Monthly Archives: September 2009

Knuckling down again

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After some thought I decided whichever method I used to fix the broken clutch slave mount the engine needed to come out. Having spoken to Andy about the Q-Bond he showed me in his unit it’s clear that getting it welded is the repair of choice. On Tuesday evening I drained the sump tank and disconnected the oil hoses, drained the coolant, disconnected all the electrics and removed the exhaust manifold. This meant that all I needed to do then was undo 4 bolts and hoist the engine out. Sounds easy, eh. One fly in the ointment is that the exhaust manifold is cracked again, this time I think in a slight different place to where Clive welded it. No doubt he can sort it again when I go over with the engine.

On Wednesday I collected the prop from BAR – they’ve put a new UJ on the front but said they’d also replaced the one in the middle and the one at the rear – apparently the middle one was showing signs of having stretched so they thought it best to replace them all. It was all rebalanced and repainted, I also got 2 CV joint kits with new boots and bolts. The prop repair was £96 + VAT which I thought pretty reasonable, then it was £70 for the CV joints. Since taking it there I’ve rediscussed the TRT situation with Andy B and brother Andy and I had a chat again with Andrew at BAR. I suspect once the season’s over I might well take the prop back since a TRT may well just prolong the life of the gearbox and diff. An alternative Andrew showed me was a replacement slider spline with nylon coated teeth which is another way of reducing shock loading, but he reckoned a TRT would be more effective.

Wednesday evening I hitched up the engine hoist, undid my 4 bolts and lifted the engine out. And yes, it was a doddle, took about 10 minutes once I’d got the hoist out :) Once the engine was on the floor I took the clutch cover off to inspect the plates. I’ve ordered some Barnett heavy duty springs for it – I seem to remember the ones I put in there were some generic ones, I also wanted to inspect the plates and was very tempted to replace those while the engine was out. Trouble is while a set of EBC plates is £75 the genuine Suzuki ones (reckoned to be better) are £135. Anyway after getting them out and looking in the manual they all looked pristine. The standard spec is 3.0mm +/- .08mm with the limit 2.62 and all 8 of mine were between 2.96 and 3.02mm so pretty much as new :) The springs are interesting, I remember when I put them in that although they look considerably beefier than the originals they were a tad shorter. Measuring them tonight they’re all just over 24mm when the manual says they should be 27.6mm minimum, i.e. they’re a bit short which wouldn’t help on the slippage front. Hopefully the Barnett ones will be a bit longer. The original ones are all about 28mm.

So, once I get the crankcase and exhaust welded she’s ready to go back together again. I’ve spoken to Austen and my old 3.14 diff will be ready at the end of the week so he’s bringing that to Mallory for me. I had been contemplating missing out on Mallory but Bates said I’m not allowed to :D and to be honest even though I’ve had loads of problems this season I haven’t actually completely missed a weekend yet so it would be a pity to miss the last proper RGB meeting of the year.

Assessing the damage

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I was away in Croydon until Thursday night so didn’t get a chance to make a start on the car till Friday afternoon. Andy Bates had recommended that I measure the prop and order a new one from Bailey Morris with a TRT tube, heavy duty UJs and balanced. Trouble is he reckoned that would come in at about £350. I’ve never doubted Andy’s wisdom, and the longer I know him the more my respect for his opinions grows, but £350 is £350 and it’s been an expensive season. I got the prop off and took it over to Andrew at BAR and decided to see what he said. I asked him about a TRT (the idea is that it reduces some of the shock going through the prop) but he made a face and said he’s stopped using them. He asked about my power output and said that GKN have switched their production of them to a different supplier and that since then he’s had a few fail. Basically the TRT is a tube within a tube with the inner bonded to the outer via rubber, he reckoned my 180bhp was likely to shear this. He reasserted that the UJ that’s failed was of low quality and fairly lightweight and said he really didn’t think the other UJs in the prop (one of which he’s already replaced after Anglesey last year) were ever likely to fail in my application and reckoned just replacing the broken UJ and rebalancing the prop would be OK.

I also asked him about the CV joints to find that he knew immediately which ones they were and just picked a box of them off the shelf! When I asked what they were off he was a bit cagey but eventually owned up to them being for a Volkswagen! The prop will be ready for Wednesday.

Back in the garage I got the car up on stands and started dismantling a bit more. I took the clutch slave off to find there was a bit more damage than I’d initially noticed – there’s a sort of post off the crankcase that takes one of the 3 mounting bolts and that had split, so I’ll need to fix that either with some chemical metal or getting it welded. The latter is the best bet but means getting the engine out :( Having said that with the prop, clutch slave and oil pump off I’m about half way there anyway and refitting the oil pump and clutch slave would be much easier with the engine out.

The dry sump pump seems fine – it’s a sturdy billet lump and apart from a scar on the side of it and the ripped out threads where the output spigot is mounted seems unscathed. There doesn’t seem to be any damage to the rigid pipes from pump to sump or to the sump pan where the the pipes are bolted on. That was all good news – replacing either the sump pan or pump would be expensive.

The gearshift lever was pretty bent and when getting it off the spindle the lever broke off the hub. A closer inspection revealed that it had come apart at the original weld. The cable etc. seems fine so I just need to weld the lever back onto its hub which is a pretty minor job.

