I have a 85/86 block in my 1973 F250. I didn't perform this swap and I have very limited knowledge of the history of the engine or internal components. I am having trouble with my distributor and need to replace it. The distributor is not an 85 +newer model, based on the lack of the 6-pin module. Up to 1984 the distributors used a 3-pin plug. That's what I have.

Here is the issue.
1) My existing distributor appears to have a steel gear. The gear has very clear machining lines and has no indicators of being cast iron.
2) I am fairly sure I have a flat tappet cam. The push rod length is approx. 6.875". I don't have a precision way to measure the rod - that measurement is from a cheap tape measure.

Here are my questions:
1) Is there any other way, aside from taking the intake off or pulling the cam, that I can be sure I have a flat tappet cam?
2) If I do have a flat tappet cam, is the cam gear toast because of running with the steel distributor gear? Is there something I can look for to tell if the cam gear is ruined? I can see the cam gear from the distributor hole and turn the engine to examine it.
3) What happens if you use a cast dist. gear on a roller cam? Will the dist. gear get chewed or the cam gear? I'd rather error on the side of ruining a dist gear if I pick the wrong material than ruining the cam.

Steel distributor gear-2 by FuriousF250 posted Apr 9, 2024 at 7:46 AM

Steel distributor gear-1 by FuriousF250 posted Apr 9, 2024 at 7:46 AM

 

not 100% sure about a truck SB, but my 85 mustang gt was the first year of the roller camshaft , so it's possible you MAY also have one, if so the dizzy gear must be compatible ,