The shift lights give a visual indication of the optimal time to change gear in order to keep the engine in the power band. Various manufactures produce these but I opted for the Aces SureShift 2 product given the excellent reviews, extensive configuration options and because it is the chosen version for factory built cars.
The product comes in two parts - a control box (used to configure the unit - to be placed anywhere with reasonable access) and the lights unit (provides the visual indicators - to be placed somewhere in the peripheral vision of the driver). The control box is wired into the 12V electrical supply and into an ECU output that provides the tachometer signal. The latter is already provided in the standard 420R factory loom under the dashboard, near the ignition switch.
If the light unit is to be mounted on the scuttle, and the control box mounted somewhere under the dashboard, then a hole must be drilled in the scuttle to allow the connecting wire to pass through. However - the connection is made by a standard DIN plug which would require a 25mm hole to be drilled. To drill the hole, the windscreen would need ot be removed. To do this, the first step was to disconnect the two wires that connect the heated windscreen elements - found underneath the knee trim / fusebox on both sides of the car. Another strange Caterham quirk is that the connector is too large to pass through the chassis hole and must be cut off. Then the chassis bolts can be carefully removed while the windscreen is being supported.
Disconnecting and cutting off the heated windscreen connector; Windscreen off
A cardboard jig was made up to mark the placement of the bracket for the light unit, and the corresponding mounting points. The scuttle is thin aluminium sheet bent over a tubular steel frame that also supports the dashboard. Probably overkill, but because the scuttle is quite fragile, I decided to mount the bracket with bolts passing through it and into tapped holes into the dashboard support frame. Roundhead M3 x 20 bolts were used to secure the bracket in place.
Bracket template; bracket fitted
I wasn't comfortable with the idea of drilling a 25mm hole in the scuttle to pass the light unit connector through. I decided to drill and grommet a hole to accomodate only the diameter of the wire. This would mean dismantling the light unit, unsoldering the connections, and drilling a 5mm hole in the scuttle. Once the wire was threaded into position and trimmed to length, the connections were then soldered back into the light unit.
Preparing to desolder (noting wire colours); cutting cable length; re-soldered unit
The control unit was fastened with velcro tape to the bulkhead and connected to the loom via the available spade connectors. The windscreen was re-mounted on the car and Waygo connectors used to reconnect the heated elements.
While the light unit was disassembled, I removed the plastic facia that carried the OEM branding and replaced it with my own "Tigger" version!