So, all in all not too bad. It’ s a pity about the clutch slave mount but it could have been much worse. Tomorrow I’ll clean the area up from underneath and take the inspection light under there to make sure I haven’t missed anything. So long as there are no surprises I should be able to get her back together next weekend. At some stage I’ll need to decide whether to venture to Mallory (2 weeks away) or not …

A depressing weekend at Snetterton

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I set off at just after 6am Saturday morning, heading over to Andy Bates at AB Performance. Andy was confident he had a lobro/CV joint that would fit. I avoided the M4/M25 route and went via the Midlands and after an uneventful journey got there just before 11.

We fairly rapidly established that the splines on the inboard end of my drive shaft weren’t standard Sierra. Andy had a few lobros that were the right size but wrong splines. Andy didn’t seem fazed and was adamant we’d sort it. As our series sponsor he’s pretty much worth his weight in gold. After loads of fiddling round trying different things we took Andy’s lobro to bits and rebuilt mine using the cage from Andy’s and the inner/outer parts and ball bearings from mine and it seemed to work OK. So I got the car back together.

Andy also had a few diffs lying around so I ‘borrowed’ the viscous LSD unit from one of them – I had a half-formed plan involving a partial rebuild of the 3.38 diff followed by a diff swap between qualifying and racing. Tim and Derek had both been doing over 130mph at the end of the Revett straight last time here so the 3.62 diff giving a vMax of 120mph was going to be woefully short, even the 3.38 would only give me 129mph. I’d spoken to Austen yesterday and his Dad is going to rebuild my 3.14 diff, the crown wheel and pinion are intact, it just needs rebuilding with new bearings and seals. Apparently the crush spacer had disintegrated causing the input shaft bearing to fail.

I left Andy’s at 3pm and got to Snetterton at 4. Tony Gaunt was there and I collected the 3.38 diff off him and got on with prepping it by tapping and helicoiling the mounts for M12 bolts. The rest of the gang arrived in dribs and drabs and I was reminded why I go to all this trouble – it’s a great atmosphere in the race paddock, they’re a great bunch of people and there’s a great sense of anticipation for the following day’s racing. Tim had helpfully booked the restaurant just by the circuit so a crowd of us walked there for a meal, the food wasn’t bad at all and I had a good chat with Brian and Ian Baldwin, creators of Derek’s BDN S3. Some people like being big fish in small ponds but I’m quite happy in the company of people who know vastly more than I do, it’s part of the attraction of RGB really.

So I started the day full of anticipation. It was an early start with scrutineering at 8am which was uneventful. After a bit of preparation we headed to the assembly area at 8.45 for the Bikesports qualy session. I had new front brake pads that I wanted to try to bed in as well as getting to grips with the new gearing. The brakes seemed fine, the car was noticeably shorter geared but all seemed fine. I didn’t really get any quick laps in, Andy and Rob Grant’s mechanic Mark was out in what used to be Colin Duce’s Fury and was having a bit of a torrid time with a clutch that didn’t want to work (probably because the engine had been standing for a long time) and first of all he parked up on the racing line on the exit of the Bomb Hole with white flags being shown then a bit later just before the Russell Chicane resulting in a red flag. After the restart I got a couple of quicker laps in getting down more or less to my fastest lap from March. I wasn’t too unhappy as I knew I could go much faster. I was hitting the limiter just before the 300m board before the Esses with the braking point being around the 100m mark so I wasn’t losing too much time there. My main problem in the session was awful clutch slip meaning I could never get on the power hard out of any of the corners. It seemed worse that it had ever been before :( I managed a 1:23.63 in the end, 0.3 seconds slower than March.

After the session I decided to run the RGB qualy session with the car as it was and leave the diff change till after it giving me around 3 hours for the swap. Andy Bates had fitted the LSD unit into the 3.38 diff and had the diff ready to swap my drive flanges into it. Brian Baldwin came over and we were talking about my clutch slip. We agreed it seemed unlikely to be anything to do with the actuating mechanism and he asked what oil I was using. Since the winter I’ve been using Silkolene Race 15w50 which seemed to give slightly improved oil pressure when it was hot. Brian reckoned that was the cause of the clutch slip – they’d tried it in Derek’s car a couple of years ago and gave up on it straight away because of clutch slip. Andy Bates came over and at the first mention of Silkolene agreed that was the likely cause, he’d also stopped using it some years ago. So I grabbed 8 litres of the Maxima 15w50 that he supplies. I’m aware that Andy supplies Maxima and is therefore biased, but the reason he supplies it is that he back to back tested it against the Castrol he used to use and got a bit more power but more importantly better oil pressure. Changing the oil actually took quite a long time by the time I’d drained the engine, the dry sump tank and taken the filter off to get the oil out of there and I was still grubbing round under the car when they called us to the assembly area so it was a bit of a rush getting changed and getting over there.

This session was much better – of course my clutch plates were still soaked in the Silkolene but there was an immediate difference and it got better with a couple of laps. I was quickly seeing low 1:23′s and the diff ratio was becoming a much bigger problem, I was now hitting the limiter by the marshals post halfway down the straight and hitting it consistently on the much shorter Senna Straight. I did see a 1:22 on the lap timer so knew I was going faster but the diff must have been losing me an additional second or so as I was sitting at 118mph for a good 600m or so when I should have been hard on the gas.

