Has anybody fitted a "123" distributor ignition system to a Sprint.

I installed one on my sprint. Works a treat.

OK, so it works on a Sprint, does it / will it work on a Stromberg carb. engine? if so what timing setting did you use? When I`ve looked at the web sight they do not show a skew gear for the drive only a sort of peg drive, thats why I`ve discounted fitting one, but I would be interested in fitting one to a engine that I have.

Regards John.

Southern Carbureters have quoted me a price with a gear ready to fit.

I need to know how well it works and if my tacho will still work. ( have heard of some problems )
Ray

I do have a tacho. as a spare, that can accomodate (hopefully) this or a similar dizzy with a electronic system in the spares locker!!. Thats why I posted the query. I am running on `points` at the moment (no problems with maintenance or tune that I know of) but I would possibly like to move to electronic ignition if I was confident that I was not causing myself problems.

John.

I have a spare dizzy with luminition optical eye and beam chopper fitted but no black box.

Ray

Raygray:

I looked into the 123 Ignition pretty thoroughly, but ended up recently purchasing a Pertronix unit instead. Part of the problem for me was sourcing one with the correct drive gear at a reasonable cost, and the potential problem of returning the unit overseas if it did not work. Also, cost was a factor as I was quoted on the order of $1000 CDN for one from Europe. The Canadian distributor has not not done a Lotus TC yet, but I see they are now showing as available from some of the suppliers in Europe, although the part number call-up is at best vague and non-standard between suppliers. This made me hesitant to order one unless I could see it first.

A few tips from what I found; note I am not expert in ignition by any means, just trying to figure it out as well.

Here is a link to Stevew's old Lotus site. I believe he has moved on to Jaguar in earnest after the car was in an accident. Anyway, a few photo's and comments on the 123, including his own conversion to the correct drive gear.

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

There is some info in the archives of folks who have installed the unit and got it to work. Try a search on "123ignition". No real clear "how-to", but might help and provide confidence that it will work OK.

My car is originally Stromberg with Federal vacuum retard, converted to SU's with vacuum disconnected. With Stromberg's, I would recommend getting the Vacuum advance model and giving it a try. One can just block off the vacuum port and hosing if it provides too much advance in the mid-range load conditions. My understanding from the archives is the vacuum advance feature does not work so well with Weber's, but the Stromberg carburetor is suited to this feature.

I saw a couple of curves in the standard array that looked close to what Rohan had posted here as recommended advance curves for a Stromberg car, the H&H curve, Lucas curve, and numbers from the literature. From archive posts, it appears there is some doubt in the numbers, and the TC will work with minor variation in the curves, so exact selection and tuning of your engine may take experimentation with several of the provided curves and various static timing settings.

I graphed the available 123 curves and compared to the curves posted in the archives. Group 2 at 10 to 12 static or Group 3 at a more modest 9 static appear to be where you want to be. I didn't have the vacuum advance info at the time, but it looks like it will work well providing more advance in the midrange. Closest curves I found were 7, A, and B. Question is how they will behave with vacuum advance and do they provide a tight enough range to maximize the tuning of the car. Ideally we could get a series of 8 curves for the Weber and 8 curves for the Stromberg flashed into the unit to provide a perfect curve array, but my sense is the manufacturer is not really set up for this type of custom work.

I got in touch with the guy who provided most of the curves for the British engines. His name is Marcel Chichak and here is his own web site. Steve had also got help from Marcel when he was installing his unit.

http://starchak.ca/

Marcel is a very knowledgeable enthusiast/hobbyist, and lives reasonably close to me. Not sure if he has the ability to flash curves into the unit, but I was hoping I could get this done when he assembles a unit for me. Google up his name with Lucas; he has done some excellent articles on British ignition. Anyway, he got the 123 to work well with a Lotus TC, but the guy he was working with wouldn't give the prototype back because it was working so well! My project with Marcel seems a bit stalled; maybe this spring when my car is running I will revive it a bit. Noter he is not a supplier of the units; I was hoping to just get some tuning assistance this summer when I get back on the road.

For the issue with the tach, I believe this can be resolved successfully by simply powering the 123 unit separately from the coil positive lead which provides the pulses to the tacho. Explanation from our archives and the 123 forum seems to be that electronic ignition units damp or alter the pulses from the coil, confusing the Smiths RVI tacho. The electronic ignition ends up powered by a "hot in run and start, Unfused (white)" lead from your stock white fuse box supply or directly from the ignition switch. These approaches are electrically equivalent, just a question of ease of adding the wire to your car. This is how I intend to wire my Pertronix, which have had similar tacho issues reported. I found the postings on this issue on the 123 forum very confusing in the details, but this appears to be what they are getting at if you wade through it a bit. Note I have not got my Pertronix working yet, so your experience may be different.

HTH Sorry for length.

I have just fitted an electronic ignition module to my S2 supplied by www.ignitionparts.co.uk. It is a simple module to replace the points and condenser. It is supplied for use on Negative cars only (I changed mine over in an hour and sent the tacho away Speedy Cables to be converted) Ignition car parts offer a free fitting service to your distributor and all you have to do is slightly modify the base of the rotor arm to clear the trigger unit and then time the engine and off you go. I Emailed them from their site and gave them my distributor model No and they confirmed they could do it and off it went. The module costs £35 (when I bought it) plus VAT & postage. It works very well and starts first time and revs very cleanly. Granted it cannot be programmed like the 123 distributor but are you really going to notice that on a road car. To me it is fit and forget (especially in an annoyingly difficult position under the carbs) and is a fraction of the cost of other units which are ultimately doing the same job.

Adam.