Electronic Ignition

[Ianashdown]

My newly acquired project won’t be delivered for 2 weeks, more on that once it’s safely in my garage, so I’m spending some time planning and scheming! Get way ahead of myself most of the time, but it’s good to have time to do some detailed investigations.

I want to keep the car visually near original, or at least easily returnable to original appearance, so this factors in to all my thinking.

If appearance and cost were not an obstacle, I think I would like to go with the Jenvey Heritage throttle bodies and one of the compatible ECU’s. I think that would probably give the best possible results of performance, driveablity, etc although I realize that it may take considerable time, effort and cost in dyno testing and map development. Almost certainly beyond my budget in addition the the total restoration the car already needs.

So my thought is to have the carbs properly rebuilt, and tuned once we get to the dyno. Then I’ll need to find a suitable ignition system. My research so far seems to suggest that 123Ignition system is the ‘state of the art’ today, although I’d be happy to hear of others, if there are any. I like that the basically standard appearance is retained and the advance is programmable via WiFi/Bluetooth. It seems that this should allow a better optimized advance curve, possibly allowing for some performance opportunities, more later. I don’t like that it uses a Rotor Arm. In my ideal world it would use an optical or some other sensor.

So the question is: Is this the latest and best system currently available, within the previously stated constraints? Assuming the use of available US pump fuel, does the improved ignition curve facilitate slightly higher compression ratio without the known consequences?

I should probably describe my plans for the engine at this point. I’d like to build an optimized/blueprinted engine with a moderate power increase, 135-150 HP but keeping reasonable but sporty road manners. I like engines that have lower rotating mass and have that rapid RPM rise and fall, and the crisp response of higher CR. Sort of like a semi-Race/Rally engine but with milder Cams for driveability. I’m not sure at this point whether to keep the cc at 1600 or go for 1700+/- depending on the condition of the various components at strip-down.

I’d be really grateful for any comments, suggestions, ideas, and experiences of the group on my potential plan, concept and general thought process. I should say that I am not an advanced engine guy, typically I’ve been more chassis and aero, but I’ve successfully re-built many engines and gearboxes over the years, but changing the specs is something quite different.

Thank you,

Ian
SoCal

[mbell]

I am very happy with my 123. While it does have a rotor arm it is I think optical triggered.

I am not sure on the compression ratio question but us premium has it's quite high octane so can run/benefit more advance. So having it be programmable is very handy. Been that the good quality and the immobiliser function I think it's a breast solution short of full ecu.

[miked]

Possibly opened a wide view here Ian.
To pay £399, I believe, for a properly programmable dizzy and still have a rotor arm and dizzy cap would not be my choice. Probably be slated here for saying this. I would use a Nodiz and wasted spark Ford coil pack and get the benefit of TPS and temperature parameter factored in. To get the best of anything you would want to RR tune. Especially if you are going to fork out on engine work to perhaps 1700 cc. You have gone off piste there anyway requiring individual type RR tuning.
I had better not saying about the usual carbs. Lotus police already have me on the wanted list for crimes against originality.
I have bike carbs that never loose setting. Cheap as chips. As are the bike throttle bodies. Can even use the injectors from the bike and the TPS.
Joking apart, it is down to the indivudual and your mind set and whether you are into originality or don't mind upgrading. Mine looks like an Elan but has a Zetec 2 litre.
Sure is nice to drive. Sale value not really my bag, long time dead. I like it.
Mike

[Ianashdown]

Hi Mike,

Don’t worry about the plain unmarked van outside your house . . .

I have an insatiable desire to try to improve everything, I guess it’s the engineer in me!

What I really need is another project that I can do alongside this one, but modify everything and feel no guilt! This car is a numbers matching S2 so I strongly feel a responsibility to keep everything original, or at least be able to go back by refitting the original parts. I already have the engine for the ‘other’ car, un-assembled as yet, new block, 83.5 bores, long stroke crank, Carrillo rods, CP pistons and hot head build for me in England. I’d like to do a full Fuel Injection and ECU system.

I’m on the lookout for an rolling chassis or an unfinished project that could be the ‘other’ car.

Ian

[Ianashdown]

Hi Mike,

I looked in to the Nodiz setup. It looks quite useful! If I could hide it well enough, even have a dummy Distributor, this might be a solution.

I’m going to research this a bit further.

Thank you,

Ian

[Andy8421]

Then I’ll need to find a suitable ignition system. My research so far seems to suggest that 123Ignition system is the ‘state of the art’ today, although I’d be happy to hear of others, if there are any. I like that the basically standard appearance is retained and the advance is programmable via WiFi/Bluetooth. It seems that this should allow a better optimized advance curve, possibly allowing for some performance opportunities, more later. I don’t like that it uses a Rotor Arm. In my ideal world it would use an optical or some other sensor.

