123 Ignition's 123/Tune Advanced Curves

[Andiamo]

I find all of this discussion to be utterly fascinating and now that I've read it I am convinced that I want/need to get a 123 for my 124. I have always hated the cheesy low-quality feel of the stock dizzy. The question now is "bluetooth" or switchable? Oh, and question number 2.) what coil are you guys using?

Many thanks to all of you who have contributed to this discussion (short of the "paperweight" comment).

cheers,

Mike D.

[Andiamo]

Well, because of this thread and the other research that I'd done along the way, I pulled the trigger and bought a 123 +4 (programmable via bluetooth) distributor. I installed it this morning [along with a new coil] on my L-Jetronic '81 engine. It took all of about 2 hours with the biggest challenge being removing the pin that holds the gear on the stock shaft. If this distributor were supplied with a gear already installed it would be a 1 hour swap. What an amazing upgrade, my engine loves the tune I created and pulls harder at every RPM. It's like I put a new engine in the car. It was expensive, but you really do get what you paid for. I'm certainly not saying that you 'need' it, but if you love your car and were considering one of these then you will not be disappointed. Comparing this set-up to the stock distributor and coil is like comparing Mercedes to Yugo. Don't listen to the nay-sayers, this is a very high quality piece of equipment and was actually a joy to install.

[Nut124]

Andiamo, great. I had the 123 on my shopping list until total project $$ price hit me a bit.

Can you tell me what your timing is?

1. Max advance/timing at full power, top rpm?
2. At what rpm does full advance come in?
3. Are you using vac advance?
4. If using vac, what is the vac advance curve?

The same can be accomplished by carefully tuning, adjusting a Fiat dizzy. Performance comes from correct timing not from the name on the dizzy.

I do think that improper ignition timing is a leading cause of perceived poor performance of these engines.

[18Fiatsandcounting]

I do think that improper ignition timing is a leading cause of perceived poor performance of these engines.

I totally agree with this. Way back in the distant past, I tried timing my spider by eye, using the marks on the cranks and timing cover. However, given the error in being able to accurately see the crappy timing marks on the cover, I was actually putting the timing at idle to 0 BTDC when it should have been 10 BTDC. Once I figured that out and timed it properly, the engine was much perkier.

-Bryan

[Andiamo]

Nut 124, my set-up is by no means perfectly dialed in. Although, it does run SO much better than it did prior to the dizzy swap. It's smoother, quieter, more responsive and seems to have more power and torque (S.O.P. dyno tested - Seat-Of-the-Pants). I'm also running a brand new 1.5 ohm coil.

My vacuum advance curve is a copy of the one FIAT142 settled on, mostly because I can't get my head around what it all means and it seemed logical that I should start out by using what more experienced people than myself came up with. That said, I'm considering plugging the vac ports and skipping that curve altogether, essentially not running any vac advance at all when I do my carb conversion..

My centrifugal advance curve started out the same as FIAT142's, but I made a couple small changes that seemed to make sense (to me and how my engine was responding).

RPM's --- Degrees of Advance, MAX RPM set to 6,000
500 --- 10
1,000 --- 12
1,500 --- 17
2,500 --- 24
4,000 --- 36
8,000 --- 36

After a few runs up to 5,500 rpms on this curve and not hearing any 'pinging' and no flat spots, I bumped the curved up 1 degree with the app's "tune" feature on my Android phone (ha, who would have guessed that would ever happen on a 1960's designed Twin Cam). I did that mostly because the engine idled better, but I think this increase also bumps up all the points on the curve and I wanted to see if there was any pinging yet - there was none that I could tell. However, I don't feel I need to go any more advanced either. The does not run hotter than previously, but it does heat up quicker. Most likely because of more advance.

"...Performance comes from correct timing not from the name on the dizzy." - If the design, quality, function and condition of the parts were equal, then I might agree. The original distributor on my car was a sloppy, antiquated (literally) example of low cost manufacturing. This 123, is far from that.


*** Disclosure: I DO NOT recommend to anyone that you take any of this gibberish as gospel - it is reference only. ***

Andiamo, great. I had the 123 on my shopping list until total project $$ price hit me a bit.

Can you tell me what your timing is?

1. Max advance/timing at full power, top rpm?
2. At what rpm does full advance come in?
3. Are you using vac advance?
4. If using vac, what is the vac advance curve?

The same can be accomplished by carefully tuning, adjusting a Fiat dizzy. Performance comes from correct timing not from the name on the dizzy.

I do think that improper ignition timing is a leading cause of perceived poor performance of these engines.

[Nut124]

Andiamo, is vacuum line connected to the dizzy now? Is it working. What is your total timing at idle?

Timing should be about 10deg w/o vacuum at idle. With a functioning vacuum advance, timing should be 20+deg BTDC at idle. The vacuum advance does improve power off idle. I would not disable it if it is working.