electrical and ignition 123 Ignition Distributor....any Info Or Personal Experience?

[jimk]

What the setting in post 221 doesn't consider is that at low throttle openings (light load, lower rpm) the carb advance advance vacuum  opening is not puling vacuum.  You have your vacuum hooked on that port, yes. And on side drafts, the vacuum profile is not the same as on a downdraft carb.

[Beach_Bum]

Sounds like a jetting issue to me.  Have you bumped up your idle jet to the next size to see if that helps?

 

Ah man, I don't even have the time to go down that rabbit hole again. Hahaha I think I finally settled on a 55F9 after trying what seemed like every combo known to man.

 

Had same issues but i drilled second progression hole bigger on mine weber 40DCOE19 and replaced 50f8 with 50f9. And 123tne helped a lot with backspitting but occasionaly at low rpm there comes stumble too...

 

Yeah, I'm running the 55F9 too. At least I'm not the only one who's ocassionally stumbling

 

 

I'm guessing since nobody has snickered at my advance curves that I'm within reasonable operating conditions

[rstclark]

OK  installed the 123 tune  with the consensus curve.

 Basically a TII  curve with vacuum at 10 degrees static,     and I have to say it's better than the IE tii distributor I was  previously running. NO disrespect to IE for their product , it's very good.   Low end  pull is better especially.   Haven't even tied to tune it yet, so chances are it could get better for my motor ( more  details re the motor if you are interested)   OK, Fresh rebuild  M10 9.5 compression, 284 cam 32/36 jetted well,  IE shorty header , balanced  with some intake porting

Big problem is that after installation the tach doesn't work.  yikes !! 

It's wired  correctly by instructions . The second curve works  etc.

 

 So    ---   Why is my tach dead  ?   Anyone else have this issue ?     

 

Rob

[Simeon]

Have you got the black wire connected at the coil -ve terminal?

[williamggruff]

I've been led to believe that a higher compression motor requires a lesser spark advance than a lower compression motor, but I've not found much detail regarding the specifics of the decrease in mechanical and/or vacuum advance, nor have I found any detailed guidance related to the profile of the cam.  My motor's compression ratio is 10.1:1, and my compression numbers are 197, 194, 195, 195.  I'm running a Schrick 292 cam, and have recently installed a Weber 38/38.  Exhaust is an IE long tube street/track stainless header into the early IE stainless dual resonator and muffler.  

 

How might I go about calculating predicted values for the mechanical and vacuum advance curves?  Are there general rules of thumb that I should follow?

[rstclark]

Simeon

 

 I hooked up the black wire to the negative side of the coil where the previous distributor was connected.  Is the black wire the key connection for the tach ?

[rstclark]

Wikkiamggruff

 

Read all 12 pages of this topic and you will see some good curve suggestions.  Start with the Tii curve for centrifugal.  max out 34 degrees at 3,500 rpm  and pick one of the vacuum curves for a similar motor  Because of your high compression you might start with a static timing of 6 or 7 degrees

Once the distributor is installed, you can hook up the laptop  In the tune setting, you can adjust the timing up 5 degrees or down 5 degrees  one degree at a time from your base point to see how it works. You will have to note your adjustments and reset your curve to match the best setting.

[jrhone]

I have the Bluetooth version arriving this week. It's an advance test unit. They say they are a few months from selling it still. I'll post my findings in this thread or maybe start a new one specific to that unit.

[Simeon]

I have the Bluetooth version arriving this week. It's an advance test unit. They say they are a few months from selling it still. I'll post my findings in this thread or maybe start a new one specific to that unit.

Well, merry Christmas! How did you swing that?

[Simeon]

Simeon

 

 I hooked up the black wire to the negative side of the coil where the previous distributor was connected.  Is the black wire the key connection for the tach ?

The Tach is driven by the coil primary back emf from the collapse of its field when the voltage is disconnected from the coil. The tach is connected via the black wire to the points connection which then connects the points to the coil negative. Depending upon how you have your 123 connected, you may need two wires connected at the coil negative. One from the 123 which is switching ground and the other is the old black wire which would be also disconnected at the distributor.

[rstclark]

So basically the black wire connected to the negative side of the coil signals the tach how fast or slow the coil is discharging and the tach registers this as RPM Yes ?

I have no idea how to connect a second wire you describe  Obviously the negative side of the coil, then to what ?  A straight connection to the tach  ?

By the way  the black wire I'm using from the negative side of the coil goes thru a kill switch before going to the distributor and it works, but this shouldn't change anything . It worked before on the IE distributor. Does the 123 tune with it's own ground wire change things ??

[Simeon]

Realise that it is easy to confuse the existing black wire from the car wiring to the black wire from the 123. The existing black wire needs to be terminated on the coil negative terminal along with the black wire from the 123. Coils usually have multiple blade terminals for exactly this purpose (they are fitted on the stud / nut).

This existing black wire is connected to the Tach, going via the connection at the distributor which will be disconnected with the 123.

[rstclark]

So the original black wire should run all the way to one of the negative terminals on the coil.  Then another black wire should run  from one of the other negative terminals to the 123 distributor

 

[xferboy]

Big problem is that after installation the tach doesn't work.yikes !!

 

No worries, there is a rev limiter built in

 

I'll second the you need two wires running to the coil negative (tach & distributor).  If you pulled an IE tii distributor and replaced with a 123 (as I did), the hook up should be very similar.  If I remember correctly, red/black to the coil, blue (?) to a chassis/engine ground and yellow to a  "no connect"(open)/12v switch.

 

If I remember correctly from installing the IE, my tach signal (black) was picked up at the distributor (2 connections on the distributor), and another black connected to the - on the coil.  I jumped (extended) those two wires together to get a tach signal, as I connected the distributor directly to the coil.  I couldn't tell you if that wiring is factory, or messed up by a random previous owner.

 

Hope that helps

 

Allan

 

p.s re: bluetooth:  I'm interested to see how that works.  Please report back.

[rstclark]

That's Funny   yeah there is a rev limiter 

Found it. the  black wire has a spare terminal near the distributor I wasn't using before,  but plugged in a new wire and ran it to the negative side of the coil,   And  ITS BACK

 

So nice to have the tach    

 

Thanks for ,the help