Seat Rails

This cpost covers chopping out the seat rails that came in the shell, increasing the tunnel width and welding in new FIA-spec removable seat rails. The original fitment of the seat rails had retained the central tunnel support which meant that I couldn’t mount the seats – there just wasn’t enough width between the sill and tunnel on either side. I’m not a motorsport engineer, but I was also concerned that the rails in the car didn’t have spreader plates.

Sometime ago I had bought a set of seat rails a few years ago, but by the time I came to fit them, the FIA had changed the specification in the regs. I realised this when I looked up the spreader plate specs and despite being part way through fitting the ones’ I’d bought, I decided to get a new set. Either way the original kit in the car needed to be chopped out and the tunnel plate support panel removed.

No need to take it out as one part, so it came out in sections….

There was loads of sand under that tunnel support plate on both sides, possibly from some sand blasting in a previous stage of work.

With all the old stuff out it was time to start putting the new elements in.

This meant suitable reinforcement to the top of the tunnel for the handbrake and the new spreader plates for the FIA spec bolt in seat rails. As I’ll need to do this on the Series 1, I made a jig for getting the spacing right between the seat rails. The new design makes much more sense. No reason not to get full penetration welds around all elements given that you can take the seat rails in and out.