Lucas electronic ignition. Tacho modifications

[holywood3645]

I have a Lucas Constant Energy ignition system I would like to use on my elan. I was told the Tacho would need reworked to operate with the new ignition system.
Have any of you modified your tachs to work with a voltage sensing electronic ignition system?
what was involved? any idea of price.

I just had my tach refurbished and really dont want to butcher it, so i will be looking for a spare to use.

Thanks
James

[UAB807F]

I bought an old one from Ebay which was listed as "not working", but the all-important face & glass were ok and I intended to fit modern internals. I used an aftermarket rev counter, stripped them both down and used the modern internals in the Elan casing. The Elan needle fitted the modern spindle and until you look round the back you can't tell. (well, you can, this one doesn't jump all over the dial ) The modern internals were much smaller than the original Smiths circuitry, so plenty of space and it's an easy modification.

It took about an hour or two all in with just holes to drill in the rear of the casing to mount the new mechanism. My costs were low because I'd had the modern rev counter for a while and I think I only paid ?25-ish for the Ebay one because it was sold as spares/repair. I'd guess the biggest cost will be labour if you want a specialist to convert it. But if you can build model kits and have patience then I'd urge you to DIY, it's not difficult at all, just attention to detail.

Brian

[bob_rich]

Hi James

Provided your inductive pick up tacho ( Usually marker RV1 ****) is in good order it should be fine with a Lucas Constant energy system. ( I have one on my 7) The trick ( that worked for me) is to put the inductive pick up in series with the coil only (CB or -ve terminal or SW or +ve terminal) rather than the +ve feed from the ignition switch as this usually goes to the electronic module and the coil +ve or SW. I think the small standing current that the Lucas module takes for its electronics upsets the RV1 style tacho. This does mean adding some wire but cheeper than a reworked tacho.

Hope this helps best of luck

Bob

[prezoom]

When I converted my Elan to an alternator based system, I had a local speedometer shop in San Diego, convert the tachometer. Also changed to points to a Pertronics at the same time. The biggest problem was re-routing the wire through the loop on the back of the tach. Once I got that right, have never had a problem, except for a loose ground on the back of the tach. Oh yea.... and all the little knurled nuts that hold the instruments in the dash that I have dropped and are somewhere, never to be found again. Thank god for a lathe, the appropriate tap and knurling fixture.

Rob Walker
26-4889

[holywood3645]

Rob was the Shop called foreign speedo in North Park?
James

I live in Oceanside just north of San Diego

[ericbushby]

Hello James,
I bought a ULTRASPARK unit from Ignition Car Parts in the UK. I believe it was part no. ICP EKO 18
This worked OK without any mods to the tach. or the wiring.
This conversion set is intended for use with the 23D4 distributor.
Hope this helps.

Eric in Burnley
Type 45 S3 SE 1967