Thanks for all your help, now if the snow would go away so I can go out and play.

John F

Ballwin, MO

As Frank was saying about limiting the slots......the older distributor slots have about 20° of travel which fights you when trying to build a performance advance curve. Ford used these with stiff flyweight springs and 3°-6° initial to net 35° to 40° total at some unreasonable (high) RPM. Below is the mod to the rotor slots of the older distributor that limits the mechanical advance to 13° at the distributor (thus 26° at the crank).

 

So, if you give it an initial of 10°-12° the total will end up around 36°-38° - just right for a performance mechanical advance curve. The other type of upper rotor will have two mechanical advance limit slots stamped with a number - like "13L" or "18L" - there are several more around. These are distributor degrees - double at the crank when fully opened. The factory 13L would be a nice find - but you can open up a "10L" with a file if you need to or braze up a longer (hot rodders adapt).

When you run a vacuum advance pot - on top of the performance mechanical advance - you can get "over-advanced" at cruise conditions. One of the '85 Mustang adjustable advance pots would be a good item to locate - or Crane offers an adjustable Duraspark pot (#99607) that comes with a set of advance weight springs to quicken the curve. The idea is to run all of the mechanical you can - then add just enough vacuum advance to let her cruise without a knock. 

 
 Steve Metzger       Tucson, Arizona

John F, Steve,

          I believe you can still buy a rebuilt distributor from NAPA or AutoZone  for an early '60's 292 which will have the correct shaft. You might want to limit the mechanical advance in it (Solder or braze a slot up) and run more initial timing, but the duraspark parts should fit that case. 

TED, can this and Steve's answers & photos be made sticky or put in a tech file? This should be the basis for future answers to the question. Well done.  

Frank/Rebop

Bristol, In ( by Elkhart) 

John - It depends on which post '57 Y distributor you have - early or late. This picture shows the upper rotor shafts of the two types. At upper left is the early arrangement with a fixed point cam and the two rectangular slots for the advance mechanism. At lower right is the later type upper rotor shaft used in the housings with the "three lobed" shaft cover (like the '79 donor distributor you've got in hand). If the housings are a match, just start swapping parts.

If you have the older distributor it can still be used - by modifying the upper rotor shaft to remove the point cam and turn down the upper tube to fit the reluctor. The one below has been altered to accept the reluctor and carry it at the proper height. The fixed cam is hardened, so you'll need to grind it down a bit to save machining time and also save some cutting tools.

If it turns out that this operation is what you need - send me a PM with an email address and I'll send you a PDF file print to take to the machine shop. The link below will get you to the drawing I made of the wiring schematic. This one is made to utilze the Duraspark II controller with the "blue grommet" 

http://pages.sbcglobal.net/mshum/HoLun/WIRINGSCHEMATICT-BIRD1.jpg

 

 
 Steve Metzger       Tucson, Arizona

I have a distributor from a 79 Bronco 351 M. I also have the wiring and the module. Will the shaft fit the Y-Block distributor Housing?

John F

Ballwin, MO

Greetings John - up in the RH corner of the Y-BlocksForever window is the word "Search". Click it up and type in the word Duraspark . You'll probably get more information than you wanted.

You will need a seventies Duraspark II distributor to use as a donor to get the necessary stator plate parts for the conversion. They will fit on the body of your '59.

Holun has the wiring diagram stored away on an accessible site - I'll hunt up the address and try to get it on this thread for you.

 
 Steve Metzger       Tucson, Arizona

I want to convert my 59 Ford 292 to a duraspark. Has anyone done this and what's involved?

John F

Ballwin, MO