As I came round towards the finish for the chequered flag I was aware of some vibration that felt drivetrain related. I suspected the rebuilt lobro so took a very slow in lap. I tried wobbling the driveshaft about and indeed there was a bit of play so I thought the lobro was on its way out, but Andy Bates noticed the diff drive flange was moving and thought it more likely the diff was causing the problem. So I got changed and set to getting the diff out which meant draining and removing the fuel tank, all the tunnel panels etc. It took just over an hour to get it out then I took it over to Batesey’s truck and he removed the drive flanges and stuck them in the other diff, we stuck some new oil in and replaced the cover.

Getting the diff back in is a bit of a pain but it was all going OK and I was on track to have it done in time till they announced over the tannoy that our race was brought forward from 2.30 to 1.45! By now it was just gone 1pm and I was sticking the diff bolts in. Andy Cunningham came over and gave me a hand as we refitted the prop, tunnel panels, drive shaft bolts, fuel tank etc. Time was really running out so more hands arrived – Brian Baldwin, Paul Rogers and his mate Andy all mucked in. Derek helpfully pointed out that even if I missed the race start I was allowed out into the race from the pit lane.

I did miss the race start but went round to the assembly area where the marshals held me while they checked on the radio that it was OK to let me out. Meanwhile I reprogrammed the dash for the new diff ratio. As soon as I got out of pit lane I could feel a vibration. This really wasn’t what I wanted! I tried to keep off the racing line as the leaders came round as I was on cold tyres and going slowly. As I went up the Revett straight I was more aware of the vibration which became bad enough to blur my vision slightly so I backed right off at the Esses and decided to pull into the pits. I raised my hand and moved over to the extreme right edge of the track and slowed right down. As I came out of Coram and on the short straight to the chicane something let go and there was a clattering in the tunnel so I pulled straight off onto the grass shut down and hopped out and watched the race with the marshals.

There was a trail of oil from the spot where the big bang had happened and I had a horrible feeling that perhaps the failure this time was the prop but that it had then lunched the front of the diff :(

I suggested to the marshals that because I thought the problem was prop or diff related it was best not to tow me back so they winched the car, with me in it, onto the back of the flatbed recovery truck. I was told to stick my helmet on and keep my foot on the brakes. I was waiting for the driver to tie the car down but realisation dawned that that was why the instructions regarding helmet and brakes – no tie downs! It’s funny but I never really worry about the brakes failing when out on track but while bouncing along going backwards on the back of this flatbed I did!

Back in the paddock we looked under the back of the car and saw no oil, suggesting it wasn’t diff oil. Lifting the bonnet immediately revealed the problem – the front UJ of the prop had failed, the prop had then done the customary flailing about and had broken the spigot off the dry sump scavenge pump resulting in the pump then enthusiastically scavenging the oil out of the sump pan and onto the track :(

There was no obvious damage to the engine casings but to be honest I had pretty much lost the will to live and couldn’t be bothered having a proper look. It could of course have been much more serious but telling yourself that never really helps much. All my tools were still out from the frantic diff swap and there was 7 or 8 litres of Silkolene still sloshing round in my drain tray so I got rid of all the oil, cleaned everything up, tidied the tools away and stuck the Fury back onto the trailer.

I had a chat with Andy and we’d both reached the same conclusion – that the original primary problem was actually unknown but the diff failure at Oulton, the lobro failure at PDQ and this were all related. I suspect the prop might actually have been the primary problem setting up some vibration which then damaged the diff at Oulton. He suggested getting a new prop from Bailey Morris as he’s given up getting them elsewhere due to failures like this. He says he always specs heavy duty UJs and a TRT tube (which gives a bit of cushioning in the system). What I actually plan to do is go back to BAR who fixed it last time (and indeed commented that the prop had originally been made using cheap inferior UJs) and talk to them about what they can do to produce me a bomb proof prop. I’ll also replace the lobros and get a couple of spares (and find out exactly what vehicle they’re originally off to make sourcing replacements easier).

I will of course be back, I’ve gone to far too much trouble to bail out now. Also I feel like my driving’s getting better and the car’s just so good to drive when it actually is working OK with the engine working really well and the handling feeling reasonably balanced. Indeed my fastest lap in the RGB qualy was 1:22.35, a second quicker than in March and I suspect I was losing at least a second from being undergeared. At least I discovered (and solved) the clutch slip problem although a lot of the nice new oil I got from Andy was deposited on the track. Whether I’ll be at Mallory in just under 3 weeks time I’m not sure but I’ll do pretty much whatever it takes to be at Silverstone for the Birkett on October 24th.

Monday lunchtime I took the airbox off and had a better look. I think to say I’ve been lucky would be overstating it but the damage appears minimal.

  • The scavenge pump appears to be unmarked – what appears to have happened is that the prop has hit the spigot and ripped it off by stripping the aluminium threads out of the housing, the 2 screws are still there attached to the spigot and the O ring is even still there. The spigot and hose are badly marked but look to be serviceable.
  • The gear shift lever is a bit bent but looks intact although I’ll need to have a more careful look to make sure the shaft isn’t bent.
  • There’s a bit of damage to the loom where the prop’s hit it but all the wires are intact with just one of them having a bit of bare copper visible.
  • There are no marks anywhere on the engine casings so that appears unscathed.
  • The sump tank is still at 2/3 of the normal volume so firstly there’s no risk the engine suffered oil starvation and secondly I didn’t lose all my new oil!

