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By Talkwrench - 15 Years Ago
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Well my nice recoed Cardone dissy turned up and I though I would try the vacuum advance and see what size allen key it is.. mmm Nothing I put in there is working, it certainly looks like the adjustable type of vac adv but nothing...? Do they reco these and leave the adjustment out? AGHHhhhh!!!
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By Ted - 15 Years Ago
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Adjustable vacuum advance chambers are not available as an across the board item. Depends strictly upon the chamber manufacturer whether they want to make a single distributor advance chamber that covers several applications but requires an adjustment feature for the vacuum advance amount dependant upon the vehicle the chamber is being fitted for. Other manufacturers will make chambers that are specific to the application but requires a larger inventory of different numbers to cover the various applications. The original chambers on the late Fifties Fords simply had a removable nut at the vacuum flange where the springs and/or spacers could be changed out.
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By oldcarmark - 15 Years Ago
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How much advance is it providing as is?(How far does it advance timing when vacuum applied at idle?).Are you sure you tried a small enough Allen key in standard not metric size?Ted may be right but these usually fit several different applications and should provide adjustment via Allen key.
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By Talkwrench - 15 Years Ago
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The dissy is not in, its just sitting on the bench as I am waiting for the 925D springs to arrive, I haven't pulled it apart yet to see what the settings are inside. All I know is with the vac adv no key is fitting I doubt there is anything inside that is adjustable, it certainly looks like it should be its not the old style where you have to had shims and tubes. I guess Im out of luck there. It seems to pull the plate around quite a bit when I suck on it so Im not sure how I am going to adjust it when the time comes?? So suggestions guys.Im going to follow your instructions Mark on how you set yours up...
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By GREENBIRD56 - 15 Years Ago
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Honestly I didn't realize that there were variants of the modern "replacement" vacuum pots that aren't adjustable. It just seemed like every replacement dizzy we found, had instructions about how to make your "new" advance behave like your "old" one (a limiter). Ted is right - cheap may be the ruling factor for some of the rebuilts. Just looking at the picture below (and lacking the proper part) - I think that I would engineer a threaded rod or long screw - tapped through the side of the dizzy to stop the pivoting point plate where I wanted it to stop - and locked with a nut. 
The advance scheme that I have been running (and I believe Mark too) is for engines that are pretty much stock (low to moderate compression / factory style cam characteristics): 10°-12° Initial 13° in the Dizzy (26° at the crank) for a total of 36°-38° degrees of combined advance (vacuum pot installed but not connected). Spring set in the centrifugal replaced with lighter action - to get full mechanical at 2500 -3000 rev's (2800 target). We've then got the vacuum advance pot limited to an additional 8° (crank). Both Mark and I are running live vacuum advance at idle, so after using the initial to start - they are idling at 18°-20°. It keeps them cool and runs up the manifold vacuum. I use a dampening orfice in my vacuum line from the carb to the dizzy. Be aware that on some enignes (high compression most likely) - it doesn't work. The dampener is simply an orfice that prevents the vacuum pot from slamming around too quickly. For mine, I inserted an electrical "butt splice" and crimped until it worked to suit me.
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By oldcarmark - 15 Years Ago
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Before you get too worried about adjusting the vacuum advance,install the dizzy and see where the advance is set for now.As much as its very annoying you can still replace the one on there now with one that is Allen key adjustable.Shouldnt have to being new but that may be the answer if its too much vacuum advance as set now. Steve-what size is the Allen key for these adjustable ones?
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By Talkwrench - 15 Years Ago
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Guess I'll come up with something like you said Steve, So you are running manifold vacuum not ported? If anyone knows where I can get a cheap one let me know.. This is annoying.. I just had a Vac advance unit come out with that dissy but it was for my Cuda. Thats adjustable...
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By GREENBIRD56 - 15 Years Ago
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This photo shows the "STANDARD' part I came up with for my Duraspark II conversion dizzy - but you would want a different part number I'm sure for the points style of pivot plate. Somehow I keep thinking the one you want is the STANDARD VC-221 - but don't take that as accurate without checking it out. 
