MSD ignition question for 400i

Hi,

I have been running a MSD 6AL ignition box (not the new version) for many years. Is uses the trigger from the original Hal sensor on the distributor. The MSD box is connected direct to the wiring from the original Dinoplex unit and sits where that is supposed to sit. The car runs a Blaster 3 coil in original position.

Its a 400i, so single distributor and injected.

The box was ordered for a 12 cylinder engine back when, but I think the only difference to a standard is that the rev limiter is at the correct revs for a V12. Now it is set to 6k RPM's.

Anyway, the car feels a bit hesitant below 3k RPM but once over it pulls harder. That is right where the MSD goes from multiple sparks to single spark according to their specs. With a standard V8 unit maybe that would be lower at 2k RPM for a V12 and maybe not as sensitive.

Anybody else with an MSD box experiencing similar behavior?

Can in be faulty Hal sensor or interference from the coil to the Hal lead? The cable is original and not shielded.

Can it be a faulty distributor, ie not moving advance enough. If so, how is that checked and/or cured? Is there a need to lubricate anthing inside of the distributor?

Plugs & HT Leads are good, so is rotor and cap (ie new).

Is there a alternative to MSD that does not do multiple sparks at lower RPM's? Maybe the engine does not like
sparks over a wider cam angle?

The reason for popping up now even if I have had the MSD box in the car many years is that I have not driven her so much as the car needed new fuel pumps, filters and accumulators which is now replaced with new units on both sides.

All input much appreciated

Kind regards
//Rob