12th March 2010

Pre-race fettling

All that the new airbox needed to be finished off was a bit of 100mm flexible ducting to connect the kevlar faceplate with the body of the airbox. Strangely, none of the usual sources - Demon Tweeks, Rally Design, Merlin Motorsport etc. seemed to do 100mm ducting but as usual eBay came to the rescue.

Entirely unnecessary, but one of those 'ah, what the hell' moments, was the decision to cover the bottom half of the airbox and the remains of the original airbox (on the far side of the picture, out of sight) in gold (well, goldish) foil. The idea, of course is to reduce the air temperature inside the airbox, which is why I haven't put any on the top of the airbox which is close to the inside face of the bonnet. Would it make any difference? Well, who knows, but it looks wickid, innit...

  On a slightly more functional note, I've added an extra set of Aerocatches on the top of the bonnet to try and stop it from bouncing up and down at speed due to the build up of air pressure underneath the bonnet. Obviously this is just curing the symptom rather than the real problem - the real problem being that there's nowhere for the air being rammed into the bonnet to go other than the rather small vents at the side. In the long term I still want to see if I can duct the radiator exhaust air out of the top of the bonnet, but in the meantime this will have to do.

With the four pairs of Aerocatches I've bought for the Furybird II, these ones mean I now own 7 pairs of Aerocatches. I'm thinking I should buy shares in the company...

The pins which the Aerocatches attach to are mounted to the horizontal panel on the scuttle. It was therefore fairly important to make sure the Aerocatches were in the correct places, as having one in a position which required the pin to pass through the steering column or the ECU located on the other side of the scuttle would be a tad embarrassing.

Because the bonnet pins supplied with the Aerocatches were about 10cm to short to reach from the scuttle panel to the catches themselves I made these little aluminium stand-offs. Yep, they didn't really need to be waisted in the way they are, but that's the problem with having a lathe - the good side is you can make stuff you couldn't before, but the downside is that you end up making stuff you don't
really need, just because you can.

Anyway, they only took the best part of an hour to make up...

  While I was chopping bits off the bonnet I also took the opportunity to trim the wheelarch return on the nearside front wheelarch as there were clear indications on the tyre that it had been rubbing. Mind you, I've also tweaked the positions of the sidepods as it turned out that they dipped down at the front, meaning that the bonnet wasn't flat, leading to the rather low ground clearance at the front of the bonnet. With the sidepods tweaked I've been able to raise the front of the bonnet, which will also help with tyre/bonnet clearance.

Once the holes cut for the Aerocatches and the wheelarch was trimmed I could give the bonnet a quick once-over with some more matt black cellulose, and cover up all the primer over the new air duct in the nose. The paint's a bit stripey, since I did it with a little touch-up gun which has a very small paint fan shape. Still, 'tis only a racer...

One of the problems I had at Snett in September last year was that the seating position wasn't quite right. The GRP-clad seat looked pretty good, and was very comfortable to sit in, but there was too much material under my thighs, with the result that when my feet were on the pedals my heals weren't resting on the bottom of the pedal box but were waving around in the air. It was of course perfectly possible to drive like that, but it made things like heal'n'toeing rather difficult. To resolve this problem I've made a new seat, and rather than covering it in GRP I've followed the usual course and covered it on gaffer tape. Although I've got 5 sq m of black Nomex material in the stores, so that may change...

With the old seat the shoulder straps for the harness were still slightly long. This could have been a good thing, because as you can see from this picture the harness mounting points on the roll-cage are nowhere near central when compared to the driver's cockpit space. Yet another example of crap fabrication by the welding-monkeys who made the chassis and roll-cage. The bosses for harness mounting points on the chassis are, however, in the right place (making it even more mysterious how they got it so wrong on the cage) so plan A was to mount the shoulder straps onto the chassis mounting points but have the straps go over the roll-cage bar which they mounted onto now. A fine plan, and the reason why half the bottom edge of the headrest which is just visible in the picture is cut away, but the new seat obviously moves the driver's fundamentals rather further forwards than the old one, so the shoulder straps are now actually the correct length when mounted on the roll-cage and are too short if mounted onto the chassis. Looks like I'll have to get the welder out after all and weld some new bosses onto the roll cage.

