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One Man Band - Teardown and Reassembly



The whole thing from start to finish

Packup



  • Loading car into trailer (out of shot)
  • Packing up spares and tools
  • Quick (preliminary) cleanup of workshop

Reassembly Part 3



  • Cleaning pickup off tyres
  • Laying out scales in flat 'patch'
  • Wheel alignment and corner weighting
  • Installing extra element in rear wing
  • Lowering to ground

Reassembly Part 2



  • Exhaust fitment
  • General cleanup and finalisation of connections (oil, hydraulic, electrical)
  • Installation of floor (diffuser)
  • Installation of bodywork

Reassembly Part 1



  • Transmission installation and reassembly
  • Systems reconnection and oil replenishment
  • Installation of exhaust
  • Work completed to recondition the clutch and input shaft has been omitted from the video

Servicing Part 2



  • Disconnection of systems
  • Removal of transmission
  • Removal of clutch

Routine Servicing

We've already had our first round for 2010. The last ever race meeting at Oran Park.

Sam was unlucky to suffer clutch failure while comfortably leading the opening Formula Tasman race. Whilst it was a shame to miss out on completing the final event at Oran Park, we're going to make the most of this misfortune, and we're planning a video series, following the maintenance process on the Reynard 94D, from arrival in the workshop, to reassembly, ready for the next round.

The first video in the series is below. Stripping the car down.



  • Removal of bodywork
  • Removal of floor (diffuser)
  • Removal of wheels
  • Removal of exhaust
  • Disassembly of transmission

iRace Video

A short highlights video from Oran Park

Guns Blazing

Mumbo Racing returned to the circuit on the weekend, for the first time since April, and it was with much success.

The team fielded three cars in house for the inaugural round of the Independent Race Series, with a fourth car run by Mathew Fox.

Friday saw unofficial practice on the flowing Oran Park "South Circuit", and Neil Byers was doing double duty in his Ford Mustang Cobra R V8 Giant, and his Mitsubishi 380 Production Racing Car. Both cars ran strongly during the day, and even managed to give a few passengers a thrill in the passenger rides in the afternoon. Sam Dale arrived late on Friday with his Reynard 94D, but wasted no time getting on the pace. Mathew Fox was driving the Hyundai Lantra Super Tourer in the Touring Car Challenge.

Saturday morning brought official practice, followed shortly thereafter by Qualifying, and then a packed day of racing (the event was a one day meeting).

PRODUCTION RACING CARS
In the Production Racing Cars, Neil Byers took a little while to hit his stride, but once he did he was on fire. In Saturday morning's official practice session Byers clocked a 52.41s lap, good enough for 5th fastest.

In Qualifying Byers went a fraction slower, with a 52.65s lap, and paid the price, dropping one place to take 6th on the grid.

It was in the first race that Byers really upped the ante. He got an excellent start, and moved up to third by the end of the opening lap, from there he was never challenged, and held onto take out third place in the race.

In the reverse grid Race Two, Byers was again on fire, his start wasn't as hot as the first race, but he clawed his way up to third by mid-race, and then spent the rest of the race threatening Bryan Fitzpatrick (Renault Clio). Fitzpatrick ultimately held onto the spot, and Byers took another third place.

In the third race, Neil really opened the taps. He followed up a reasonable start with some blistering early laps, to put himself in touch with the leaders. Byers didn't hesitate once he got near the front, and passed Anthony Soole (Toyota Celica) to take the lead. From there, despite a strong challenge from Soole, Neil was never headed and took his first race win in his time with the Mumbo Racing team. This race was Neil's strongest performance of the weekend so far, and he managed to break into the 51s laptime bracket.

In the final race Byers was headed by Soole in the early laps, but he slipped through, and held the lead until the end, giving him his second race win, and enough points to win the day outright! Neil also took out Class B for the event - his best ever result with the team.

FORMULA TASMAN
In the Formula Tasman stakes, Sam Dale almost didn't make it to the circuit - the alternator in his tow vehicle failed, and the battery held just enough charge to make it to Oran Park (literally - it refused to start after arriving at the track!). He did make it though, and it was with a very quick car straight out of the trailer.

Sam only completed four laps at the end of Friday's unofficial practice, but clocked a 43s laptime, putting him ahead of the rest of the cars that had been running throughout the day. Sam was grinning from ear to ear, as he had tried a number of new settings on his car, and ALL of them appeared to be working as planned, resulting in a more driveable, and faster car.

The trend continued on Saturday morning, with Dale 1 second clear of the next quickest car (Bob Muir's 550hp Lexus Reynard), with a 43.0s lap.

With a wide range of cars in the field, and traffic problems encountered in the practice session, Sam thought the best tactic was to be at the front of the queue for Qualifying, so he wheeled his car down to the end of pitlane well ahead of the session. One small problem with this plan though, the car had not yet been fuelled. So, just as the session was about to commence he fired the car up and promptly ran out of fuel. A jog for the crew back for some fuel, and the car was fired up with a few minutes of qualifying remaining. No time to muck around then. And Sam didn't, he waited for a clear lap, and put down a 41.8s lap - again leaving him a full second clear of the next fastest car, and with pole position.

The opening race was an eight lap sprint, with Sam on pole for the standing start. He made a strong getaway, and then proceeded to drive into the distance, enjoying the setup changes he'd made to the car, and finishing in the lead, 10 seconds ahead of second placed Bob Muir.

For the second race, Sam was concerned about the superior power of Muir's machine at the rolling start. He needn't have worried though - Sam lead away from the flag, and again pulled off into the distance to take the win. The threat from Muir was neutralised after a few laps when he retired with overheating problems, leaving the LM Sports car of Mark Laucke to take second.

