TFI distributor in older SBF?

[bronco italiano]

So I have a 1970's 302 block with flat tappet cam that I converted to explorer EFI.
-Had a new Mallory 7970404 TFI distributor with steel gear (has to be changed to melonized or composite) that I installed.
-Was there any block differences regarding the EFI distributor fitment of rollerblock vs. the flat tappet blocks?

 

[jamesroney]

So I have a 1970's 302 block with flat tappet cam that I converted to explorer EFI.
-Had a new Mallory 7970404 TFI distributor with steel gear (has to be changed to melonized or composite) that I installed.
-Was there any block differences regarding the EFI distributor fitment of rollerblock vs. the flat tappet blocks?

Check the shaft diameter of the distributor at the gear. ALL of the factory steel gears are .530 nominal, and all of the factory cast gears are .467 nominal. *** @lars I am wrong! Thanks @Broncobowsher *** There is a large bore .530 cast gear on the 85-94 5.0 non-HO truck and car. PN E5AE-12390-BA

But I have yet to find a small bore Steel gear except in aftermarket. So this would prevent you from making the “mistake” of putting a steel gear on your cast cam. (but not the other way around)

Aftermarket also makes both gears in both sizes. (So 4 total). Just pick the one you need.

You don’t need a Mellonized or composite or bronze gear unless your flat tappet cam has a special gear.

You DO need to make sure that the oil pump drive has enough hex shaft to accept the extended length of the distributor hex. All factory shafts work fine, but some aftermarket have a shoulder. 99.9% that yours is ok.

And yes, all of the blocks are functionally identical.

 

[lars]

Check the shaft diameter of the distributor at the gear. ALL of the factory steel gears are .530 nominal, and all of the factory cast gears are .467 nominal. This is to prevent you from making the “mistake” of putting a cast gear on your steel cam.

Aftermarket makes both gears in both sizes. (So 4 total). Just pick the one you need.

You don’t need a Mellonized or composite or bronze gear unless your flat tappet cam has a special gear.

You DO need to make sure that the oil pump drive has enough hex shaft to accept the extended length of the distributor hex. All factory shafts work fine, but some aftermarket have a shoulder. 99.9% that yours is ok.

And yes, all of the blocks are functionally identical.

Just learned something. Thanks James!

 

[jamesroney]

Just learned something. Thanks James!

Since I did this last week, and since we are sharing...It is worth noting that the steel gear from Edelbrock is about $30. The same gear from another famous Cam maker is about $120. A small shaft cast gear is about $10.00 from Dorman.

You never know which shaft "standard" the aftermarket distributor maker is going to use. I can guarantee you that the MSD ready to run Billet distributor is small shaft. (.467)

This stuff rarely comes up, because no one in their right mind would want EFI and a flat tappet cam, because if you go sequential EFI, you want to change the firing order, and you want a bigger LSA for the ECU.

But the OP seems to want to dig a giant hole, and I am happy to provide him with a better shovel...

 

[bronco italiano]

I had the ECM reworked many years back for the Comp cam and older firing order to prevent the shovel issue I would have gotten into.
Thank you

 

[Broncobowsher]

The 80's truck distributors were TFI for a flat tappet from the factory. Nothing specialy.
Regular off the shelf part.

I don't remember if the trigger wheel is different on the truck vs. car. I know the car is sequential and has an odd tooth to call out #1 TDC firing. The truck may or may not have that odd tooth. Batch fire shouldn't care, but maybe they did? I've never had an original truck distributor in my had and cared enough to look if the trigger wheel has the one odd tooth for #1 or not.

 

[jamesroney]

The 80's truck distributors were TFI for a flat tappet from the factory. Nothing specialy.
Regular off the shelf part.

I don't remember if the trigger wheel is different on the truck vs. car. I know the car is sequential and has an odd tooth to call out #1 TDC firing. The truck may or may not have that odd tooth. Batch fire shouldn't care, but maybe they did? I've never had an original truck distributor in my had and cared enough to look if the trigger wheel has the one odd tooth for #1 or not.

This is good to know and makes sense. I will do some investigation. If there is a flat tappet TFI distributor, I need to know if it is big shaft, or small.

Does anyone have an MPC to show the distributor drive gear part number for the mid 80's truck? Calling @Oldtimer

 

[Oldtimer]

I have no MPC that covers trucks.
Ford seems to think a Bronco is a car?

 

[tasker]

The drive gears were always serviced with the distributors back in mid 80's from Ford.....I may have a list someplace, will look

 

[bronco italiano]

I pulled the distributor
Gear is on the .531" section and just below the gear the shaft goes .430" for oil pump shaft.
I just bought a Rockauto cardone for a 1985 F150 with the cast gear.

 

[tasker]