How late did they use points on the "down under" Ford big sixes and v8's? The vacuum pot is virtually unchanged in mounting and function over a huge span of years here. You might take the dizzy to a parts house and have a look at what they've got right there in Perth. Your outfits don't run backwards do they?  Choice of the "live" and "ported" vacuum turns out to be a sort of religous experience. I think it just turns out to be which method results in the best tuning for the individual (man or motor). I like the "live" because the engine idles cooler and (my opinion here) starts quicker with lower initial advance. Gives a nice idle vacuum reading too. Searched around a bit and it looks like the STANDARD VC-198 is the point distributor version. Its for a '69 302 I believe.
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By shakey pete - 15 Years Ago
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I thought that throttle responce controlled the amount of vaccum at the dist. weather it,s taken from the intake or carb. if you are looking for better response get a dist from a 57 ford and get it set up on a dist machine to get the advance curve set for your application then you have the best of both worlds just my thought shakey Pete
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By stuey - 15 Years Ago
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Talkwrench good morning i've a Crane version and it uses a 3/16" allen key stuey
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By Talkwrench - 15 Years Ago
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I had no idea crane did them ? ... Shakey it is a late model recoed dissy thats why I thought I would come standard with adjustable vac advance, and I have springs on the way to do the curve. Now I am going to have to work out how to disassemble soon.. Tips guys?
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By GREENBIRD56 - 15 Years Ago
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I think the "STANDARD" brand of vacuum pots use a 3/32" hex which is a bit smaller than 2.5 mm - in case maybe you just haven't tried a small enough instrument. This picture isn't the one I want but its better than none.....its a Motorcraft type distributor, which I hope you've got. 
You remove the vacuum pot attachment to the swiveling point plate (small "C" clip) and two screws and it comes off easy enough. The point plate only has a pair of screws that mount it down into the dizzy body - off over the point cam, and you end up with a view much like this one. The upper rotor shaft is retained by a clip hidden down in the bore under the point where the rotor fits. Cleaned up - you'll see a pair of "whisker" sized legs coming up the bore - they spread to release the clip on the shaft. When the clip is gone - and the two flyweight springs are removed - the upper rotor shaft will come up out of the dizzy. This would only be necessary if you want to change the advance "curve".
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By stuey - 15 Years Ago
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 hi there gawsh i feel silly it was 3/32" not 3/16" as i said previously i don't think Crane do these anymore i can't find them on their website. (note to self engage whats left of brain first) stuey
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By Talkwrench - 14 Years Ago
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Today I have finally opened up the dissy to do the mods.. Looks like I am outta luck here too! There is no adjustment for changing the timing internally, no slots marked 13 or whatever.. nothing, just has two slots the same. . Guess I will fit the 925D springs and see how it goes with the Pertonix kit fitted. I take it that those slots should top out at 36* ?? God knows what the vacuum advance is gonna do......
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By GREENBIRD56 - 14 Years Ago
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No worries, Mate....Don't give up the ship!....This is how the "old school" Autolite dizzy gets its advance stops changed.......braze or silver solder in the ends of the slots to shorten the travel.... 
Then opened to a predetermined length with a 1/4" diameter rat tail file...... 
If you want a different number of degrees of travel - send me a PM - and I'll figure it out on the CAD drawing i have in my computers. (The one in the photo has had its cam cut off to fit a Duraspark reluctor)
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By Talkwrench - 14 Years Ago
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Thanks Steve, I put the 925 advance springs in and left it as it was. Got her running ok and set it up with 7.5* at idle no vac, this gave me 40* mech advance, hooking up the vac put it at around 50* It took her for a spin and all was well, so uped it to 10* I think that gave me somewhere around 45* mech advance and with vac say 55* Now this seems alot but it runs well and doesn't ping at all... The Petronix was a lot more acurate under the timing light, hence its very smooth, can't say there has been revelation since fitting it but it's probably decieving as it is so much smoother.. 
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By 62galxe - 14 Years Ago
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Steve just curious why you picked the vc223 for duraspark use. Thanks,Kenny
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