PDQ

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With the diff sorted I would be able to keep my appointment at PDQ on Friday. It’s a bit of a trek but I’m keen to get the car mapped properly not just to maximise performance but also to make sure it isn’t running lean and risking damage. It’s a bit of a trek to Maidenhead and it would have been nice to do it on the way to Snett but we aren’t racing till Sunday and I don’t fancy sitting round at Snetterton all day Saturday.

On the way to Oulton I’d had a couple of problems with the trailer. Firstly one of the welds on my wheel rack had let go and I’d had to bodge it together with some luggage straps. So on Tuesday evening that got welded with a bit of reinforcement. One of the offside trailer wheels (it’s a twin axle trailer) had also kept locking up under braking resulting in much screeching and clouds of smoke. I jacked it up and had a good look at the tyres but no flat spots. The brakes didn’t seem to be binding but the front wheel on that side seemed to have a little less clearance so I slackened off the brake shoe adjuster a bit. I wonder if perhaps one of the axles is taking most of the weight (due to the towbar height) leaving one wheel very lightly loaded and therefore easy to lock up.

On Wednesday I had a quick chat with Andy Bates who said I’ll need a lambda bung in my manifold for PDQ to map it. I do have one but it’s just welded on without the hole being drilled through the manifold. I’d meant to drill it out while it was off for repairs recently but forgot, so I whipped it off and got that sorted. The clutch slave cylinder also came off for me to clean up the clutch pushrod – unlike on some bikes the outer end of this sits in fresh air and it was indeed quite dirty with a slightly rusted surface. A bit of work with some wet and dry followed by Solvol Autosol soon had it nice and shiny and after giving it a liberal coat of grease I replaced it and refitted the slave cylinder. Hopefully now when I let go of the clutch pedal it’ll spring out nicely and cure the clutch slip when I first apply power coming out of a corner.

Andy also suggested me coming over to his unit before Snetterton and hybridising the diff so I have the correct ratio for Snett. Very tempting but would involve a significant change in plans. It would also involve adding quite a bit of time pressure to the weekend – just getting the diff out and refitting it is several hours work without the work involved in swapping the slipper unit over to the 3.38 diff and swapping the drive flanges etc. So I decided to stick to plan A.

PDQSo Friday morning I left just after 5 and was at PDQ at 8.30. Nick there was very friendly and the place was very professional looking. He got the car strapped down, screwed his lambda sensor into the manifold, connected the PowerCommander to his computer and set up the extractor and fan onto the rad. We got her warmed up and he got in and familiarised himself with the gear change. Once he was ready he took her through the gears and was just starting a power run in 4th gear when something went wrong. He’d lost drive :( We shut her off and I removed the tunnel panels and rear panel to find the right hand lobro connecting the drive shaft to the diff had failed and spat a ball bearing out.

I was really pleased. I rang Andy Bates and talked through the options. He was pretty confident he had the parts in stock to fix it. He did suggest bringing the car over and swapping the diff too but as I don’t yet have the 3.38 that was a non-starter. I decided not to bother trying to source a new lobro there, although Nick was really very helpful and was happy to carry on with something else and do my car again later. I got her back on the trailer and thought through my options on the way home (in addition to wondering what I’d done wrong to deserve all these problems!). They were basically:

  1. Bail out, abandon the weekend and sort her out for Mallory
  2. Try to find a new lobro/CV joint locally at home and fix the car
  3. Just head over earlier than planned on Saturday and go to Andy’s and replace the lobro joint.

I was home late lunchtime and set about trying to find a new CV joint. Lots of places could get me one for Monday, and one place even for late Saturday morning, but it was difficult to be certain it would be the right part. In the end I went for option 3 and decided to head over to AB Performance early in the morning.

Another diff change …

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It’s only just over a year since I modified my chassis to take a Sierra diff. The choice was made on the basis that the Sierra is stronger than a Freelander diff, also that no-one in RGB had had a Sierra diff fail. Until it’s stripped down I don’t know why it’s failed. I suspect one of two reasons, either the bearing set I bought for the rebuild was of poor quality and the bearing has just failed, or the pinion nut has come loose. The crown wheel and pinion set I got was a bit odd in that the pinion nut has a right hand thread, this caused a delay in the diff rebuild last year as they’re usually a left hand thread and I wonder whether this has caused the problem. I spoke to Austen and his dad on Sunday and I’m going to ship the diff up to him to rebuild it.

Austen also suggested speaking to Andy Grant who he thought was breaking his old Fury. I got hold of Andy Sunday evening and he is indeed prepared to sell me his 3.38 ratio LSD. He’ll get Mark to remove it and I’ll get it couriered over later this week. This should be a straight swap and a 3.38 will give me about 129mph which is probably actually a better ratio than 3.14 for most circuits – at Oulton I was only using 6th very occasionally.

