Elan +2 and 123 Ignition

[syrius]

HI

I install an electronic ignition on my +2 TC
http://www.123ignition.nl/
the signal from this device is not the same than the older ingnition.
The manufacturer said that is necessary to update the Smith thacometer from RVI to RVS
Have you somes experiences about this trouble and a way to resolve this problem ?

thanks in advance for your help

Serge

[jimj]

Yes, I sent my tacho to Speedy Cables in Wales to be converted. About ?55 I think.
Jim

[syrius]

Thanks

Do you known witch type of upgrade there are made ?

Serge

[paddy]

The tachometer needs to be converted from RVI to RVC. This involves changing the internals of the tachometer, specifically the electronics for detecting ignition pulses and converting them to a voltage that drives the needle.

An RVI tach is wired in series between the +ve supply and the +ve of the coil - all coil current passes through the tach and RVI electronics, and it detects the pulses by sensing the current change. The problem is that electronic ignition systems work differently and generate a different shape current profile and the RVI detector doesn't work. It is also possible that the RVI electronics, since they are interposed between the actual +ve supply and the coil, interfere with the supply in some way that causes problems for the electronic ignition module.

The RVC system instead is connected to the coil -ve (or "points") terminal. The +ve supply to the coil is direct. The tach electronics work by detecting voltage changes at the coil -ve terminal, and although there will be differences, this is essentially the same waveform for points and electronic ignitions. This means that the tach will work with the electronic ignition, and the tach won't interfere with the operation of the ignition either.

After you've had the tach converted there will be minor changes to the coil and tach wiring to make it all work.

I haven't used Speedy Cables but plently of people here have, and have been satisfied with the results, and they will definitely know what needs to be done. I believe they can also refurbish the tach so it looks like new.

Paddy

[syrius]

Thank's very much Paddy for a very interesting technical explanation .
i will send my tacho to Speedy cable .

serge

[Old English White]

Thank's very much Paddy for a very interesting technical explanation .
i will send my tacho to Speedy cable .

serge

Et voil? !
I am happy to read from you on this forum Syrius ...
As I told you few hours before , there is allways someone ready to help , explain , etc.
One day , you 'll be more on LotusElan.net than everywhere else ...
Christian.

[kcrossle]

I sent both my tach and speedometer to Speedy as part of my Zetec conversion. Besides doing the adaptation, the guages came back looking like new. Impressive.

Keith

[syrius]

Thank's very much Paddy for a very interesting technical explanation .
i will send my tacho to Speedy cable .

serge

Et voil? !
I am happy to read from you on this forum Syrius ...
As I told you few hours before , there is allways someone ready to help , explain , etc.
One day , you 'll be more on LotusElan.net than everywhere else ...
Christian.

HI Cristian

Yes I apprecie well the conviviality of this site, many passionate persons , is a big source of information for me.

Serge

[syrius]

I sent both my tach and speedometer to Speedy as part of my Zetec conversion. Besides doing the adaptation, the guages came back looking like new. Impressive.

Keith

thank's for your experiences Keith
I send an e mail yesterday to Speedy cable ;
i'm waiting for an answer

Regards

serge