Racing the Rat (part3) An article in "Spare Parts"

(The magazine of the Constructors Car Club) 1 December 2007

In Part 2 I had just run the Road Rat in the Alexandra Hill climb. The next event that I went in was an Autocross organised by the Mitsubishi club at the Slipway (7/7/07). This venue is amazing. It is the flattened off top of a ridge in the bad lands South West of the Brooklyn wind turbine. Once it had been the end of a top dressing airstrip. The landowner reshaped it a bit and had it tarsealed to make a motorsport play area about half the size of a football field. Mostly it is the venue for drifting and a google search on "slipway drift Wellington" will bring up plenty of examples of this. Bundles of tyres line the edges of the area and other tyres are used to mark out a track. Shipping containers are stacked up to make a bridge over the entrance to the competition area and serve also as a viewing vantage point. It is a very functional facility and only 10 mins from Willis Street. The Autocross was set up as two laps round a course that was basically a long oval with some wiggles down the straights. Everything was great except the weather. There was actually some snow for a few minutes, but mostly it just drizzled all the time. I was getting good enough grip on the wet tarmac for accelerating, but pretty much none for steering, so a typical run was point in the general direction and squirt until the need for a directional correction loomed up through the mist and spray.. deal with that using handbrake as necessary, reorientate and squirt again. One problem was that the windscreen tended to fog up and I found that strapped in with the racing harness I couldn't reach to wipe it. However.. if I was having a few problems, others must have been having worse ones as at the end of the day I was 5th in a field of 16 starters with only one non-4WD ahead of me (and that was Webster who is usually ahead of everyone anyway).

Slipway Youtube vids are at...


As I mentioned previously, I was having trouble with the handling of the car on the track in that it understeered a lot under power coming out of a tight corner. So I set out to make an anti-roll bar for the rear end. It already has quite a stiff anti-roll bar at the front, so I tried all sorts of experiments with jacks and long leavers to get some idea of how much stiffness I needed at the back to keep both front wheels on the ground at about 1G lateral acceleration. All came to nothing... too hard. So I just bought a length of 16mm high tensile steel bar and 4 rose joints and found a place just above the clutch where I could get the bar to go across from one side of the car to the other and cobbled something up. I made the bar by welding arms onto each end of it. After I had made it, Phil kindly informed me that welding onto this steel was not a good idea and it might snap off at the welds. So I set up a jig in the garage and with a 3m long arm I bent the bar in the direction it would work in until it yielded. This was at an angle that was more than it was likely to experience in the car, and it didn't break, so I reasoned it would be OK, and bent it back to the right shape. It looked the part.. but did it actually work? Only one way to test it.

Next up for me was the Intermaque dual car sprints at Manfeild on 19th August. The car wasn't going all that great. Wendy organised a sealed Motorkhana the weekend before, and I found I had done a poor job of bleeding the brakes just the day before to the extent that the back ones weren't working. Also, the engine had started to blow a lot of oil out from everywhere so I had to mop it all up off the engine between each run. Anyway.. the show must go on, so I did a proper brake bleeding job and fashioned an emergency high capacity oil breather the full size of the oil filler fitting to help reduce crank case "air" pressure. I figured that this problem was mostly due to an inadequate cylinder hone job that I had had done on the engine last year, and I would have to replace the pistons and cylinders at some stage... but not yet! I A-framed the road rat up to Manfeild, just to play safe, and it all worked out OK. Had a great time sparing with Garth Hickling in his Seven. The cars were pretty well matched but with my hard old tyres and oil misting all over them the Rat was not doing at all well in the corners. I lost it at the hairpin once and almost lost it 2 or three times most laps. So Garth's car was generally viewed from the rear and with the image progressively getting smaller. My best lap was 1:32 which was a second better than I had achieved in the HCCC sprint meeting earlier in the year.. so something was working better I guess. I think the rear roll bar helped. Have a look at the two similar photos accompanying this article. They are both taken at the hairpin. The February photo is without the rear roll bar. You can see the suspension is pushed down more at the rear and the front wheel is in the air. In the August pic the car is much flatter. Thanks Dave Beazer for this shot. I think this shows that the roll bar is working. On the other hand, maybe I was just going slower.