I realised Monday morning that there might be one small fly in the ointment, the lower mounts on my diff are helicoiled to allow me to use bolts rather than a long stud right through, and indeed I physically can’t get a stud through as the chassis rail is in the way. 10 minutes on eBay sourced me an M12 x 1.75 helicoiling kit and some set screws – the ones in my diff are actually M12 x 1.5 pitch but the bolts are a pain to find so a standard coarse pitch makes more sense.

The other issue is my slipping clutch. I’ve been thinking about this and have decided I think it might not be clutch plate wear. I first noticed it at Snetterton which was actually only the second race weekend for the engine and the engine was pretty new when it went in so unlikely the clutch has worn. I wonder if the clutch pushrod is just sticking a bit, it’s most noticeable when I first exit a corner (i.e. the first application of power after using the clutch) and happens in low gears, the clutch slips for a second or two then seems to grab OK and it doesn’t happen after subsequent gear changes. Probably worth me taking the slave cylinder off again and taking the pushrod out to give it a good polish.

Andy Bates had recommended that I add some reinforcement to the diff bracketry, he reckoned it may well crack with time. In fact the 2 brackets at the nose of the diff had separated, the offside one being missing, i.e. the bolt had vibrated out too. In fairness these 2 brackets will have had quite a lot of force on them with severe vibration when the diff input shaft went wobbly. So I made up 2 new ones that were a bit more ’3D’ and had over double the length of weld holding them on to the chassis. I got those welded onto the chassis on Thursday evening and added a length of 4mm plate across the 2 lower mounting brackets to brace those too. TNT collected the diff from Andy during the afternoon so I was hopeful I’d have it in time for the weekend.

The diff arrived Friday morning although I wasn’t there as I had a day in London for a meeting. I started early on Saturday morning, with a clean up of the diff. Someone’s clearly marked “3.38″ on it but I thought I’d check by marking the input flange and one of the output flanges and counting the turns. Sadly it ain’t a 3.38 but is a 3.62 :( It does have an LSD though. It’ll be far from ideal, especially at Snetterton with the long back straight but at least it’ll get me out there. I got the oil and general crud off it with some Gunk followed by oven cleaner and a bit of wire brushing. I then drilled the right side flange for my speedo magnets.

I’d ordered some new brake pads from HiSpec before Oulton but they didn’t arrive till this week. They needed a bit of filing/sanding down to fit without binding but they didn’t take long to fit.

I couldn’t get the drain plug out of the new diff so I removed the rear cover, spent ages mopping up the poxy oil off the floor then stuck a litre of fresh oil in and replaced the cover. The mountings were already tapped for 12mm bolts so i didn’t need to bother with that, so I then juggled the diff into the chassis and got it bolted into place.

One of the CV joints then decided to fall apart dropping ball bearings on the floor and proved impossible to stick back together in the confined space I had. So I removed the brake caliper and took the hub off the upright so I could get at it better. I eventually got it sorted, then needed to regrease it and bolt the drive shafts back onto the diff. On Sunday morning I got the prop bolted on, followed by the reverse mechanism then replacing the fuel tank. After that a series of smaller jobs – redoing a couple of the rivnuts to hold the tunnel panels, replacing the tunnel panels, cleaning the residue from the diff oil from inside the car etc.

At Silverstone I’d failed the noise test, so I took the silencer off and had a look at the packing. There was one layer around the perimeter of the can, the rest was all melted into chunks of glass or gone completely. No wonder it was at 107dB! This time I wrapped the perforated tube with some stainless wool secured that with some stainless wire then repacked it. I also trimmed the sidepod where the exhaust had been hitting it and burning it.

Once that was all done it was time for a tidy up then into the house in time to watch the Italian Grand Prix at Monza. It’s a bit of an anniversary for me this weekend – it was watching the Monza practice last year that I realised my retina had detached, and I was watching the race in the ward on the Sunday when they took me off to the operating theatre. Looking forward to watching the whole race today :)

Oulton Park

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Yet another week of frantic preparation completed just in time. It’s all quite stressful, but once everything’s packed and I’m on my way I can relax and look forward to the weekend, although it’s getting to the stage that I’m regarding problems as being inevitable. I got to Oulton Park before 8pm, got the car off the trailer and the tarp over it, had some food and settled down for the night. Just like last year I woke a couple of times in the night to the sound of rain hammering on the roof. I got up early and the weather looked OK so I went for a jog round the circuit which was very pleasant as well as useful, nice to eyeball all the corners and especially the kerbs to see which ones are OK to use and which ones are likely to either break your suspension or launch you into the scenery. It’s a lovely circuit, quite fast with a good mix of corners and some big gradient changes. Not much run off though! Lap time was 24:57 :D

The car was pretty much ready – prior to loading it I’d quickly checked the rear wheels to find the offside wheel had positive camber. I presumed the upright had undergone some form of adjustment when that wheel went into the gravel at Silverstone. A careful inspection revealed no cracks and no visible deformation anywhere on the upright or indeed in the suspension. It seems every time I have some sort of incident in the Fury the suspension goes out of alignment without me being able to find anything bent/broken. I soon got it cambered the correct way and went through the rest of my usual checklist. I hadn’t found anyone I knew the night before but Andy and Rob Grant were there with Mark their mechanic, Andy was driving his Radical in the All Comers races. Tim Gray was there in a borrowed Radical and during the morning Paul Rickers and Doug Carter pitched up so we sort of had a little RGB corner.