For the third and final race - a 24 lap feature - Sam was again on pole for the standing start. Muir ran strongly in the opening stages, and Sam suffered a sticking throttle, causing the car to run wide on corner entry, and then not allowing a clean exit from the corners. This allowed Muir to close the gap, and actually pass Sam. A few laps later the safety car made an appearance, and picked up the car in third place. When the other cars were waved through, Muir mistakenly believed it was the restart, and proceeded to pass a number of cars under yellow flags. He was then excluded from the race, handing the lead back to Sam (patiently following the safety car). The race was temporarily red flagged, and then restarted with cars in the order they were stopped in (giving Sam another standing start from the #1 grid position). Sam resumed the lead, and wasn't headed - he took his third win for the day, and the overall win for the event.

TOURING CAR CHALLENGE
In the early running for the Touring Car Challenge, Mathew Fox set the 6th fastest qualifying time, with Neil Byers 7th fastest, the pair separated by just 15 thousandths of a second!

In the opening race, Fox came in 7th, with Byers 8th.

For Race Two, the first of the handicapped events, Byers reversed the order to finish 6th, with Fox in 7th.

For the third race, Neil finished 5th, with Fox recording a DNF with fuel pressure problems.

In the final race, Byers managed fourth place, while Fox was a non-starter with his fuel pressure problems.

Mumbo Racing's next appearance will be at the next round of the Independent Race Series at Queensland's Morgan Park 15 - 16 November.

Things I Learned From a Photo

Earlier in the year Mumbo Racing visited Wakefield Park for the opening round of the AMRC. The circuit had just been resurfaced, and I was looking forward to driving on the smooth, grippy tarmac.

The meeting turned out to be a little confusing, and it wasn't until I received a CD of photos from the guys at Oz Event Photo that I was able to figure out what had been going on.

It all started on the Friday unofficial practice. My usually reliable Reynard 94D suffered an overheating problem in the first session. One of the coolant hoses changed position slightly and came in contact with the alternator pulley - the pulley wore a hole in the hose, and the coolant escaped. Some quick repairs to the car on Friday afternoon had it up and running again, but I had missed out on some track time, and not really had a chance to get an idea about the circuit - all I could tell was that it seemed quite slippery.

On Saturday morning, the official practice session came to a premature end after the car continued to overheat - although the problem encountered on Friday had been solved, we hadn't been able to completely bleed to the coolant system, and the airlock caused the engine to overheat. We were unable to bleed the airlock out in time to rejoin the session. We were confident that the problem had been fixed though, and were looking forward to qualifying.

Well, qualifying came, and I had trouble coping with how slippery the circuit seemed. I completed a couple of uncharacteristic spins, that happened in a way I could not explain. I managed third fastest, but was disappointed with the time I had set, and unsure why I was slow.

Raceday came, and the first race started reasonably well. I moved up to third place, but on the seventh lap I spun part-way through the fish-hook corner. It felt like I was nowhere near the limit of rear-end grip when the rear lost grip and the car spin. In the course of making sure I moved clear of the racing line I stalled the car, and was unable to restart. I was out of the race. And out of ideas as to why I had spun.
Taking the final corner at Wakefield Park


In this case, and the couple of other spins I'd had during the weekend it seemed to happen in each case as I released the brakes. The car seemed to have quite a lot of understeer on corner entry, and just as rear grip should have been increasing (as I eased off the brakes into the corner), the rear would break away and I would spin. It didn't make sense.

I started from the rear of the field for the second race, and made my way forward to fourth before the earlier problem with the coolant hose reared its head again - the coolant hose was punctured and I was out of the race.

When I got the car back to the workshop, I solved the coolant hose problem very quickly - I fitted a bracket to keep the hose clear of the alternator pulley.

I was still pulling my hair out over the handling problem when the CD of photos arrived from Oz Event Photo. On the CD was the photo that appears above. As soon as I saw it something caught my eye: The front wing looks like it is touching the ground.

As soon as I noticed that I came up with a theory. I thought it may have been possible that the front wing was touching the ground under brakes. This would unload the front tyres, causing them to loose grip, leading to understeer. The understeer would only be present while the wing touched the ground (ie; under brakes). As soon as the brakes were released, the understeer would disappear, and the front tyres would be turned at a greater angle than normal (to overcome the understeer) - this would have the effect of very quickly moving the front of the car in the direction it was being steered, and possibly cause the rear tyres to exceed their maximum grip - ultimately leading to a spin. This sequence fitted exactly with what had been happening at Wakefield Park - just at the moment I would expect rear grip to increase (easing off brakes to transfer a little weight back to the rear), the car would spin.

Another sequence of photos from the CD showed the whole thing happening. Click here to view the sequence.

I thought there would be one easy way to prove this, and I raced to the workshop to have a look at the underside of the front wing.

The scars that proved the theory
Sure enough, a hole had worn through the underside of the wing where it had been contacting the circuit. I set about repairing the underside of the wing, and altering the mounting of the wing to make sure it was high enough above ground level.

So, how had this happened? I suspect there are two factors:

1) The wing had been a little low for a while but the increased grip on the new Wakefield surface allowed caused a little extra deflection in the suspension, allowing the wing to come in contact with the surface - more grip making it look like there was less grip!

2) I fitted new Yokohama tyres for this meeting - whilst they appear to have a very slightly higher sidewall than the Dunlops I had been using, it's possible the Yokohamas have a slightly softer sidewall, allowing more deflection, and allowing the wing to get low enough to contact the circuit.

Why didn't I figure it out sooner? With the other distractions (holed coolant hose, overheating), and limited track time, I attributed the spins to my own difficulty coming to terms with the new surface. It didn't even occur to me at the time to look at the underside of the wing - if I had, I probably would have figured it out.

Next time around, you can be sure the same mistake won't happen again...
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