Distributor Advance

[Galwaylotus]

Update: I took my distributor to the local Tech today and we ran it on their tester. The machine was a bit rough and isn't used much anymore but we were still able to get the advance profile. When I plotted it against the factory spec (same as Miles Wilkins' data) it exhibited a profile parallel to the spec but slightly offset. Considering the variability in the equipment setup I'm satisfied that for all intents and purposes my distributor mechanical advance is per spec. I took it home, installed my new Powerspark, and installed it back into the engine block. I've messaged Powerspark to ask if I can set initial static timing with the 12V bulb that I've used with points. It was late this afternoon when I sent the message so I hope to hear back tomorrow. When that's sorted, it will be time to install the freshly overhauled DCOEs and get it running! Unfortunately the weather forecast for the next few days isn't promising so that phase may be delayed.

[AHM]

Well that is reassuring - Can you correct the offset by advancing/retarding the timing?

[Johnfm]

I don't think you can set static with a bulb like you would do with points.

I think you need to approximate distributor postion (did you mark it or photograph it before removal?), then time it at idle usign a timing light.

[Galwaylotus]

Update: There's no update today. The weather has turned miserable here and I've contracted a bad headcold so no progress unfortunately.

[Johnfm]

I'm surprised it only took you 30 mins if you also did the "take distributor out, remove springs & wire weights up with binding wire" bit?

I would estimate about 15 minutes to unscrew old points, tap out the little pin in the dizzy shaft, remove springs and add wire, reassemble with electronic points. Maybe 20 minutes.

The wiring of the black-box, maybe another 15-20 minutes once I decided where in the footwell to put it, Wiring fed through the exisiting grommet into the engine bay to connect to coil and dizzy.

So, minus thinking time, about 45 minutes actual tinkering.

[Johnfm]

And the phone insurance company and explain bit!

Hagerty have no issue at all with electronic ignition, or alternators or updated headlight bulbs etc.

They only want to know about significant performance mods - which this isn't.

[AHM]

Agreed, electronic ignition is more to do with reliability and doesn't in itself alter the ignition timing - no problem.

But being able to tune the ignition timing can be a significant performance enhancement. I insure with Hagerty - did they tell you that tuneable ignition timing was ok? I'd be tempted if they did.

Edit - there are some good plots of the effect of ignition timing on BMEP on page 159 of Miles Wilkins book.

[Johnfm]

Optimising existing performance of stock head, cams and valves by using electronic ignition would unlikely be considered a performance mod. Phil at Hagerty had no issue with any of it.

Just set the curve to a be less conservative. A noticeable improvement in smoothness of delivery.

[Galwaylotus]

"Oh the weather outside is frightful ..."
I've had the carbs reinstalled for a couple of weeks and the static timing set as well. It looks like it will be the new year before I can try to start the engine considering the weather we've been having.

I wish everyone at LotusElan.net a happy and peaceful Christmas and hope all your Lotus Elan wishes come true!!!