Distributor to Distributor-less Conversion

Just wondering if anyone has any experience of converting an early VHPD engine with distributor and Mems2 ECU to distributorless setup with Mems3 ecu (using wasted spark coil in the head setup)

Err I wouldnt have thought that a Mems3 would have the correct calibration…

Other than that it is simply a matter of using the correct loom and coilpack(s).


Hi Dave, I was counting on you answering :slight_smile: The engine is being used in an MG Trophy ZR race car and we use a specific mems3 remapped to 190, we all have to use this ecu. My main concern is how do I remove existing distributor/ blank it off. Regarding wiring loom, the engine is being transplanted to an MG ZR with existing mems3 loom.

I am also looking at doing this conversion on my Exige race car, I understand the emerald can do wasted spark ignition without distributor, would there be any gains / benefits doing this ? Thanks Tony

Just undo the cap and remove it, then remove the flash shield behind the rotor arm, then undo the rotor arm retaining setscrew and remove the rotor arm, this will leave around 25mm of rotor arm spigot protruding from the end of the cam, if this gets in the way of mounting the coil, hacksaw it off…


Cheers Dave

Dave, another area I need to clarify. The later K series with coil pack ignition I understand uses a cam sensor in the rocker cover and this isn’t the case on the earlier K series engines with distributor. Aside from sorcing later cam cover and cam sensor do I need to change the cam itself or does the sensor work with older cams by momitoring cam lobe itself. Cheers Tony

If the Mems 3 doesn’t get a signal from the cam sensor it simply ignores it and reverts to grouped injection rather than sequential, the nett impact is minimal. The signal comes from a halfmoon lug on the cam which may still be present on late EU2 cams. If it is not there then so real harm will be done.


Thanks Dave