Sadly I’ve had a bit of a week work-wise and didn’t get into the garage till yesterday. I did manage to get my race licence medical done and my licence application sent off. Sadly BGH Geartech didn’t have a replacement upright in stock so as a temporary fix I decided to attempt to straighten the old one. Basically the bottom rear corner had got bent in. It was only when I came to stick it in the vice to assault it that I spotted the crack. As Tim Hoverd has pointed out cracks really don’t show up well on these black powder coated chassis and parts which is why his are all grey. So plan B was to whack it straight and then weld it up. It seems the things are about as tough as a piece of chocolate anyway so it should do temporarily.
The welding went OK after a fashion, it’s thick steel so I turned the welder power up to max. And promptly welded my wire to the welder tip. I got there in the end and after a bit of a gentle caress with the angle grinder and a lick of hammerite it was looking good to go. While I was at it I painted it’s opposite number which has been a goldy plated colour since it was replaced after the original one on the nearside got bent at Oulton.
I’d decided a while ago to stick my original 3.14 Sierra diff in. Since it’s rebuild by Austen’s Dad it’s really looking quite spiffing having been blasted and painted and the 3.14 ratio just suits the Busa engine’s power delivery better than the 3.38. The 3.38 has a bit more backlash than I’d like too. So after sticking some oil in it I then got the diff bolted back into the chassis.
And that was it until today. Trouble is after getting back from London at 8pm Friday then working overnight both Friday night and last night I’m a bit cream crackered and not exactly firing on all cylinders. I started getting the offside rear corner back together, first refitting the drive shaft, it’s amazing how much easier it is with no wishbones in the way! This was accomplished fairly quickly, followed by replacing the wishbones (glad I made a note of where all the washers go on the rose joints!). The wheel bearing got repacked with grease then I bolted the hub back onto the upright and got the upright refitted.
I came to the conclusion as I slid around Silverstone in the wet that my car was set up too hard so I’d decided to change the springs for softer ones. My current setup is 225 pounds on the front and 250 pounds on the rear. The originals when I built the car were 225 front and 180 rear and firming it up definitely got rid of the wallowy rear end. Tim helpfully has measured all the pickup points and stuck them in a spreadsheet to calculate suspension frequencies and according to this mine are in roughly the right ratio but are just a bit too stiff. If I drop to 200 front and 225 rear I’ll be about the same as him frequency-wise so that’s what I’m going for. After a bit of faffing about with luggage straps and a vice I managed to swap the springs over OK.
By the end of the afternoon I had the rear suspension reassembled, shocks back on, brake calipers and handbrake cable refitted and she was looking much more like a car again. As you can see from the pic here not only is the car looking better but there are quite a few less bits on the floor underneath now.
I now need to refit the propshaft, fuel tank and reverse motor, then swap the springs at the front and apart from the usual stuff I’d do before a race weekend that’s about it. First race is 2 weeks today at Snetterton, a bit of a long trek for a single race and of course I’ve yet to finish a race there so it’s not exactly my favourite circuit.