How to tell what distributor gear on old Distributor: EFI Swap

[monk302]

Hey everyone,

I am currently in the process of doing my EFI swap. I have an engine in the car that was rebuilt by the previous owner. I know that it has the older firing order, not the newer HO firing order. So right now I am trying to figure out what kind of gear I have on my distributor. How can I tell? I have a newer distributor from the donor that I am ready to put in. I am assuming that I cannot put the newer model distributor in right?

Thanks,

Mike

 

[Tubo(2-bo)]

The origional non EFI engine probably had a cam not compatible with the EFI dizzy. IIRC Mallory makes a dizzy gear compatible with both.

 

[damannhw]

The older gear is most likely a cast iron gear. The newer cams require the steel gear. Since you have both dizzies, you can compare them. The cast iron gear will have a textured surface on it's main body (not the gear area) like a head or engine block. The steel gears have a smooth finish that looks machined. Just had to do this myself last week.

If your current engine does have the cast gear, just be sure to reuse it on the newer dizzy. You may have to re-drill after pressing it on (It will need to be pressed). The holes will probably not line up. Make sure you take good measurements and place it the same distance when re-installed. Press it back on and drill your new hole 90 degrees away from the previous hole.

 

[monk302]

The older gear is most likely a cast iron gear. The newer cams require the steel gear. Since you have both dizzies, you can compare them. The cast iron gear will have a textured surface on it's main body (not the gear area) like a head or engine block. The steel gears have a smooth finish that looks machined. Just had to do this myself last week.

If your current engine does have the cast gear, just be sure to reuse it on the newer dizzy. You may have to re-drill after pressing it on (It will need to be pressed). The holes will probably not line up. Make sure you take good measurements and place it the same distance when re-installed. Press it back on and drill your new hole 90 degrees away from the previous hole.

How do you actually get the gear off? I have taken the pins out but cannot for the life of me get the gear off. Any special techniques?

 

[Dark Knight]

FWIW, ford made 2 shaft diameters for the dizzy... make sure you get the right gear..

 

[damannhw]

How do you actually get the gear off? I have taken the pins out but cannot for the life of me get the gear off. Any special techniques?

You will have to "press it off" with a press. If you have access to one, you will need to have a "backer" to support the gear while you press the dizzy shaft out. I usually use a couple of old pieces of 1/4" thick steel behind the gear on each side. That way the dizzy shaft can push down and out of the gear. You can probably find a local shop to do it for you too pretty cheap or maybe free.

 

[monk302]

The origional non EFI engine probably had a cam not compatible with the EFI dizzy. IIRC Mallory makes a dizzy gear compatible with both.

Does anyone have a part # for this one? Thanks.

Mike

 

[monk302]

Bringing this one back, could I use a bronze gear? I called Mustangs Plus and they said to use their bronze distributor gear to mate a EFI distributor to an older non EFI engine.

 

[D.Hearne]

When you press the gear back on, align the hole in the gear, 90 degrees to the hole in the shaft. Otherwise the gear may not be in the correct position in relation to the cam. Once the gear is in it's proper place, you have to drill a new hole thru the shaft for the pin. Ford Racing's steel gears come with the instructions for this operation and includes the correct placement dimensions for the gear.

 

[monk302]

Would a brass gear work in both situations? Whether the cam is iron or steel?

 

[thehueypilot]

Would a brass gear work in both situations? Whether the cam is iron or steel?

It will work until the steel cam chews the teeth off of the brass gear and the shavings circulate throughout your engine.....that is until the teeth finally give way and your oil pump stops turning....... and you know what happens after that........

 

[bnickel]

It will work until the steel cam chews the teeth off of the brass gear and the shavings circulate throughout your engine.....that is until the teeth finally give way and your oil pump stops turning....... and you know what happens after that........

he doesn't have a roller cam. he is trying to get the right gear for the EFI dizzy to work his old flat tappet cam.

monk, i don't know if you realize this or even what EFI setup you're using but the HO EFI uses a different firing order for not only the cam but also the injectors. if you have an HO EFI from a mustang/mark 7 LSC you will need to change the injector firing order to match your 289/302 (?) cam. the Lincoln town car, crown vic and ford trucks use the same firing order as your current 289/302 (?)