Scrutineering was fine. The noise was recorded at 107dB going into the assembly area for qualy which was a bit puzzling. Maybe the exhaust just needed packing, but it seemed a few others were recorded at higher lvels than they’re used to. I said I’d repack it and carried on. There was a great mix of cars out, quite a few Radicals, a Locost, a few MR2s and Golfs and a Phoenix. The car seemed fine apart from the speedo not working meaning no gear indication, a minor irritation but surprisingly off-putting. I was also getting some clutch slip again, occasionally I know I’m resting my foot on the pedal but it’s also definitely happening with my foot well away. My plan was to enjoy myself and not crash. I got past a couple of the slower cars and came up behind the Phoenix, he seemed fairly quick but I was a bit quicker in a few places. I had one look up the inside at the left handed Island bend but it’s a fast 5th gear corner and I bottled out and dropped behind him. I eventually out-dragged him down the finish straight. The car was pulling really well again, I kept hitting the limiter which didn’t used to happen as it used to run out of puff before then and I’d shift up. My fastest lap here last year when I was trying quite hard was 2:01.11 so I was really pleased to see 1:59.2 on my dash, although the official timing said 1:59.57 with my second fastest lap 1:59.73. That put me 10th on the grid of 26, with 8 Radicals and Doug Carter in front of me. 9th on the grid was 4 seconds faster than me and the Phoenix I’d diced with in qualy was half a second slower followed by a Clio, a Seat Leon and Paul Rickers.

At Silverstone I’d been aware of really bad understeer. I think it’s partly a feature of the circuit somehow but following a helpful email discussion with Tim I softened off the front dampers a bit and wound the spring platforms at the rear up a turn each side. I don’t know whether it was the changes or just a different circuit but she felt much better balanced with no sign of understeer and what oversteer there was I could manage OK.

After qualy there really wasn’t anything major to do to the car. It got some fuel and a bit of a clean and the routine checks. By the time of the first race it was a nice sunny day with a completely dry track. Again I reminded myself not to get caught up dicing, especially the first few corners. We had more or less a full lap of the circuit to get round to the grid and there was more noise from the rear end of the car on the over-run and a bit more backlash than usual. This got a bit worse on the green flag lap and I wondered about going in but in the end decided not to. We reformed on the grid, the lights went out and I got another great start, shot past Doug in the row in front of me but I then got out of the throttle as I had wall to wall Radicals in front of me and I tucked in behind Doug going into Old Hall Bend. Going down the Avenue a yellow Radical ran wide onto the grass so I gave him a wide berth in case he spun as he rejoined, I had the Seat Leon snapping at my heels – he was on slicks and presumably was quite a good driver. Doug and the Radicals scarpered, I soon gapped the Leon (I think he ended up in the gravel by Cascades after a couple of laps) and after a couple of laps couldn’t see him or indeed anyone else in my mirrors. With no-one to race I took it steady trying to nurse the car as she was making some horrendous whining noises going into each corner.

On the cool down lap I was even more aware of the problem and as I pulled into the paddock the car stopped rolling quite abruptly and I could smell gear oil. I hopped out and there was diff oil at the back of the passenger area and under my seat :(

I took a few panels off and discovered that the diff input shaft was wobbling around quite horribly. I’d wondered if either my prop bolts had come loose or the diff mountings had let go but it seemed to be a simple mechanical failure of the diff input shaft bearing. So, not my fault and another of those things you just don’t expect to happen – when I changed the diff last year I took loads of advice and the consensus was that a Sierra diff was the diff of choice due to its strength …

So that was the end of my weekend. Back home on Sunday I got the diff out and took the back cover off to have a look. It seems the pinion shaft has slid backwards so the rear face of the pinion has been rubbing on the housing around the main bevel gears. The helical mating surfaces of the crown wheel and pinion looked OK, I’ll be mighty pleased if it can be rebuilt, the 3.14 crown wheel and pinion cost me a fortune. It’s 2 weeks to Snetterton and I’m booked into PDQ for a mapping session in 12 days. Realistically I need to find another diff to stick in there, it’s likely the only immediate option with an LSD will be a 3.62 which will top out at 120mph but that’ll be better than not getting out at all. It’s a PITA having to swap the diff but a straightforward mechanical job and a nice change from all that damned fibreglassing! Sunday evening I spoke to Andy Grant who is prepared to let me have the 3.38 diff from his Fury so I could be in business.

On the plus side, I didn’t crash! I do think my driving’s improving a bit but it’s clear the engine has been under-performing all along. The DigiDash gives an estimated power/torque output using the speed and the known weight of the car. The absolute figures are a vague guestimate but so long as the speedo readings are accurate they at least give a reasonable comparison. Here’s the plot from the race at Mallory, this gives maximum rear wheel power as about 113bhp with the peak at 7900rpm.

Mallory09Power

And here’s the all new, fully airboxed-up, full fat version from Oulton, maximum power up a whopping 40bhp at 145 with the peak shifted up by over a thousand rpm at 8940rpm! The torque’s up by about 12 ibft from 81 to 93 but more importantly it’s a much fatter, flatter curve. It’ll be interesting to see what it looks like after we’ve been to PDQ!

Oulton09Power

Here’s some video, qualifying first then the first 2 laps of the race, I’ve stopped it there cos nothing much happened after that, no-one in sight in front or behind!