I have just purchased a '123tune+' bluetooth dizzy. Very well made. Timing position is via internal magnetic pickup from a rotating disk mounted where the points would be in a normal dizzy, the rotor arm just switches the coil output between the four plugs. Haven't installed it yet, but I powered it up and the bluetooth connection was immediate, and the app seems intuitive. A number of threads on here with 'get you going' advance curves and advice for this product.

If you want to do away with the rotor arm, then you need multiple coils or a multi coil pack and for that you need a crank position sensor and some sort of controller. It all starts looking looking a lot less original. While there are good fire prevention reasons for not wanting a spark beneath the carbs, a rotor arm is about the simplest, lightest and most reliable way to switch between the plugs.

FWIW, my thinking was that it looks original, does away with the points and mechanical advance/retard, allows the curve to be easily programmable for tuning, and a particular attraction was that a PIN can be set to disable the distributor as a security feature.

Better than a switch in the glovebox.

[h20hamelan]

+1 for NoDizz, my plan
Though the theft deterrent is a real + for 123.

As you are in the good old US of A, you have Patton Machine, look them up on FB. Then, you also get Barometric Pressure Altitude compensation.

[elanman999]

I'm with MikeD on this, mapped ignition is the way to go. But I'm bound to say that, I've had full EFI on my Elan for nearly 10 years now. No fiddling with the carbs or dizzy , just jump in and drive!!
Cheers
John.

[Ianashdown]

I'm with MikeD on this, mapped ignition is the way to go. But I'm bound to say that, I've had full EFI on my Elan for nearly 10 years now. No fiddling with the carbs or dizzy , just jump in and drive!!
Cheers
John.

Hi,

I would definitely go for a full ECU managed system if it weren’t for the originality issue.

Ian

[elanman999]

Ian, OK fine.

Quite some time ago there were pics on here where someone fitted the ECU and coil pack behind the dash and then just bought the HT leads through the bulkhead and down the plug tunnel.

Cheers
John

[Ianashdown]

I did wonder about that! Having a non-functional distributor would help my need for original appearance.

Not having my car here yet, I couldn’t gauge how much room is available. Some of these ECU’s are quite small these days!

Thank you,

Ian

[miked]

My Nodiz is hung out of sight under the glove box. Out of the weather and heat. Only a small box with the benefit of flashing leds to confirm coil signals. Very handy when i diagnosed drop out with low voltage after too much cranking.

[RichardHawkins]

Ian,

I am not sure you can see the distributor with the carburettors in place. I am going with Megajolt, also attached to the side of the glove box, my coil pack will be hidden underneath the air box, but some people have mounted the coil pack where the distributor used to be. I found the price of Jenvey heritage throttle bodies very high, and when a friend said “it’s not an Elan without Webbers” my decision was made.

There is a man in San Francisco called Keith Franck, he runs a web site called sidedraftcentral. Keith is a retired physicist and has done much work on improving Webbers, his customers speak highly of his improvements. I am pinning my hopes on Keith when I get my engine running.

Hope this helps,

Richard Hawkins

[Ianashdown]

I think you're correct that the Distributor can't 'easily' been seen with the carbs in place, but a determined 'anorak' will certainly be able to see that they are missing.

I remember Franck from back in the Yahoo Groups.

My Plan was to have Mike Pierce do the rebuild on the carbs and another friend at Mountune do the Dyno and set-up. I sort-of agree that an Elan should have Webbers. At some point if you change too much, you're not experiencing the true Elan.

Ian

[Andy8421]

At some point if you change too much, you're not experiencing the true Elan.

Ian

Ian,
I think you have a good point. I have been wrestling with the same question. Taken to the limit, you end up with a modern car - at which point you might as well have just bought a modern car. In my case, I have decided to make reversible modifications to improve the reliability and safety, but leave the rest as is. So at the moment, the list is:

Electronic dizzy (security, reliability and ease of tuning)
CV rear driveshafts (safety and IMO improved driving experience)
Alternator (reliability)
Radiator (reliability)
Decent headlights (safety)
Roll over bar (safety)

I'll keep all the original bits in a box should an eventual new owner wish to reverse these changes.

As an ex electronic eng, the wiring of the Elan puts my teeth on edge, inadequate fusing, crappy connectors, poor quality everything else. The rats nest behind the dash with unfused connections is a disgrace. I had originally planned to redesign the system, use a homebrew loom and do the job properly, but that really isn't reversible, so I may stick with an original (replacement) loom and try to do the best I can with what is there.