Once you install the 123ignition, the Emission System is immediately affected:
• Because the Speed-Relay loses the RPM feed from the transistorized ignition;
• Because 123ignition recommends connecting the vacuum line from the manifold to the distributor.
My questions are:
1. Without RPM info, what happens to the Speed Relay and the Relay-box?
2. If you remove the vacuum line from the Two way valve, the Emission System becomes ineffective. Should one keep the vacuum line from the Two-way-valve against vendor recommendation?
3. Is the Start-Lock switch working after these changes (does it prevent the engine start when gearbox is not in “P” or “N”)?
Many thanks
Francisco
Dear Francisco
Interesting topic the one your are bringing up today.
I once refurbished a wiring harness with emissions control on a car with similar characteristics as the one you have, so I had the chance to study what the emissions control system does.
The emission control has a loop of conditions which once all met, the fuel delivery to the injection pump is cut momentarily to the FIP via a fuel cut off selenoid.
As far as I remember, the conditions were on a manual transmission car that:
1. IDDLE switch was closed, I mean car was not under acceleration
2. Car was on 3rd or 4th gear
3. The clutch pedal was not depressed
4. And finally that RPMS were under a certain range so that engine can be easily restarted by itself without user noticing once fuel delivery is resumed.
Now…. Answering your questions
1. Without RPM info, the emissions control harness will be inoperative
2. Without vacuum to the two speed valve….. I guess that without vacuum the two speed valve will not be able to change the timing of the distributor. I think that is what that valve does on the emissions control system.
3. Start lock switch. The start lock switch, the one that inhibits car start from engaging the starter selenoid if car is not in park or neutral position has no relationship with the emissions control system. Is totally independent. So I do not see why that will stop working.
And finally…..
The RPM signal can be obtained somewhere else, not only from the original ignition control module…..
Just connect that cable which is green (with and external coaxial jacket to shield signal against electromagnetic interference) to the NEGATIVE POST of the ignition coil.
Any RPM meter takes always its signal from that point.
And …. In any case what the emission control system does is not very important in practical terms. It is much better to have a better controlled ignition system via an 123ignition distributor, than keeping the original aging distributor which may be not precise nowadays because of the wear of its internal parts.
Having the spark on the right point/moment will alleviate many of the pains of an old classic car. You will have much better combustion, which translates is less gas mixing with the engine oil (un-burned gasoline end up in the oil), and that means less wear to your engine.
