You may remember from a couple of issues ago that I’d started to put the suspension together, using the new race-spec upgrades that would be needed, but I got side-tracked after fitting the hubs and uprights and turned my attention to fitting the engine instead. Well, now the race-ready YB is all bolted-up, this month I’ve gone back underneath to finish off the suspensions and braking – but this involved a lot more than just bolting everything in place. Starting at the front, before I could fit any of the lower control arms or roll bars, firstly I needed to add a couple of small strengthening plates to the chassis legs where there new anti-roll bar mounting blocks would fit. The factory chassis has an indentation, but for optimum performance (and reliability) the new Group A roll bar mounting blocks really should be mounted on a flush surface. So, a strengthening plate was soon welded in place, primed and painted, and ready for the front-end to be assembled.
The new lower control arms mount from the crossmember to the bottom of the new alloy hubs, while a secondary piece connects that bar to the anti-roll bar bracket. The bladed anti roll bars themselves then connect to the lower control arms via a droplink – everything is adjustable, rose-jointed, and all interlinks with one another to give precise and accurate control of the suspension geometry – it’s one of the biggest differences, if not the biggest difference, between the RS500 road cars and the BTCC racers. To finish it all off, a new set of AP Racing four-pots were added with new 330mm x 32mm floating discs too.
Then, it was time to turn to the rear. Again, the mounting points for the anti-roll bar brackets were the starting point… mainly because they don’t exist at the rear! Unlike the fronts – which just needed strengthening – at the rear complete new ‘towers’ were needed to offer mounting points for the Group A bladed-style rear anti-roll bars. Once welded to the chassis legs, primed, and painted, these provide a stable base on which to mount the rear anti-roll bar brackets; the bladed arms attach to each side of the rear beam while a tube runs across the width of the car connecting everything together. Again, the rear brakes needed upgrading, and again AP Racing four-pot calipers are added along with 315mm discs – although this time a tad narrower at 28mm wide.
With that loot all back together, I just managed to find time to tackle another job this month… one that has caused me a fair bit of apprehension. Why? Because it meant cutting two whacking great holes in the side of the car! I am, of course, referring to the two fuel fillers that needed fitting to the rear quarters. Unlike the previous system – which was filled from inside the boot – the race cars require a proper motorsport-spec filler in each side. So, after measure, marking, more measuring, and yet another quick measure-up, I fired up the drill and jigsaw and cut the required holes in the rear quarters. To say I was relieved when everything slotted into place was an understatement! Now the fillers are all connected up to the tank, I can mark the fuel system off my to-do list. The list is definitely getting shorter, but so is the number of days before race day, so I can’t rest on my laurels and need to keep the pace up.