I’ve been spending a massive amount of time working on the electrical system. I’ve retained a high-end German firm to design and manufacture a motorsport harness that will subsume the pile of sub harnesses that I have. More about them later.
Stefan was able to squeeze a one-week trip to Boston between the Rolex 24 at Daytona and testing at Sebring. We figured out where to mount all of the devices and he took measurements for the harness. He was adamant that all critical electronics must have vibration isolation. Apparently the flat-plane cranks in the LMP cars and certain tracks are really tough on even motorsport electrical components.
What’s better than a shop dog? Two shop dogs. Stefan hard at work.
The bracket below utilizes three vibration isolators to mount the dual Lambda to CAN module. Note that the automotive connector on the middle wire has been snipped off. It will be replaced with a bulkhead motorsport connector that mounts to the vertical tab on the bracket.
MoTeC LTCD and stainless steel bracket with three rubber vibration-dampening sandwich mounts
Three small tabs were welded to the chassis cross brace. They’re small and located on curve of the tube making it difficult to align them perfectly and prevent them from moving during welding. To solve that challenge I made a jig composed of a fixture plate and six aluminum spacers. The fixturing plate had to be wide enough to span the apex of the tubes. Once it was clamped to the bottom of the brace it held everything in place.
Welding jig: fixture plate, six spacers, bracket and three weld tabs
There’s a lot of electronics in the footbox; engine ECU, three PDMs, active damper ECU, two dual H-Bridges, EPAS ECU, parking brake ECU, etc., all of which need to be isolated.
Given how tight things are in the footbox, I designed two stainless steel brackets that utilize four vibration-isolating sandwich mounts. The left one mounts two PDMs and the right mounts the engine ECU and a PDM. Considering that those four devices run about $11k, it’s cheap insurance. In addition, the isolators have studs sticking out which makes it easy to mount the plate and they raise the devices 1/2” above the mounting surface which makes it easier to attach / detach the connectors.
Devices mounted to the right-side plate, empty left-side pate and a vibration-dampening sandwich mount
The plates are mounted to the side of the footbox behind the side impact bar sub frame. They are easily accessible and will eventually be hidden by a carpeted closeout panel