  Finally, one thing I'd noticed at Snett was that I had a great view of the nearside of the car in the rear view mirror, but very little on the offside, and the Racetech mirrors in all honesty aren't that great - there's certainly no reason in having a great big panoramic mirror on the rollcage if it's mostly showing me the grass alongside the nearside edge of the circuit. There wasn't much I could do to alter this with the original mounts, so I bought some longer ones (this one's twin is the bit holding the bullet camera in place) which allowed me to put a bit more angle on the mirror, giving a better field of view. It's still not perfect, but it's substantially better.

With all, or at least most, of the planned winter mods'n'upgrades carried out, all I had to do now was give the racer a bolt-check, re-fill the racer with oil, get oil pressure, fire up the engine, go to the petrol station to fill it up with fuel (giving an opportunity for a quick road-check to make sure the steering and brakes were still working as they should be), pack the tow-car with tools and spares, collect the trailer, load the car onto the trailer, and get a good night's sleep before heading off to Snett for Sunday morning's qualifying. What could possibly go wrong?  

14th March 2010

The 2010 season opens...

...with a DNF. Cock.

It's fair to say that the run-up to race-day wasn't exatly plain sailing. In fact, I nearly invented a wholly new entry in the Racing Driver's Big Book of Excuses - Chapter 4 - Not Turning Up. The problem was that with a few hours' fettling left to do on the Saturday, I suddenly discovered that the detachable tow-bar for the Scooby tow-car wasn't where I thought it was. Or, indeed, anywhere else in the garage. Or the house. Or anywhere. I came within a few minutes of announcing I wouldn't be turning up due to a lack of a tow-bar, before in a final roll of the dice heading of to The Shed to see if it was there. It was. The upshot of all this faffing around playing Hunt The Towbar meant I ended up loading the car onto the trailer at ten at night, after an afternoon of running around like a demented numpty. Hardly the best preparation for the start of the season.

Anyway, with tow bar located, the tyres on the trailer pumped up, the race car full of fuel and all systems good to go I head up to Snett at some ungodly hour of the morning. This was the first time I didn't have to go to a 'first time driver's briefing' as I'd raced at Snett previously, so after signing on I was at a bit of a loss. A nice cup of tea courtesy of Tim solved that dilemma. Qualifying did not go well. My best lap was a 1:22.xx which was much slower than I'd gone in qualifying in September, let alone the race. The car was running fine - indeed, it was running better than it had in September, with the oil temperature down to 110degC and the water temperature down to 95degC. Still a bit warmer than I'd like, but within the bounds of reasonableness. No, the only reason for my woeful qualifying performance was the fact that I had evidently forgotten how to drive a car. The datalogs show periods of several seconds at the ends of the straights when I didn't have my foot hard on the accelerator, or hard on the brake - just, not to put to fine a point on it, dithering. The result was that I qualified third last in 18th place, a long way behind people I'd qualified in front of a few months earlier.  


Not that it made a blind bit of difference really, but the only car problem was, as usual, the DASH2. I'd reconfigured the gear indicator with some more accurate numbers - the original configuration didn't take account of the fact that the rear tyres are 206/60/13s rather than the 185/60/13s on the front, and since the rear wheels are the driven wheels, that's a relevant consideration. However, the gear indicator seemed to work better as a random number generator between 1 and 6 than providing a useful output. At one point it was claiming I was in 2nd, which seemed somewhat unlikely as the speedo was showing 119mph and I was about to brake at the end of the Revett straight... Also, halfway through the session the tacho stopped working. It was obviously getting an rpm signal - the shift lights were still working fine. All rather annoying though.

