electronic ignition 123 question?

[96witton]

I have read all that I can find on the subject and two things don't get answered?
1. is there or is there not a spring at the bottom of the disruptor? it is only mentioned in the tech. manual section no one ever mentions changing it?
2. dose the 123 disruptor replace the transistor ignition?  on a 1969 280sl.
thanks in advance for everyones help.
Jim

[Kevkeller]

On my 1970 280 SL I kept the transistor ignition if I remember correctly.

[Cees Klumper]

Since the 123 is a fuly integrated ignition, I think it should/would work perfectly without any of the old external electronic hardware still attached.
I installed my 123 maybe 15-20 years ago and don't remember whether there's a spring at the bottom.

[Facelvega]

The 123ignition ignition completely replaces the original distributor and includes all other parts of electronic ignition. Make sure to buy the 123ignition with a vacuum connector.
However, I recommend buying the 123ignition TUNE, as this allows you to reproduce the Pagoda's ignition curve exactly.

A high-performance ignition coil should also be installed and the resistor in front of the ignition coil should be bypassed.

So far I installed about 10 123ignition and they work perfectly without any problems.

regards Alfred from Germany

[WRe]

Hi Jim,
I assume your car is still equipped with the Emission Control System (ECS). The Transistorized Ignition (TI) is part of this system and suggests a connection to the ignition system. However, the TI only provides the revs  (>1450 RPM) for an ECS relay (No. 50, see ECS). In this respect it is independent of the ignition especially of the 123.
Furthermore, the ECS does not control emissions but simply switches off the fuel supply in certain situations.
...WRe

ECS: https://www.sl113.org/wiki/Electrical/EmissionControlSystem

[Jonny B]

When we installed the 123 in my 250 SL, we did use the spring. My understanding it is there to put a small amount of tension between the bottom of the distributor dog-ear and the unit in the engine.