Hi
I'm contemplating fitting 123 onto my Ami 8, but I notice there is a choice between normal 123 and the 123 Evo. The evo system has a vacuum advance take off.

Has anyone ever fitted these and is there any gain over the standard 123 system?

Cheers

Matt

I dont like 123 personally, seen too many fail.

I know albert will fix them, usually FOC, but i dont really like the way that are not too 'tuneable' either, they seem flat at top revs to me.

All just opinion, and im sure they are a great product as so many have been sold and used succesfully.

I must say, I had a 123 fitted to my car, after I heard lots of amazing claims from owners who had fitted them to their car. It's ok, but certainly not amazing, I'm sure a properly set-up car on standard points & condenser would run better and certainly start better. I fitted one to my car, because of condenser failure leaving me stranded on the M6 in the Lake District, the car has been a hell of a lot more reliable, since it's been on 123.

My experience with the unit i bought for one of my dyanes and 3 units fitted in succession to one particular car ive worked upon and one or two other random cars i know.

Unless the battery is very good, they dont seem to work well and therefore, dont start.

And the 3 units on one car mentioned above were all failures.

I can only comment on what ive seen, im sure there are hundreds if not thousands of cars running perfectly on 123.

Matt,
by advancing the ignition timing under conditions of high manifold vacuum, that feature of the Evo would, or should, give even better mpg on those occasions when you're driving with a light foot on the throttle pedal.

However, if you drive 'Adrian style', it's rumoured that those moments may be few and far between ...

ken

That is due to the fact that when our engine is "loaded", driving with the throttle more open in respect to the engine RPMs, the mixture volume is higher and richer, so to prevent the engine from knocking the ignition time must follow the "basic" advance curve of the 123.

In the case of low or medium load, the throttle is barely stepped down ,a fast intake flow causing vacuum in the 123 sensor indicating that a timing advance of up to 10º can be added to the basic curve. This vacuum advance is restricted to be added when revs are at least 3000 RPMs, as I can recall.

Anyway, the main issue with the 123 is that of installing it among with the low impedance VISA brown coil, in that way is when we realize the advantages of this electronic ignition system.

Regards.