Oulton Park Preparations

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I dropped the exhaust off with Clive in Ammanford on Tuesday and asked him to stick a bracket on the back end of the manifold as well so the system isn’t as stressed. He suggested he weld the whole lot back together then add the bracket when I came to pick it up so I could decide where I wanted it.

Tuesday evening I got going on fabricating a replacement bonnet hinge. I expected this would take ages but was pleasantly surprised – after cutting the tubes to length it didn’t take long to weld them together then sort out the fixing holes etc. I got up early on Wednesday and got it painted. I also made a slight modification to the airbox, stiffening up the aluminium strip that holds the air filter in place. I then put in a bit of elbow grease cleaning up the rear tub – on Monday I trimmed back the wheel arches as they were sticking out too far and touched up the worst of the paint. Some white spirit to get all the oil/rubber marks off then some AutoGlym Resin Polish and the whole thing’s looking much better :)

I got the exhaust back at lunchtime and can’t believe how neat a job Clive’s done. He got the bracket welded on too so all I need to do is make a hanger from the chassis and the whole lot will be much more secure. I’m running out of time but I’m down to fairly straightforward refitting jobs now, with Friday off work I should have enough time to get her sorted for Oulton. I’m really keen to get there – apart from just wanting to get out in the car again Oulton’s a really nice circuit and one I have fond memories of as a 17 year old going there on my bike on the Easter weekend to watch Barry Sheene, Kenny Roberts, Randy Mamola, Ron Haslam et al. in the Transatlantic Trophy.

Thursday evening I finished off fixing the bonnet brackets that were a bit bashed up, then fabricated a bracket to hang the rear end of the manifold off and welded that onto the chassis rail. I also ran the engine up to temp to check the cooling system was working OK which it was, with the fan switching on and dropping the coolant temp nicely. I’d rung the 750MC office at lunchtime and entered Saturday’s races so I was now committed :)

Friday morning saw an early start in the garage. I painted the bonnet brackets then got going on the front suspension geometry. Something had obviously bent somewhere in the crash as the left front wheel had more camber than before. So I took both wishbones off and carefully checked over the wishbones, rose joints and all the suspension mounts for damage. I couldn’t find anything – all the mounts were re-fabricated by Andy Bates after the Snetterton crash and in addition to using some thicker plate for some of the bits all the mounts are gusseted and braced far more than as standard. All the welds are pristine, paint all intact and everything looks straight. After cleaning it all up I got it back together and set everything up, I’ve given it a little more camber than before at about 1.75° and set the toe-in to 2.5mm again. By 8.30 it was all exactly as I wanted it.

Refitting the bonnet took quite a while, then I had to work out what to do with the air duct. I ended up using a length of the neoprene hose I got from Merlin which just butts up against the inner end of the NACA duct held in place by an aluminium bracket. It ain’t pretty but it should work for now. I had to cut another circle of white Fablon and stick that on the bonnet followed by the numbers, then stick the rear body back on and she was ready to go.

Once that was done it was lunchtime – time to tidy up, sort out the tools, load everything up and get on my way oop north.

Post-Silverstone Repairs

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The next RGB race is in 4 weeks time at Snetterton on 20th September. I was planning to miss this round as it’s a single 13 minute race and Snett’s 300 miles from here. I was thinking of doing the Bikesports race at Oulton on 5th September as it’s nearer and a much nicer circuit. In the aftermath of this latest crash I thought it best to take pressure off myself by abandoning the plans for Oulton as it’s only 2 weeks away and sticking with the plan to miss Snett.

Trouble is I’ve had a taste of mixing it with a some of the slightly faster boys now and really want to get back out there. Jen also was fairly encouraging and suggested I go for it. I still think Oulton is a bit ambitious, but I think I will plan for Snetterton.

Apart from fixing the crash damage the other job I really want to get done now is getting the Power Commander mapped properly. The place to get it done is PDQ near Maidenhead, recommended by both Andy Bates and Darcy Smith. I gave them a ring on the Monday after Silverstone to get booked in, the first date I can get in there is 18th September, the Friday before Snetterton.

SilverstoneCrash01On the Tuesday morning I went out and removed the bonnet to inspect a bit more carefully. The steering rack seems fine with smooth movement lock to lock, the left steering rod is a bit bent but I think I should be able to straighten it. I was thinking of getting another rack as a spare anyway. The wheel although having a gouge on the rim is running true with no wobbles. The oil cooler braided hoses have taken another fairly severe beating and I think the time’s come to replace those. The rad fan was hanging off but seems intact, I think the plastic pins used to secure it have broken but I have a spare set. The oil cooler is definitely knackered now. The new airbox took a bit of a bash when the bonnet got slewed round but will be OK. SilverstoneCrash02I also had a better look at the bonnet and apart from the front left quarter of it having been completely wiped off the rest of it’s in pretty good shape. I think I can chop the front left quarter off the old one and graft them together.

So I did some online ordering and some telephoning and ordered a new oil cooler and 4″ duct from Merlin, some more braided hose and a steering rack from Rally Design,, some replacement bonnet latches catchplates from Protex. I got some steel tubing from B&Q to make a new bonnet hinge and a length of aluminium angle to make a couple of brackets to support the airbox rather than just relying on the rubbers to hold it on (it popped off in the impact).

