Lotus Elan and Lotus Elan Plus 2 Forums

Hi all,

I think the scatter on my dizzy is now so bad that some real work is needed, and I like the 123 systems (installed in the XI). One problem I've found is lack of correct drive system from the jack gear shaft, rather than the usual peg type system. I've searched here quite a bit and found some custom conversions, but without much/any details.

Does anybody know if 123 have a twinc system or any details on converting the drive?

The Ford Kent unit doesn't seem to have advance curves that are right for the twinc either, if I have to convert one, does anybody know of a unit that matches the factory curve better? Or performs better than the factory spec?

Cheers,

Dave

I had to look up what a 123 ignition is and found this page that shows they have it. http://www.123ignition-conversions.com/Makes%20Types.html Let us know how it works out.

Dave:

I couldn't get Fred's link above to work directly this evening. However, you can get to it here:

http://www.britishsportscars.nl/Index%20eng.htm

and then select the correct button.

I contacted Hebel's by email a while ago (January 2010), and they quoted about 425 Euro's for the TC set-up. This was for what he called a 25D4 dizzy with gear drive, angled cap. Delivery time was two weeks. I got the idea from the photo's on the web site you will need to spec out exactly what you need for the TC and it is not a shelf item.

For the curves in the dizzy, he did not specify. As it is billed as a conversion, I assumed this would be the standard 16 curves they offer in the unit.

You are correct that a bunch of the curves are ill suited to the TC. I graphed them all and compared to a number of recommended curves posted here (Weber & Stromberg) and the curves in Wilkins. There were I believe two or three that looked to be close. If you want, I can look for the spreadsheet for you. Reading the archives, it seems the engine will work well on several different curves, so found the topic a bit confusing.

I also extensively Googled the topic (we have long winters here!). I came across a useful name, Marcel Chichak, who you can find on the web here:

http://starchak.ca/

Marcel apparently assisted in developing a number of the curves for the 123ignition for British stuff. He has some very comprehensive papers up regarding Lucas dizzy's, servicing, converting springs, etc. He is about 100 miles from me. He thought he could build me up a unit from parts in his garage, but we kind of lost contact & interest in the project. He got keen on other stuff, and my car was not running at the time. Anyway, Marcel had got one working well on a TC; so well the guy would not return the proto-type! Here is an additional link to his proto-type info:

http://www.tdcperformance.ca/


I was hoping to take the curve info I had collected and see if Marcel could build up the unit to TC gear drive & angled cap, and then complete the project by flashing in 6 Stromberg curves and 6 Weber curves. This would be very cool. I am not sure if he has the capability to flash in new curves; this is when we lost contact.

Another source of info on this project idea was Steve Waterworth, or stevew. He used to be active here, but has moved on to Jaguars. I traded some email with him last winter, and he mentioned he converted the stock drive to gear drive himself using a Burton gear and custom shaft. Also needed to add a thrust washer I believe. Here is a link to his archived site for the Lotus; it also has a spreadsheet with the various curves graphed up.

http://www.steveww.org/lotus/page145.html

Long story short, I decided to go Pertronix from Ray at rdent.com for about $340 US (edited to correct price, Stu) including the coil & new wires. Car works OK with this. No idea what the advance curve is though

HTH Definitely post results if you install one.

Decided to go with an Aldon kit (just replace the points & condensor) - Hoping the centrifugal weights are balance... I doubt it is likely on a 110,000 mile dizzy!

Edit: Hopefully it means my advance curve is still correct too, but will have to find out when it comes to tuning it.

Well, I finally got to the dizzy yesterday; it already has a lumenition system fitted (magnetic)! I guess that explains the bouncing rev counter from what I have read elsewhere on this forum. I did think the bouncing was down to the timing, I still think it probably is.

The metal casing of the dizzy is split where somebody fitted the lumenition system badly and the cap looks pretty original so maybe one of these is to blame? My other thoughts are it could be the mechanical advance or the coil.

Any ideas?