Can I use a Duraspark?

[blueroo]

Yes, I know, I have a 1964 170 and the Duraspark shaft is bigger than the 170 dizzy shaft. But can the dizzy hole be enlarged with a hardened drill bit/dremel/whatever to accept the Duraspark.

My 43 year old dizzy is worn out. It has an Ignitor, new cap, new rotors, but the main shaft has a lot of slop in it. I hear all this good stuff about the Durasparks and figure I have nothing to lose.

Can it be done, and can it be done in car by dropping the oil pan so the shavings fall out? Or would I be better off getting another 170 dizzy?

Also, I have the Autolite 1100 with the SCV of course so would I need to do anything for the vac system by changing to Duraspark?

 

[rbohm]

8) two ways to go on this;

1: ream the pilot hole out to fit the dist shaft

2: turn the dist shaft down to fit the hole

either way you need to swap the oil pump and oil pump drive shaft for the larger 5/16" shaft.

 

[wallaka]

My 2 cents: cut down the dizzy shaft vs. reaming out the hole. It's much easier to fix if you mess it up (just buy another dizzy).

I've seen it done with sandpaper. Just go slow and check for fitment often.

 

[addo]

Exactly. It's not hard chromed or anything; just good tool steel. A general engineering shop should be able to do it very easily/cheaply.

You only have to turn down from about 10 thou inside the gear (eliminates any "shoulder" binding).

Remember that you probably also need the large oil pump drive shaft, and the 200's oil pump.

AzCoupe has some Bosch electronic dizzies which fit without turning down the pilot. While these provide a better signal than a regular Duraspark (and don't really need an MSD box either) they are harder to recurve.