Monday, 15 February 2016

FIA rollover bar

In preparation for doing some more enthusiastic track driving this year, I've upgraded my standard rollover bar to the trackday version. It's pretty much the same overall dimensions, but has a stiffening X of tubes included, and some tubes welded in to take the petty strut and a couple of headrest/pads.

Regardless of what you've read elsewhere, the metric trackday bar does fit the Caterham 160 boot cover nicely. No need for any modifications or a new boot cover.

The effect of the bar - apart from just being stiffer - is that its top is further forward, almost over the seat headrests. So the imaginary line between rollover bar and the top of the engine is a little higher, and your head/helmet is a little futher away from the critical line.

When fitting the bar, it can be muscled into place for the visible chassis fixings in the boot and on the top of the car. The extra two cap-head bolts need to be fitted from underneath, and to do that, the shock absorbers must be removed.

(In fact, these cap-head bolts are in the fixing kit that comes with the original rollover bar. Plus, the original bar also has captive nuts in the base - not mentioned in the manual. You may as well fit these even with the standard rollover bar. Can't hurt!).

Shock top bolt removed from behind the rear wall carpet. Still nicely covered in fresh copper grease


1600 miles of grime. Not in bad shape!


Each of the rollover bar bolts is torqued to just 20Nm. The shock absorber is then refitted and torqued as the in Assembly Guide.

When required, I will fit the petty strut, which attaches to the top of the new rollover bar at one end, and a ready-fitted boss in the chassis, hiding somewhere behind the skin on the passenger side...