I was wondering if the Marelli distributer can be replaced with a Lucas distributer?
I was hoping to modify the Lucas with a Crane system.

 

Do you mean (a) can the entire Marelli ignition system be replaced by the Lucas running a Crane?

Or do you mean (b) can the Marelli distributor ONLY be replaced by a Lucas and the rest of the Marelli ignition system be kept?

Greg

 

The distributor mount on the V12 engine block never changed so both the Lucas or Marelli distributor will fit.

Also, in case you were not aware, the Lucas distributor includes a vacuum advance and mechanisms for a centrifugal advance. The Marelli distributor does not have anything for ignition advance. It is empty, containing only the rotor.

The difference is in the ignition electronics. You cannot mix the electronics between the Lucas and Marelli systems. Whichever distributor you use you need to have the appropriate electronics.

 

The only thing I have to offer, on page 164 of "The Book", K.P. talks about switching over from Marelli to Lucas.

 

Indeed he does. But it is a solution that involves keeping the Marelli electronics and using a Lucas dizzy in place of the Marelli one. However, because the Marelli electronics fire the banks separately (hence the use of the double height dizzy and rotor), the Great Palm's fix requires something called an automatic coil selector, which is meant to magically switch between the spark sources according to where the Lucas dizzy's 12 post sequential rotor is pointing at the time. That is switch many thousands of times a minute on a continuous basis, proportionately with the revs.

The automatic coil selector is not designed for this continuous operation (I believe it is designed to switch to a second coil in the event of a failure of the first one, as a racing belt and braces idea). I have only read of one person trying it and the ACS failed in about a week, as did the replacement.

Greg

 

I would say going back from Marelli to Lucas wouldn't be too much of a problem, going the other way involves a little more.
Not to Hijack the thread but would it not be better to go from say Marelli to something like MegaSpark and just run coil packs, no distributors or parts that can seize, also advantage of full spark at top revs and a larger spark plug gap to boot! sounds like the way to go.