I have a '79 F-150 with the 400M. It has the electronic ignition. The engine starts right up and the timing is set at 4* advanced. The problem is there is no "mechanical" advance as the engine rpm is increased. I'm assuming the ignition module is the issue.
Has anyone removed the Ford setup for the aftermarket HEI Ford ignition simillar to the GM HEI? Or anyone have an alternative setup to suggest?

 

timing should be around 10-12* btdt

 

Your distributor is the problem, not the ignition module. Mechanical advance is built into the dizzy.

 

The timing is set at 4* BTDC per the stick on the hood.

The only thing inside if this distributer is the pickup senser. There is no typical weight advance mechanism in this unit!

 

Go pop the distributor cap off and twist your rotor counter-clockwise. Assuming its not completely jammed up, it'll turn at good bit, thats your mechanical advance. Ive been having problems with mine.

 

how far are you revving up the engine? My mechanical advance doesn't start rising until about 1500 or so, it's also the stock curve and nothing with more performance in mind.

 

You can't see the mechanical advance just by removing the distributor cap. All you'll see is the pickup module. You have to remove the breaker plate and base plate to see the mechanical advance. You can't do that until you remove the armature. There's a fair amount of work involved to get deep enough to be able to see the mechanical advance.

Mechanical advance is controlled by centrifugal weights at the very bottom of the distributor. It's not controlled by the ignition module. How are you determining that your mechanical advance is not kicking in?

 

Let me describe this distributor because some must have something completely different from mine.

The cap is ~5'' OD and is grey.
The body is ~5" OD by 2 1/2" tall and is blue plastic.
This all is on the Alum base which goes into the block.
Inside the distributor is the trigger device and the vacuum advance hook up and of cource the rotor. NOTHING ELSE!
Trying to turn the rotor counter clock wise or clock wise produces no movement

 

Maybe your mechanical advance is locked up then. Idk if the weights are under a plate or something, but they are in there. Its physically impossible for the ICM to retard or advance the ignition timing. The ICM controls dwell time.

EDIT: Yeah, what fmc said.

 

Sounds like an aftermarket dizzy, but the same physics still apply, there's a mechanical/centrifugal advance mechanism inside that will advance the timing as your rpm's increase.

 

I removed and disassembled the distributor. It is a Motorcraft (Ford) unit. The mech advance is under the trigger mounting plate and it is not in good condition.
So a Ford HEI distributor has been ordered which will help clean up the engine compartment and simplify things. The wireing for this original ignition was in need of repair.

Thanks for the help everyone!!!!!!!!!!!!

 

Don't throw it away. You might wind up needing it back.