Is there anybody out there who has a set of instuctions for the old (Two piece cap) Mallory Distributor like was used in 8BA style Fords "back then"? Models ZA, ZB, ZC etc. Trying to set up the advance curve on a machine but nothing seems to be working. Any help will be appreciated.
There was some one asking the same question the other day over on the Ford Barn site.You might try a search over there, as the answer was a strange one I could not figure out.You may need a vacuum type delay unit that they had to use in order to work. I know I had to use some strange unit on mine way back when & I even still have the unit.If I can be of help, let me know.
That was me on the Fordbarn. I've a friend with a distributor machine and considerable ignition experience but he can't figure out how to regulate the advance to achieve my specs: 4 deg initial, 22 deg total, all in by 2000 R.P.M. It appears to have a vacuum brake which is spring loaded (high vacuum pulls it off, low vacuum allows the spring to apply) very similar to the old stock Ford cam mounted distributors.
Talk with Mike Mancinni (vintage ignition) on here he set mine up. He does restoration, parts and set up of these old distributors. The first thing he will suggest is a conversion to mechanical advance, the vacuum system is seriosly flawed for performance applications.
I almost sure they were all alike mechanically so it should work. I'd love to have a copy. (Actually I've been trying to psych out their model numbers for some time. I think Z=Y)
You can call Mallory tech line at Mr.Gasket company. They have alot of tech releases still available. Maybe they have the documents that you are looking for. http://www.malloryperformance.com/
Mallory part numbers and model numbers vary endlessly... If keeping the brake system, basic setup of the centrifugal curve should be done with brake on, as that is the full throttle curve, then the brake releasing under cruise conditions allows a bit more advance, probably not as much as needed but better than a pure centrifugal system. I think there are instructions for one of Mallory's spring and recurve kits posted on the Century performance Mallory site. It may not be the exact generation you have, something that is very hard to figure out anyway with Mallory's multiple generations and endless changes to numbers, but I think they will be generally applicable...I think one of the Mallory springs allows the sudden quick advance right off idle and then a stiffer set can take over. The better stock distributors start cranking in advance at like 500 and are all ijn very quickly, like 1200 or so, so most likely you just need to start with the lightest everything. For starters, try to use specs from an 11A-21A distributor. Your total mech advance should be stamped in there on the part that restricts the limiter slot, or it can be measured on the rim of the distrib. There's an extra plate in there somewhere that drags on the brake, and moves in the extra advance when car is at low throttle... I think I have the instruction sheet for your distrib!
Bruce: That's the kind of info we need! I've copied your message but I'd still like a copy of the old instruction sheet. If you will, send it to my e-mail address: [email protected]. Thanks, Dale the brake releasing under cruise conditions allows a bit more advance, probably not as much as needed but better than a pure centrifugal system. I think there are instructions for one of Mallory's spring and recurve kits posted on the Century performance Mallory site. It may not be the exact generation you have, something that is very hard to figure out anyway with Mallory's multiple generations and endless changes to numbers, but I think they will be generally applicable...I think one of the Mallory springs allows the sudden quick advance right off idle and then a stiffer set can take over. The better stock distributors start cranking in advance at like 500 and are all ijn very quickly, like 1200 or so, so most likely you just need to start with the lightest everything. For starters, try to use specs from an 11A-21A distributor. Your total mech advance should be stamped in there on the part that restricts the limiter slot, or it can be measured on the rim of the distrib. There's an extra plate in there somewhere that drags on the brake, and moves in the extra advance when car is at low throttle... I think I have the instruction sheet for your distrib![/quote]
Cain't...ain't got no TECHNOLOGY! But PM me your snailmail address and I'll start digging in the information bunkers. Do some looking for advance info from Ol'Ron on Fordbarn--he is currently studying this actively. You won't be able to meet his vac advance schedule with Mallory tech, but steal his current advance ideas for your centrifugal curve. Crab distributor using 11A advance is even more agressive, also is Mallory pattern with a brake, but adjustable.
21A uses 4 degrees static, 26 total, in one partial spec I have here...more detail in bulletins, advance starts right off idle and finishes down low, like 1200 or so. I think this is the full curve, and can be dragged down by tightening brake if so needed. Ron I think suggests somewhat less centrifugal but can add in more at part throttle because he uses a Chevy distributor with curve lowered for flathead.
The Jalopy Journal