Still, I hadn't crashed. When I started getting the car ready for the race, I was surprised to find that the DASH2 was reporting that the tank was still 60% full. This was just about within the bounds of possibility, however, so I concluded that I wouldn't need to put in any more fuel for the race itself. When the call came, I trundled over to the assembly area, and sat there trying to work out whether the Neuros II was switched on and recording or not. Having the Neuros in its plastic box in the passenger compartment has one major problem - you can't see the indicator light to tell you whether it's recording or not. There's a second problem - the Neuros has two lights - one green and one red. The green one tells you that it's connected to power, but is on regardless of whether or not it's switched on or not. The red one shows you its recording. But there's nothing to tell you if it's on or off. Durrrr... Tim has a way of dealing with this which is to use the Neuros' auto-record feature and put a switch in the power supply to the camera. I have another plan, which is of course far more complicated, but just this once I'm not simply going to do what Tim does. 'cos that worked so well with the power supply for the first Neuros recorder. RIP.

After a considerable amount of faffing with the Neuros, it occurred to me that it was worth warming the engine up a bit, given that the trundle over to the assembly area wouldn't have done so. So, engine started, time to watch the numbers on the DASH2. Water temperature, check. Oil temperature, check. Oil pressure, check. Rear brake line pressure, -3625 bar. Hmm, never mind. Fuel level, 9%. Eh? It turned out, following some brief experimenting, that with the engine off the DASH2 claimed I had 60% fuel. With the engine running this went down to 25%. And then fell rapidly to 9%, at which point the alarm started going off. By this stage there was absolutely no question of heading back to the Scooby and topping up the tank, so I headed out onto the track hoping that I had enough fuel to finish the race and resolving to pull in or pull off if it started spluttering.

The good news is that this time I didn't light up the rear wheels on the grid. I did a test start while approaching the grid, and got very very sideways in the process. This may have affected my approach to the start which, not to put to fine a point on it, I bu66ered up and stalled the car. Happily, since I was at the back of the grid, all two of the cars behind me managed to take avoiding action, and once again I was left to scurry towards the first corner with the rest of the pack miles ahead of me. And just as I hit the brakes for Riches, I noticed the gentle pitter-patter of raindrops on my visor. Oh goody. Racing in the rain. Just look at how well that went last time...

Still, I got round Riches fine, only to discover a scene of moderate carnage at Sear. There were about 6 cars either stationary or moving very slowly, all pointing in different directions. I picked my way rather tentatively through the melee and then made a somewhat leisurely passage down the Revett straight. Before the end I got passed by Austen and Colin who were coming through no matter what - it appears the second corner chaos was largely attributable to Austen nerfing Colin on the exit from Sear. I wasn't feeling in the mood for a braking battle into the Esses so I decided that discretion was the better part of valour and kept well out of the way. After that I plodded round for a few laps getting used to the conditions. It was very strange - Riches and Sear were wet, albeit variably, and had no grip at all. The rest of the circuit was fine, but you'd occasionally get showers in places which had been dry before with essentially no warning. All very odd.  


Anyway, I gradually got used to the conditions and started to make my way back up the order. Some drivers were very generous and made it easy by being off the track at the time. I did overtake Judi and Ben (one of our newbies and a jolly nice chap too) although I'm not sure about anyone else. After 5 laps I came up behind Bob Mortimer, who'd put in a very respectable qualifying performance with a mid 1:19 lap if I remember correctly. Bob's Fury is blessed with a 'busa engine and it's mighty fast down the straights. Ordinarily I'd probably have settled for following him round as I wasn't convincingly quicker than him at any point round the circuit and the weather was hardly improving. However, I really didn't want to stay behind Bob as his rear right wheel was at a decidedly jaunty angle - about 20 degrees negative camber, I'd estimate. Driving behind him wondering at what point I was going to receive a face full of Compomotive CXR with a garnish of Yokohama AO48R was slightly alarming. When I first noticed it, I was sure I'd be able to get past no problem - after all, a problem like that (which turned out to be a suspension bracket which had broken off the chassis) must slow him down, surely? Unfortunately, Snett has only two right hand corners. One is the first part of the Esses, and I'm frankly not brave enough yet to try an out-braking overtaking maneouvre there yet. The second is the exit of Russell, which isn't an overtaking spot even under the broadest possible definition of that term.

Mind you, the FuryRacer's still cocking its inside front wheel at Russell, as shown in the photo on the left, in a rather endearing manner.

