Hi Guys,

With more and more of us switching to the 123 Ignition distributor and all the questions coming up about how to set the curves on the bluetooth model, I figured I'd start a thread where we can all share tips and screen grabs of what works for our cars. I'll go first.

Jake_Raby taught me a simple method for getting the app and the dizzy in sync.
– First, follow the directions for installation (using the green light), which will get you to a point where the car runs.
– Set a curve point for 8 degrees @ 1K RPM, a point for 27 degrees @ 3000 rpm and a point for 27 degrees at 5K. Load that curve into the 123 distributor.
– Hook up a timing light, cap off the vac advance and rev the engine to 3K RPM. I like to aim at the notch on the flywheel. Rotate the 123 until you’re showing 27 degrees BTDC @3K and then lock the unit down.

The app and dizzy are now synched and you’ve approximated a simple stock curve. Now the fun begins. Drive around and see if there are any flat spots in acceleration. Make note of the rpm’s where the power seems to dip. Add points there to fine tune the advance. You’ll probably need a little more advance a little earlier. You may also need to tweak your idle advance a bit until it runs smoothly. Of course the condition of your engine, altitude and a bunch of other factors come into play. I live at 6,000 feet and here's what my freshly built 2056 with 9590 cam in my bumblebee is happy with: (Note that I've zeroed the MAP curve. I haven't been able to see a difference using it, but am still experimenting. If someone can offer suggestions for that, please do!)



Click to view attachment


I have a new unit for my ravenna car and will make a full video on that when I install it this winter. Will post a link in this thread when ready.

Thanks for this Ian - nice to have one place.

Thank you.

@iankarr In your above example, when you're in the "edit centrifugal curve" portion of the app, are you putting a value in for "Static Advance" in the "General" section above the "degrees crankshaft" section? If so, what value are you starting with?

EDIT: Sorry....just realized the answer to my question was in the first post! Sometimes it's the small things that escape me.

There seem to be a few 123 curve threads around, but I had previously bookmarked this one, so I hope this is a good place to ask...

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Picked up a 123 distributor (TUNE+ 4-R-V-POR-IE) in the recent group-buy, installed it last week, and have been getting out for a few test drives.
Overall initial impression is very positive and the changes are instantly noticeable, including smoother idle and much cleaner takeoff from stop.

I do have one issue haven't been able to make progress on, though.

Under modest-hard acceleration or steady load (uphill), I hear some pinking/pinging that I have never noticed before (windows are usually down). This is mostly in the 3~4k rpm range, but I might also hear it a little into lower rpms if lugging or higher rpms if I keep my foot in it longer. I have tried several different curve settings from extra mild (20* max advance) to fairly aggressive (30* max advance), and the pinging is always there (maybe just a little more with aggressive settings). I also don't notice a difference with or without the MAP curve enabled (as many others have mentioned).

I started out with a fairly full centrifugal curve (too many points, trying to be too clever)...
... but quickly moved back to a simple curve (like the one below, thanks @mgphoto ) that is much easier to make changes on the fly.


MAP curve is the one that was in the 123 as received and has been disabled most of the time.

I've tried moving the 500/1500 points as low as 0/2 and as high as 10/10, which seems to effect idle and startability (higher values = higher idle and harder to crank).
I've tried moving the 3500/8000 points as low 20/20 and as high as 32/32, which honestly doesn't feel much different (higher values = slightly stronger off the line and pulls a little harder).

I also tried playing with the "Tune" function on the App dashboard (very cool!), but that is almost impossible to do without a copilot and I didn't know what I was doing anyhow.
I noticed it did generate some info, but I haven't found an explanation for what it means.


So far, the pinging is still there in all cases and the usual rpm range.

Feels like I could be missing something obvious, but don't want to continue experimenting at risk of causing damage.

Any suggestions appreciated.

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A little background for context...

Car is a '73 2.0L with stock D-jet except for FJ67 injectors.
Engine is an older 2056cc build with lower compression 'dished' pistons.

Prior to installing the 123, the original distributor (231 174 009) was still in place, including a Compu-Fire ignition module that has been in there probably since the late 80's.
Bosch blue coil has been in use a few years (Ed said it should be OK).

Fuel in the tank might be 87~89 octane and might be a couple months old. I never really felt a difference between cheap 87 or expensive 91 and car seemed to run the same on any, so I was never picky.

-M

I wonder whether the MAP curve is actually disabled? You could try zeroing out the MAP settings in the program interface, and disconnect the vacuum line from the port on the side of the 123 disty (plugging the vacuum line to the intake manifold so you don't have a vacuum leak), and see if your pinging problem goes away.

Your centrifugal curve seems OK (although more advance at 1000 rpm would be better) and shouldn't be causing pinging. To eliminate gas octane as an issue, try adding an octane booster like Lucas.

And, carbon deposits in the combustion chambers can result in pinging.

Thanks for the feedback @Lockwodo

Quite certain the MAP curve was (and still is) disabled. Hopefully it really is off when "disable" is selected, without having to zero all of the points. That could lead to some confusing results.

I did do some more test runs after the previous post and ended up with the curve below.
With this setting, didn't notice any pinging while driving the same route as before and still on the same fuel.


Then got out for a long drive yesterday with some SoCal folks.
Never heard any pinging (though it was often kinda loud in the cabin) and car seemed to run pretty much normal.

I would like to try a little more advance around idle, but...
Right now the car wants to idle at ~1100 rpm (according to 123 app) after fully warmed up, which is why I set the advance constant from 500 to 1200. I think this helps with the steady idle. More advance seems to make the idle higher and if the curve is ramping in the idle zone, then the idle isn't as steady.

More advance at low rpm also seems to make it a little harder to start/turn-over. Maybe firing before the starter motor gets the engine properly spinning?

-M

A 2056 with dished pistons is not stock. So are they inverted dished or domed pistons?

Inverted dished, not flat or domed.

-M

I thought I would address a point or two for you guys. While I am no expert on setting curves there are some things you should know about the 123ignition.

First and foremost, always synchronize the app in your phone with the crank pulley. That way you have no erroneous figures in your timing curve. You can do it one of two ways. You will need a dial back timing light to be effective.
1) Pick a point in the app curve and verify it at the crank pulley using the rpm value in the app. If you don't see the point at the particular rpm then loosen the distributor and rotate it until you do.
or
2) Make a sync curve using the same degree value at all rpm points. The advantage here is you do not have to reach an rpm and hold it steady to get a reading. Start the car warm it up and confirm that degree point with a timing light pointed at the crank. If you don't see it then turn the distributor until you do. In both cases once you have synchronized the app with the motor all future changes can be done exclusively with the app. As long as the distributor has not physically been moved then what you see is what you get.

Second, the vacuum curve only works if you have a vacuum line connected to it.

Third the tuning feature is adjustable and is used as a stop watch to measure the time it takes for your car to go from one rpm point to the next. Normally you would do this in third or fourth gear with your foot all in.

Hope that helps
Ed

Thanks Ed that is a very good explanation.
I have a feature request, could we get the app to record data? This would be a great feature for tuning.
Just saying,
mgphoto

Thanks mgphoto and lankarr!

Should I delete my thread now?

Definitely liked the sync the app idea and had read that, was going to do it....but didn't put that in my thread.....

GN