Carrier V-8 distributor question

[Lynn Eades]

Richard, I might have it wrong.
Looks like we are all on the same line of thought though.

[colin jones]

Here's a couple of photo's of a spacer plate I made about 2 years ago when I changed a bell dizzy for a crab one and a photo of the button adapter.
Colin.

[Darrin Wright]

Continuing on with the same line of thought....

I have the earlier helmet distributor on my V8, all original to 1941, when I did the rebuild I considered changing over to the crab distributor, in order to do this I had to look at acquiring the adaptor plate (as Colin has pictured) and the button.

This indicates that the front timing cover was also different.

So it will be a combination of distributor, cam shaft gear and timing cover fitted to the engine.

I would also consider, depending on level of work done to the distributor, going back over the distributor to ensure that it is back together again. easy way to possibly tell is the rotor should line up with the 2 sets of contacts for the plug leads, as it rotates. Then there is the timing or phasing of the points....

[Lynn Eades]

Darrin, The crab dizzy (21A) vacuum brake is operated via drilling back into the timing cover. The older (divers helmet- 68) dizzy has a pipe going directly off the dist housing. It would require a later timing cover as well.
The vacuum brake is important. It stabilizes the spark timing and alters timing to suit throttle position.
The early dizzy has the reputation of being the better one apart from a few downside issues, like being harder to get in and out. They are said to be more water proof (does it make a difference?) You would need the correct conduits as well because the crab has two ht leads that cross over to the opposite side (unlike the divers helmet that sends 4 leads down each side to the 4 plugs on that side)