Classic Jaguar World - A Far From Pointless Excercise

Jim Patten gets fired up over electronic ignition

One of the most common problems on both Entente Cordiale runs have been distributor points closing up and failing condensers. Electronic ignition, of course, consigns the lot to the scrap heap. Ray Ingman at Classic Spares has been a great fan of the Luminition Optronic ignition system for some years, running it on both his road and race cars.

His company have now become distributors (how appropriate) for the Jaguar application and so he continues his soap-box praise. Not entirely convinced, we checked with a few other people around the trade and found the likes of Geoff Maycock of Autocats equally impressed. As the system requires absolutely no drilling or alteration, maybe it was time to fit it to my 'E' type - who knows what I might have been missing? Rather conveniently, Classic Engineering, run by Martin Pike and Barbara MacKellar, is located at the same address as Classic Spares and so l was able to pick up my Luminition at the counter and simply take it to their workshop for them to carry out the installation.

The basic idea of the system is to replace the conventional distributor points with an infra-red beam emitted from an LED diode to a photo transistor. An interrupter, or 'chopper', with (in the case of Jaguar), six segments chops across the infra-red beam interrupting the circuit, performing the same job as the points. The pulse created, passes to a power module which switches the existing ignition coil on and off. Simple, really.

Sparks fly

If you were doing this job at home, you would first familiarise yourself with all of the components, work out where they all go, and do a dummy run. Martin Pike however, knows about these th ings and just got on with the job once the battery had been disconnected. Firstly the old points were removed and thrown into the bin. The water-proof shroud is removed too. As the points pivot post on the distributor base plate sometimes needs to be trimmed the whole base plate has to be removed by undoing two screws and freeing the spring attached to the advance/retard diaphragm. The plate was taken to the bench where the post was cut down using a hacksaw.

The optical switch fits in the space vacated by the points with the wires passing through a grommet, shaped to fit the cutout in the distributor body. Now the chopper is placed over the distributor cam and pushed down, checking that the blades pass through the optical switch. The instructions in the kit suggest that the power module is screwed to the bulkhead but Classic are one ahead of the game here and supply a bracket to fit around the side engine frame - still no drilling. Some tape is wrapped around the frame to protect the paint and the module screwed to the bracket. The snap connector from the module to the optical switch in the distributor can then be pushed together.

The original wire from the distributor to the coil is now redundant, replaced by that from the optical switch to the power module. A brown wire coming from the power module is connected to the negative terminal of the coil. The other wire, a red one, is connected to the positive side of the coil to join the main feed wire. Martin took the redundant wires and taped them back into the loom rather than snip them off. Should I ever decide to revert to conventional ignition, then the correct wires are there.

The new wires were neatly gathered up and secured back out of the way with a cable tie. This will be replaced later by the correct Jaguar loom tie. Finally, the original rotor arm was replaced and the distributor cap fitted. In the unlikely event that i would want to revert tot he original system, I could do so wit no problem.

It is recommended that the makers ignition timing be used (10 degrees btdc for the 'E'type on 8:1 pistons) and the spark plugs set to the original gap of 0.025in. Martin checked the timing just in case it had moved and then I was back on the road.

Over the coming months I will be monitoring the performance and cold start. But the first immediate gain is the fact that it's maintenance free. Changing the points on an 'E' type is not so bad but what about the XK engined saloons they're a real fiddle. The shopping list for my Mk1 has just been extended. Classic Spares stock the complete range of Luminition products including a reliable replacement for that vexatious 'Opus' system used on the V12.

Martin Pike makes ready to fit the Luminition electronic ignition system to our 4.2 'E' type.

Enclosed in the kit is the optical switch, the 'chopper', power module and necessary wiring. An extra for the 'E' type is a clamp for frame mounting.

One of the problems associated with ignition points is the wearing away of the heel causing the gap to close up. This, and the burning of the contacts, makes their replacement by another system all the more desirable.

The original contact breakers are discarded along with the condenser. Then the base plate can be removed after releasing the two retaining screws.

To allow the 'chopper to pass through the optical switch, the points swivel post may need to be trimmed down to size. A small file cleaned up the raw edge left by the cut.

The optical switch fits neatly on the original base plate with the wires fed through a neatly shaped grommet to exit through the distributor casing.

The interrupter, or 'chopper' is pushed firmly down the distributor shaft making sure that it passes through the optical switch without fouling.

A bracket secures the power module on the side frame without the need for drilling making a neat job of it at the same time.

A multi-connector joins the wires from the power module to the optical switch in the distributor. The brown wire from the module runs to the negative terminal on the coil, replacing the distributor to coil wire while the red wire picks up current from the positive side.

PRICES:

Optronic, for early 6-cylinder (featured here)	Ł95.00
Performance, for early 6-cylinder (includes high energy coil), XJS 3.6, late Series 3 XJ6	Ł165.00
Optronic, for pre-HE V12	Ł165
Performance, for V12 HE	Ł180
Performance, for pre-HE V12 (includes high energy coil)	Ł230
Daimler V8 application	coming soon!

For more details contact: Classic Spares Ltd. Unit 4 Brook Road, Britannia Road, Waltham Cross, Herts EN8 7NP. Tel: +44 (0)1992 716236. Fax: +44 (0)1992 788424. Classic Engineering carried out the installation and can be reached at the same address or on Tel: +44 (0)1992 788967.

Lumenition is available from Classic Spares Ltd