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By Bruce Compton - 12 Years Ago
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I've got two modified '57-'59 distributors (to fit my 256" Merc). Both have only around 15 crankshaft degrees max. I thought they should have 12-14 dist. degrees advance which translates to 25-28 crankshaft degrees at around 2200 RPM. Both have three degrees advance at idle (500 RPM). If I set the static timing to 10 deg., when I start it it goes to 13 deg. I tried adding tension to the low speed (light) spring, but it did not change much , maybe one degree. The car runs strong with 14 degrees initial, but I'm concerned with doing damage. What gives?? Any advice will be appreciated. Thanks : Bruce
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By Bruce Compton - 12 Years Ago
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They are the dual advance type. One is an FEK and the other is a B9AF. I'm beyond the loadamatic and teapot. Thanks : Bruce
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By GREENBIRD56 - 12 Years Ago
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I'm thinking you have an upper rotor with slots like these?
Do you have the flyweight pins limited to a specific amount of travel?
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By Bruce Compton - 12 Years Ago
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There are no numbers on the plate, and no choices like the later Ford distributors. Bruce
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By GREENBIRD56 - 12 Years Ago
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The distributors with the slots shown above will reach 20º of distributor advance with the flyweights fully extended - but that is 40º at the crank. They were used with stiff springs and engines statically timed down near TDC to stay away from over-advancing.
When recurving a distributor like this one, it is customary to shorten the slot to limit the total travel. That way the chosen initial advance and distributor contribution wouldn't sum to more than required. At 14º initial you would want to limit slot travel to a little over half what is shown to net 35º-36º.
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By Oldmics - 12 Years Ago
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Greenbird
Would you tell me the numbers/letters on the distributor that is shown in your picture?
I only know of one factory dizzy that uses that 10* marking.
Oldmics
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By GREENBIRD56 - 12 Years Ago
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Truthfully, I don't know where the photographed outfit went (with "10" marked on the upper rotor). The one I have retained and modified is on the Greenbird's 312 and out of a VAPEX re-manufactured assembly - and no stamped marks were on it. Original slot length of that one was .510 (20º) - and the one in the photo looks shorter. For a reference, the pins are .250 diameter and reducing the total slot length to .460 nets 13º distributor advance. The remaining slot in the photo is less than .210 (comparing it with the pin), so it could be a factory part with only 10º travel.
That wouldn't be too common an item, the rotors I remember seeing all had the long slots. Will have to look at the stuff in my garage attic........I believe there is an Autolite style distributor up there.
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By Talkwrench - 12 Years Ago
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Mine has 12 degrees initial with a total of about 34 mechanical and all in by a very early 2250 rpm. I have the Mr Gasket D245 [D245?? I think help Steve / Mark] advance springs . I do have vacuum advance as well, with vacuum i think I have a little over 50 degrees.
Note: I do run quite a rich.. I have seen 1 or 2 detionation spots on a random plug but nothing I would panic about, no pinging to be heard.
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By Bruce Compton - 12 Years Ago
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O.K. guys, here is what I found. The first thing I did was remove and mark my crankshaft pully (solid cast iron with no rubber) and mark it off in 10 deg, incriments to a total of 40 degrees. When I reinstalled it and checked the timing with the vacuum off, it was idling at around 25 degrees (at 500 RPM). Enough messin' around, I removed the dist., and found that the advance was sticking at a partly advanced state. I robbed another dist of it's light spring and put it in place of my heavy one and added a little more tension with the bendable arm. I now have 40 degrees of distributor advance at 3000 RPM plus whatever I set the initial at, so if I set it at 10 deg., my total without any vacuum will be 50. This sounds like way too much. I had a close look at some advance plates (the ones with the two slots) and discovered that the ones with no numbers have slots that are 0.509" and the ones marked 13 deg. have slots that are 0.450" long. The numbers are confusing me as all '57-'59 Ford distributors ars supposed to have around 22-24 degrees maximum mechanical advance, yet mine has around 40. Im thinking of installing the 13 deg. plate. Thanks : Bruce
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By pegleg - 12 Years Ago
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Install the 13 degree plate and set your initial at 10 degs. You double the dist no. to arrive at crank degrees. That will give you 13+13+10. or 36 degrees.
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By oldcarmark - 12 Years Ago
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Don't forget to ad the vacuum advance #.Vacuum advance comes in initially and than again at cruising speed when vacuum is high again.You should be aiiming for 42-44 total available advance.
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By Bruce Compton - 12 Years Ago
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Thanks guys. I installed the 13 deg. plate with two light springs and all is well. I now have 12 initial plus 26 centrifugal all in around 2200 RPM. Cheers : Bruce
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