123 Distributor / Setting timing Options

[rjames]

For those that have a 123 Distributor, I need some help setting my timing. I'm probably over thinking all of this but I've read several different threads on setting the timing with this distributor and I have interpreted them all differently.

I'm running a stock 2.0 w/ DJet.
The 123 distributor setting I'm using is 'B' (negative advance), and has a max advance of 22 @ 2700 RPM.

With my new-school timing light that allows me to set the advance, (with vacuum line from the tb plugged) do I:

- Set timing light to 27 advance and rev to 3500 RPM and time to the TDC mark?
- Set timing light to 0 advance and rev to 3500 RPM and time to 27 degree mark (same as above, right?)
- Set timing light to 22 advance and rev to 2700 RPM and time to TDC mark?
- Something else? (IMG:style_emoticons/default/rolleyes.gif)

I feel like an idiot asking this question. Timing is such a basic thing and I had no problem with the stock distributor and an old school timing light, but I've read more than one thread on how to time with the 123 distributor, plus I've also read that there's 10 degrees advance added at static on these distributors.
Help!

[914_teener]

Post a picture looking down the throttle body and where the hole is for the vac port of the TB. For ported the hole should be on the atmosphere side when the TB plate is closed.

[rjames]

Post a picture looking down the throttle body and where the hole is for the vac port of the TB. For ported the hole should be on the atmosphere side when the TB plate is closed.

I'm not using vacuum for advance.
My late TB only has a port below the butterfly for vacuum retard, which is connected to the distributor. Throttle body is from a '75.
Seems odd to me to time the engine to the 27 degree mark when max advance on the dist is 22 degrees. Wouldn't that make it too advanced at idle?