In the evening I made a start at some dismantling – I took off the oil cooler and radiator so I could straighten the rad brackets. I wanted to take the steering rod off the end of the rack to have a go at straightening it but couldn’t get it to budge – it looks like it just unscrews but I decided to take the rack off to have a proper look. Trouble is then I couldn’t undo the track rod ends – the one on the nearside was just spinning and I couldn’t get the nut off, the off side one I got the nut off fine but couldn’t budge it out of the taper despite using the big hammer. I gave it a spray with WD40 and decided to come back the next day with a splitter.

Wednesday evening the rod ends soon gave up their futile resistance. With the steering rack on the bench I could see there was a small staked tab preventing me from unscrewing the rod end from the rack. Once it was off a bit of heat and a moderately severe beating with the hammer and I had the rod end looking straight again. I could also inspect the rack itself to confirm that it wasn’t injured. A clean up and some fresh grease and the rack was soon back together again.

After working all day Thursday then working overnight I decided sleep was for wimps and was on a mission. Shopping first to pick up some new track rod ends from the local motor factor – the old ones are OK but I’ve decided to start increasing my stock of spares. Then off to Livermores for more 2 pack primer, paint and hardener. Followed by a tidying up session in the garage – I can see my bench now :-)

SilverstoneCrash03I made a start next on the bonnet, figuring that would be my rate-limiting step. I cut away the damaged section of the bonnet and marked up the old bonnet to cut a matching section off it. It took quite a time trimming the section to fit but eventually I riveted the 2 pieces together using strips of aluminium. I then got on with applying GRP to the inside of the joint. The section I’m using is already fairly badly damaged itself and the bit slot where the tow eye was didn’t help much so I also patched that up a bit as well. It’s going to need quite a bit of tidying up with more resin/mat and filler etc. but at least it looks like a bonnet again!

The braided hose and steering rack arrived from Rally Design. I’d also ordered another radiator – although the one I got was the correct width and height it was slimmer at 20mm compared to the previous one’s 34mm. I figured this accounted for the slightly higher temps I was seeing at Silverstone. After a bit of searching I found an even cheaper source of radiators – Norther Radiators’ price was £21 + VAT, even with carriage the total was only £36. That arrived Friday and looked perfect, I’ll keep the other as a spare.

SilverstoneCrash04On Saturday I drilled out all the rivets and got the bits of aluminium off the bonnet. I added some reinforcement to the dodgy bits, glassed a new bit to bolt the mount onto then turned it over and filled the holes and joints with some gelcoat. Here it is in all its glory. Yes, I know it looks crap but I reckon I can improve it.

In between waiting for bits of GRP to harden I continued with the mechanical bits, getting the steering rack lined up right on the column then refitting the fan to the rad and fitting the rad and oil cooler back onto the chassis. I also removed the airbox so I could refit the throttle bodies onto the cylinder head. Getting the main oil hose off was a pain and required removal of the clutch slave cylinder. Once it was off it took a while getting the fitting off – the ProGold fittings from Rally Design are completely reusable, even the olive. I figured I could chop the long hose down, removing the damaged part and use it as a replacement for the shorter length from the oil cooler to the tank.

SilverstoneCrash05Sunday saw little progress, golf and work got in the way. I did however get the oil hoses made up and fitted and made a start on sanding the bonnet followed by applying some filler. Monday morning I set to it with the angle grinder and flap wheel – if you’re very careful you can get a reasonable finish with this and it really makes quick work of it. By lunchtime it was ready for a coat of primer (see pic, see, I said I could get it looking better ;) ) – I’m using a high build primer and didn’t bother with any thinners so I could lay it on pretty thick without any runs or sags.

SilverstoneCrash07Once the primer had hardened I removed a strip of masking tape (I’d masked off a lot of the bonnet) and cut back the edge of the primer with some coarse wet and dry. The top coat went on mid-afternoon and she was looking a bit like a bonnet again!

SilverstoneCrash06While I was waiting for the paint to harden I stuck oil and coolant back in as the car’s mechanically back together again now – here’s the front end looking nice again with shiny new radiator, oil cooler, braided hoses and steering rack. The dry sump tank was looking pretty empty – when the cooler broke oil sprayed everywhere – fortunately the oil goes to the cooler en route from engine to tank so it didn’t seem likely she’d been deprived of any oil since the system holds about 9 litres and I shut it off immediately. It took almost 4 litres to refill the tank. I refitted the airbox and fired her up – I’d noticed a crack where the inlet pipe goes into the silencer and it was blowing like mad. I then realised oil was overflowing out of the top of the sump tank so I switched off, mopped it up and diverted the breather into the empty oil container and tried again. I guess the oil had all drained from the sump tank into the engine, certainly the oil pressure was fine.

SilverstoneCrash08I was thinking of welding the silencer myself but when I took it off the end was broken off the manifold. So I took the manifold off too to get that welded only for that to fall into 2 parts as well! The 4-2-1 system was now 2 separate 2-1′s with the collector cracked down the middle. Hopefully Clive who does all my important welding can work his magic on it, I’ll try to take it over to him tomorrow.

Oulton’s only a few days away. I’m very keen to go but will have my work cut out!