Does anyone know what the application is for this distributor? How much advance? Also, based on previous topic it seems Y blocks with hot cam need a minimum of 14 degrees initial advance. I am going to have this distributor modified based on 14 to 18 degrees initial advance. Any suggestions on how soon to bring it in. The car is a 57 custom. 3 speed O/D 272, G heads, 57 autolite and 57 intake. Cam has 238 @ .50, .485 lift on int. and ex. and 16 degrees of overlap. The car was purchased from the late owner's family and we have limited knowledge of the cam. We are replacing the 600 Holley with the Autolite carb. and this distributor will be installed. Thank you all very much!!

Re; application, I got this from John Gutheil, sales manager for PerTronix, a couple of weeks ago,

"The FEH-12127-A and A2 (typically the "2" represents an engineering change), along with the FEK-12127 are all identical, save for some minor external casting changes. The A2 is the most common. There is also an FEJ-12127 which is 1957 Thunderbird Only as it is a Tach Drive distributor."


South Australia

Here is a graphic from Ford literature that shows the ranges of available adjustment with factory parts - very hard to predict what's on the inside from the numbers on the body casting.



These are not indicative of performance type curves - they show the range of what arrived on vehicles under warranty, to be driven by the average owner. Many variants exist and they probably can be researched by the individual manuals for the various vehicles, displacements and rated HP levels.

To set one up "your way"...........

This is done with the vacuum advance tube temporarily disconnected and the carb port for it plugged. I usually shoot for an initial "all in" 36º total mechanical at 3000 engine rpm (1500 distributor). That depends on establishing the "initial" low end number (say 14º) by tuning the idle and starting characteristics and subtracting from the 36º to establish the mechanical stops inside the distributor. You then choose a set of springs that results in the "all in" rpm level desired - and that either gets done on a "SUN" distributor machine (or similar) or in the vehicle by perseverance.

Depending on several factors - actual engine compression - fuel quality, etc - the engine may tolerate and respond to a quicker rate (say all in by 2800 or 2500 rpm). This tolerance can be based on engine temperature - variable fuel supply octane (on a road trip) and it might not be best to push things to the limit.

Which is the reason Ford used the conservative curves shown above...................

 
 Steve Metzger       Tucson, Arizona

Steve,

Thank you very much! the distributor guy thinks that the 312 distributor may max at 26 degrees. If correct and the motor likes 14 initial then we end up at 40 total. Only one way to find out. Based on previous discussions the vacuum gauge seems like a great way to determine initial advance; then old fashion test drive to determine max advance (high gear flat road and find out were it pings). Then we can modify the spare distributor to the desired initial and max advance.

If I am missing something let me know. The motor is most likely less than 8 to 1 compression and perhaps 40 to 42 degrees will work. Very interested to know how much advance guys have used in their y blocks. Thank you again!

Be sure to take into account the vacuum pot - it will add advance every chance it gets, depending on manifold vacuum. So for instance, if there is more than zero vacuum as the engine accelerates - you will have a bit more than is indicated by the mechanical settings alone.

 
 Steve Metzger       Tucson, Arizona