustable vacuum advance cans??


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## armyadarkness (Dec 7, 2020)

My vac can is on the passenger side. Never bothered me.


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## kevin1727 (Aug 4, 2021)

I was thinking about that location too, but it's the same problem with the heater hose coming off the engine. It's only a small angle on either side of the engine where it will be easy to get an allen wrench into the can.
The driver's side may be easiest if I raise the ignition coil.


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## armyadarkness (Dec 7, 2020)

It's not something that requires regular attention, so turn the dizzy, adjust the can, and then turn the dizzy back.


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## lust4speed (Jul 5, 2019)

geeteeohguy said:


> Have you guys had better luck with the adjustable vacuum advance cans??


I've used quite a few of them and haven't had one fail. It's been awhile but I believe that the Crane unit tightens up the complete vacuum advance curve by increasing spring pressure while the Accel unit was a simple internal block that limited total vacuum advance. I found the Crane unit works better because it could be adjusted to slow the vacuum curve while the Accel sometimes brought it in too soon without any way to slow it down. Sometimes with the Accel I'd be fighting a shot of detonation when first tipping in the throttle at cruise with no way to dial it out. Another twist on the Crane would stop the tip-in problem. I would use a limiting hook inside the distributor on the vacuum arm to limit total vacuum advance if it was too much. Except in a few cases where the expensive Crane unit was needed, most of the time I could just install the limiting piece to keep total vacuum timing at about 12°.


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