Distributor Rotor & Cap Rapid Erosion

[type26owner]

Turns out the MG guys have beem hoarding the best quality brass 23D caps all along for themselves. <_< Got the ones I ordered from the B-Hive and sure enough they are for real. Don't know the manufacturer's name yet but stamped inside the cap it says "Made in USA". Reasonably priced too at $15.

Their bumblebee wire is kinda like but not a perfect match to the original. Anyone remember that stuff besides me? On the original Lucas wire did the black strip spiral around the lenght once every couple of inches? On this stuff the black stripe does not spiral at all and is wider then I recall it being.
-Keith

[BillGavin]

The bumblebee wire I'm familiar with does not have spiral stripes: the black stripe is straight and fairly wide, about to scale with the tracer on low tension wiring. I got mine from Dave Bean, and it matches some old wires I have from long ago.

There may have been other varieties available.

[steveww]

You can get the bee wire from www.holden.co.uk as well. Will be getting some when I put the engine back together.

[type26owner]

I didn't recall it spiraling either but I was assured it did by a couple of sources. Close enough for me! Lets see if I can burn up these brass caps now!!!
-Keith

[type26owner]

Hey Bill,
Now that I've squirreled away a lifetime supply of these I'll confirm that Don Tingle can indeed still supply the original Lucas dizzy caps. He tells me they are getting rather scarce and the current price reflects this.
Thanks!
-Keith

[type26owner]

Ground a hole through the side of a 23D dizzy cap to look for the angular phasing of the rotor to the cap's contact post when the Pertronix reluctor triggers the hall effect switch. What I saw has raised more questions then it answered. The leading edge of the rotor's conductor appeared to be centered with respect to the cap's post. This could be impacted by any time delay of my timing light but I have no idea if that's significant or not. Clearly that's why the leading edge of the conductor on the rotor is pointed to increase the density of the electric field lines. The trailing edge has a radius of about 2mm so it can chop off any remaining charge crossing the gap as a plasma. Have to wonder how long in angular terms the spark line exists though. Can imagine why installing a high voltage coil which slowly collapses it's field would be a silly thing to install on a twincam if it's not really necessary.

I should do this measurement as if setting the static timing. That way I can stick a small dental type mirror into the hole and see the exact angular alignment when the spark plug gets fired. The main concern on my part is the contact post in the cap appears to be burned mostly only on the leading edge by the high voltage spike. The question is the arc going through the plasma suppose to sweep along the entire surface of that cap's contact because the pointy end of rotor makes it behave like that? Where is the ideal spot for the HV spike to take place so the erosion is minimized? Suppose it would be good to measure the dwell also.