The heart of the installation the ecu modifies the signal to the Ford Edis ignition
module, altering the advance dependant of engine speed and load.
Usually supplied as a module, fitted with brackets, along with a communications
cable and 16 pin Molex plug with pins.
FORD 36-1 TOOTHED WHEEL
The Megajolt system requires a 36-1 toothed wheel to be fitted to the engine. My
preference is to install it to the crankshaft damper as a “Ring Gear.” By maching
the damper a little, this makes sure that the gap between the ring gear and the VR
sensor remains the same.
FORD EDIS IGNITION KIT
Consists of an ignition module, coil pack, and crank position (VR) sensor.
Usually supplied with the original connectors aiding in the assembly off the loom.
TIMING IT UP
For the Mi16 I use the threaded holes in the sump to mount a bracket made of 4mm
aluminium angle, I mount the sensor first to be inline with the centre of the trigger
wheel, then drill and tap the damper to secure the timing wheel. Find Top Dead Centre
using a DTI gauge and then make sure that the missing tooth is 90 degrees ( 9 teeth)
ahead of the crank sensor. Then all is paint marked to check for any movement / creep.
MAKING THE LOOM
I use the EDIS connectors supplied with the coil pack to manufacture a loom to mate
all the EDIS, Megajolt and Throtle Poistion Sensor components up. All joints are
sealed with heat shrink, taped and then have an outer sheath of either spiral binding
or brand new conduit (preferred). I use Military Grade Sheilded cable for the crank
sensor, and EDIS to Megajolt Connections.
I use a single 40 Amp relay, wired with thee fused outputs, 5 Amp for the ECU, 25
Amp for the EDIS kit, and a 15 Amp spare which could be used for a fuel pump (mine
is). The loom is completely stand-alone and only requires a switched igntion constant
12v and an earth, two earth rings are fitted to the loom, however all earths for
the whole loom are connected to both earth rings.
Three wires are provided to connect to the TPS if it is not being done by me, one
is a 5v Reference, one and earth and the other is the signal wire - usually green,
the voltage on this wire back from the sensor, increases as the throttle is opened.
As very few TPS sensors come with a connector, I tend to attach three wires to the
TPS sensor, and install a 3 way AMP SEAL connector. Using this conector also enables
modification to the signals seen by the Megajolt if required.
PCMCIA CARD - Optional
I quite often read of issues with USB to serial converters, I have been using one
of these adaptors on my HP non serial ported laptop for ages and it works great.
VRSSIM - Optional
I have built and use the VRSSIM hardware and use the software to test all looms I
make and installs I do. No loom leaves me without a full check and test on my test
bed to make sure the install is as easy as can be. I can also supply the VRSSIM
hardware, to enable users to test their install.