So, putting to the back of my mind the weather conditions and the possibility of running out of fuel, I started to think about whether, if I got a decent run out of Riches, and got a good line through Sear, I might be able to outdrag Bob on the Revett straight, notwithstanding the grunt of the mighty Busa. Sadly, I never got to find out, as going round Riches on lap 7, the back end suddenly snapped out. It was way too fast for me to catch it, and I ended up sailing backwards over the grass on the infield. Happily, this time there wasn't a tyre wall in the way. When I finally came to a rest the engine wouldn't restart. And, indeed, it still won't - if you press the starter button the starter relay clicks but the voltage doesn't drop and the starter motor doesn't spin. The current working theory is that while travelling backwards over the grass I failed to keep the clutch down, with the result that the gear train in the starter system tried spinning the starter motor round very fast backwards, and failed. Whether that's the reason for the engine going on strike remains to be seen - either way, that engine's coming out and a new engine's going in.

So, not a great start to the season - can't drive, qualified at the back of the grid, appalling start, didn't finish. It's just like the old days, in fact. In an attempt to turn things round, I've booked a whole day's testing at Brands Hatch before the next race. Happily, the next race for me is quite some time away, as the next race for everyone else is at Mallory and I'm not doing that round for the usual reason. So I've got until 23rd April to fit a new engine. I'm hoping I can finish it off a few days beforehand...

Many thanks for DH2 aka Dave Hackett for his photos of the race.

28th March 2010

Post-race analysis

If it just the starter system on the engine that's broken, then this could be sorted by removing the engine and just replacing the bits in the starter system (probably the sprague clutch, some of the intermediate gears and possibly the starter motor) which need to be replaced. The indications at present aren't that it's a catastrophic engine failure - although the back end suddenly locking up would be a convenient excuse as to why I couldn't hold the slide. I've dropped the sump and had a poke around - there's no aluminium gravel which would indicate a total internal destruction, nor is there the hallmark little gold specks of a bearing disintegrating. Indeed. it all looks fine in there and the oil is still a healthy gold colour. Pity I'm having to bin 5 litres of fresh synthetic oil which has done all of about 100 miles. Ah well.  

The datalogs support this theory, as I reckon they show that I did indeed lift the clutch (for reasons unknown) while still travelling backwards. By way of explanation, the green line is speed, according to the DL1's GPS data, the orange line is rear wheel speed (rear left wheel in fact), the black line is front wheel speed (again, front left), the red line is throttle and the blue line is steering. The dotted line shows where the 'straight ahead' position is on the steering.

The plot starts on the approach to Riches. The dip in the speed and the lift on the throttle is a gear-change (probably unnecessary looking at the traces), and then the speed tails off under braking. You can see the steering trace drop below the dotted line - that's the turn-in into the corner, and just afterwards the throttle line picks up as I get back on the throttle.

The reason for the spin is apparent from the little orange spike appearing just after 771 seconds - the rear wheels start travelling faster than the fronts, so the back end's lost traction. You can also spot my response - off the throttle and lots of opposite lock. Sadly, however, not enough...

Just after this, after 772 seconds, the yellow and black lines go straight down while the green line drops more smoothly - this was when I was travelling sideways and then backwards with the wheels locked up on the brakes. You can then see when I come off the brakes - or at least brake rather less - the black line (front wheel speed) goes up again and once again matches GPS speed. Notably, however, the yellow line (rear wheel speed) doesn't. I think this is because when I came off the brakes, I let the clutch in as well.


What the logs don't explain is why the gear indicator on the DASH2 isn't working properly. The red trace is the difference between the speed of the car calculated from the wheel speed sensors (used to determine the speed of the car for the gear indicator) and the GPS speed. Although there are a few blips, it's pretty consistent. The yellow and black traces are speed divided by revs - the yellow is the GPS speed divided by revs, the black is wheelspeed divided by revs. On each there are clear plateaus according to the gear I'm in at the time. The DASH2 works (in theory) on the basis that if the speed/revs is within certain boundaries then you're in a particular gear. Given this data, I can't see any reason why it shouldn't be working. I'll try re-loading the calibration file and see if that makes any improvement.