Work is progressing well on the wheel frequency calculations. I've created a spreadsheet that Pete and I are both using to determine how much stiffer the springs will need to be for the given downforce my DJ wings are going to produce. I'll still need to go testing, but it will hopefully guide us in the right direction.
I'm just reviewing the springs fitted to the front and rear shock absorbers, to decide what sort of rate I should change them to, to compensate for the downforce from the DJ Wings. I came across the following table in the User's Manual, which should allow me to identify whats fitted, and what my options are for upgrading. The run sheets from when Radical raced the car shows that they swapped between the 88 N/mm (500lb) and 106 N/mm (600lb)springs, but the car came with a very large selection of spare springs, so we'll see whats available. I dont want to make the car too stiff, or it'll be harder to drive, so we'll have to try a few different ones out and see how the handling changes.
The second attempt at making a rear wing bracket is now complete, using the 50% thicker 6mm aluminium sheet. I've retained the 10mm aluminium tubular structure that I'd had made for the first bracket. The key was to mount the tubular structure as low as possible to the gearbox mount, as that was where the bracket was flexing. I can still displace the wing by pressing down on the end plate, but, its far more rigid than before, and with the wire ropes fitted to the diffuser, these will help stabilise the wing further when travelling at speed.
With the wing bracket now sorted, I just need to check the spring rates fitted to the front and rear dampers, and see what came in the box of spares from Radical, as I'll probably fit the next hardest springs I have, to help combat the additional downforce and prevent the car from grounding out.
I popped over to Curborough last weekend to watch the orange sister car being put through its paces by Pete Goulding. Pete recently bought a front and rear wing kit from Elite Carbon, and on the very first outing at Blyton the weekend before, the new rear wing broke. Pete had gone for a dual element design, 1400mm in width, similar to the standard rear wing design on both cars. However, after climbing over 100mph, the lower wing couldnt handle the deflection from the total downforce that both 1400mm wings were producing, and it sheared at the point where the wing mount was bonded to the lower wing. Pete had to remove the new wing and refit the original, as it wasnt something that could be repaired at the trackside.
Pete has since taken the wing assembly back to Elite Carbon and they're working on the replacement. It should really have incorporated a vertical strut, to distribute the force from the top wing, on to the lower wing mounts. Or the lower wing needed to be made far stronger to take the combined loads. So for Curborough, Pete was running the standard Mygale rear wings, keeping the Elite front wing on the car, and he was suffering understandably from oversteer.
Still, he finished well at Curby (or Cowborough as some people like to call it) and scored enough points to place him 5th overall in the 2017 HSA Championship. I only finished 26th this year, fourth in class, as I was concentrating on the British Sprint Championship, and it's hard enough to commit to one championship, without having to worry about the expense of competing in two. All credit to Pete, he's had a great year, with several FTD's, even with the lower engine power output compared to mine, but I'm still improving, I beat him once, and we had a 1-2 at MIRA, and in 2018, with both cars running uprated aero, it should be interesting to see how much higher we can place in both championships.
Over the winter, Pete is planning on replacing his Pumaspeed Turbo (X37), possibly with a Turbo Technics Revo like mine, and he's aiming for more power than me, naturally. I reckon my Mountune engine could take more power, but to be honest, its proven 100% reliable, and I'm interested in seeing how the performance changes with the aero, before I plan any more power upgrades. My engine only runs 1.2bar to make 313BHP, and the low pressure helps keep the intake charge temperatures down, which prevents the engine suffering from detonation. I'm told that the SBD EcoBoost engine runs over 2.5bar to make 350BHP, which seems to me to be a bit on the high side. But I'm sure with a bit more boost, the Revo turbo/Pro-Alloy intercooler combination on my engine could easily see it reach over 340BHP. I'll let Pete be the pioneer this time ;) and I might just go back to NMS for a small tweak in the Spring to raise the power levels.
For now, its time to go testing, then I'll take the gearbox off for its bi-annual service with MBR, and then wait until March next year for the first round of the 2018 BSC. And in the interim, work on my fitness, and keep my eye in with some simulator work. I want a permanent Top 12 number in 2019, so 2018 is going to be a challenging year.