Fixing Timing with a 123ignition distro?

[lobf]

Hi there folks- 

 

I took the daily driver out to the store this morning, and noticed on the drive that my ignition timing was way off. I'm currently getting an older '02 back to road-worthy status, and have gotten pretty proficient at fixing engine timing with the old distributors. 

 

However, my daily has a 123ignition distributor on it, and I don't know what to do with that. Is it the same process of rotating the housing and setting points? Can anyone give me a broad strokes guide about how to adjust timing with these things on a 2002? 

 

Thanks! 

[chargin]

Usually I tuned mine on the 1-2-3 bluetooth Phone app, not spinning the unit, once it was happy I didn't change it much on my Tii 

 

 

[lobf]

Woah are you saying I can "rotate" it through the app? I get out my timing light and my phone and do it like that? 

[Stevenola]

You need to physically verify that the 123 curve matches the actual timing on the flywheel.  For example, if your 123 timing at idle is 10 degrees BTC, you must take a timing light and confirm this is the same at the flywheel.  Get a dial back light and set it to 10 degrees (or whatever your curve is) and rotate the distributor until the TO ball is in the window (not the Z ball).  This will confirm your timing is actually what the curve says it is and you're good to go.  Also, you should bracket your idle timing by a couple hundred rpm to avoid any idle fluctuation issues, for example if you want to idle at 10 degrees advance at 950 rpm, make sure the graph points are 10 degrees from 850-1050 rpm.

Edited August 2, 2023 by Stevenola

[lobf]

22 minutes ago, Stevenola said:

You need to physically verify that the 123 curve matches the actual timing on the flywheel.  For example, if your 123 timing at idle is 10 degrees BTC, you must take a timing light and confirm this is the same at the flywheel.  Get a dial back light and set it to 10 degrees (or whatever your curve is) and rotate the distributor until the TO ball is in the window (not the Z ball).  This will confirm your timing is actually what the curve says it is and you're good to go.  Also, you should bracket your idle timing by a couple hundred rpm to avoid any idle fluctuation issues, for example if you want to idle at 10 degrees advance at 950 rpm, make sure the graph points are 10 degrees from 850-1050 rpm.

 

Okay copy that- do I need to remove the valve cover and rotate it in to TDC and all that like I was setting initial timing, or can I just run it as-is and adjust until the timing is better? 

Edited August 2, 2023 by lobf

[Stevenola]

Run as is and verify the two are equal

[lobf]

Okay thanks Steve- 

 

and maybe I should be clear about what's happening in case my assumption about timing is wrong: suddenly today the car was not running smoothly, the cylinders never sounded in rhythm, and the car would sputter if I gave it too much gas. I suppose once I see if the timing is proper I can move on to other solves, but I'm not the most experienced mechanic so I figured I should see if maybe my first assumption is different from yours. 

[lobf]

Okay so I pulled up the daily driver ('76) and went out to the '71 as a reference for the location of the timing marker on the block, since I've re-set the timing on that thing a half dozen times and know it well now. 

 

When I went to have a look though, I'm realizing I think I was checking the marker while everything was disconnected, and I was looking through the area that the radiator would cover. 

 

My daily has an electric fan, so removing the radiator means removing the fan too, and this is starting to feel like a hassle, or a project I need to dedicate more time to... I'm considering letting the shop have a look instead... 

[Preyupy]

There is a hole in the transmission bell housing right by the starter that can be viewed from above.  There are marks on the flywheel.  There is OT (this is TDC cylinders 1 and 4)  and there is a metal ball imbedded in the flywheel which is 25ded BTDC.  This is much easier to see and much more accurate than trying to use the mark on the front pulley and timing cover.  

 

[Hans]

Timing doesn't normally suddenly change by itself.

[Son of Marty]

3 minutes ago, Hans said:

Timing doesn't normally suddenly change by itself.

Depending on gravity field fluctuations.

[popovm]

22 hours ago, Son of Marty said:

Depending on gravity field fluctuations.

 

Ha! I guess your timing would technically retard if you swung by a black hole, but I guess the piston time to TDC would also slow down. Sounds like you'd be ok. 😁

[Cabbage Fumes]

There is a baseline procedure for the 123 that isn’t in the manual. The initial setup that is in the booklet that talks about rotating the body until the green led lights up is only to get you to a point that you can start the car. You need to verify timing beyond that, and I don’t know why it isn’t outlined in the manual but kids these days, right?

Once you are confirmed at tdc and green lit, make a baseline curve in the app. A straight line from 500 to 8000, an advance number that you can verify, I use 12°. Set a digital timing light to 12°. Key on, start the app, write the baseline curve to the 123. Using the source of timing (pulley or flywheel), confirm that the number you chose for the baseline matches tdc mark with the timing light. Rotate the dizzy body if necessary to line up the tdc mark. This will verify that the dizzy is in the correct position before setting up your curve. Don’t forget to change from the baseline to your desired curve!