So I had to deal with the oil problem. I found a set of pistons and cylinders in NZ that a friend had imported but decided not to use as he had changed his plans and was now building a 200+hp VW engine and these pistons were not quite up to that. They were slipper pistons and lighter than normal pistons because they don't have a full skirt. Ideal. So I bunged these in. Easy to say, but this is days and days of work. And not helped by the extra complications of oil catch tank (made for me by Phil.. thanks buddy) and anti roll bar, all of which has to be removed, along with half the bodywork and just about every damn mechanical part of the car just to get to the engine. Anyway, I got this all done just a few days before Wendy had organised a Club event at the Slipway. Great. So I ran the car about to make sure it was going OK and everything was looking sweet until I booted it up the Makara hill and suddenly this awful knocking started at one side of the engine and rapidly migrated to the other side as well. It was an odd sort of knock.. it made more noise on overrun than on power and was quite quiet at idle. I idled and coasted home.. put the car in the garage and sulked for 24 hours. The next morning (the Slipway day) the All Blacks lost to France and the weather turned nasty causing Wendy's Motorkhana to be rained off. What a depressing weekend!

I hopefully checked the valve gear, but there was nothing amiss there. So, ho hum, here we go again. Off with all the bits again, out with the engine, onto the engine stand and pull the jugs. Dopey me. Slipper pistons have shorter gudgeon pins, because the piston is narrower at the base than standard. But I had forgotten that and used my same old tefflon buttons to locate the Gudgeon pin instead of circlips. The Teflon buttons were too small and wrong anyway for this application and some had got twisted and chomped up and fallen out allowing the gudeon pin to slide to one side and start to cut a groove in the cylinder wall. Then the pin had become free from one half of the piston, and when that happened, the knock started. I guess if I had pressed on with full power the pistons would have broken and that would have been that. But, as it happened, I think I have got away with just a new set of pistons, pins, rings and barrels. I mail ordered these from the States, together with a few other needed bits including a kit for installing an oil seal on the fan pulley end of the engine. This cost about NZ$460 including freight. It took just on a week to arrive and I got everything going again in time for the Admiral Road hill climb on November 4.

"The Admiral" is a classic event of very long standing. It is located just East of Gladstone and the Wairarapa car club have been running this event for over 50 years I believe. Aaron Slight, on TV's Torque Show, announced it to be his favourite hill climb as he punched some BMW or some other flash thing round some now very familiar bends. It is a proper hill climb, up an actual hill, a narrow country road with tight bends and lots of camber. Good Road Rat territory. The event was very well run by the very relaxed 'Rappa CC. Ewart Anderson was there with his Mini and beat me by 0.2 seconds. That's an improvement; Ewart beat me by 3 seconds at Alexandra Rd. I was 10th overall out of a field of 14. I really recommend this event if you have any inclination to give a hill climb a go. And, yes there is a vid on Youtube, in case you might ask.

Link to the RoadRat's run up the Admiral on Youtube

The time has definitely come to start considering some better rubber. A friend gave me some 99% worn out semi slicks, ideal for a few more laps at Manfeild, but not road legal. Then I bought a pair of Yokohama A048s (road legal) tyres off trademe. Trouble is, when you start down this road you need to have spare wheels as well, and by chance I noticed 4 wheels of the right offsets etc on trademe and bought them. Plus a dodgy pair of wheels that I might be able to use on the front.. with spacers. Now I have way too many wheels, and I'm not quite sure what to do with them all... but at least I have some options now.

What next? I'm not sure... mostly I just want to run the car round a bit to regain some sort of confidence in it's reliability because quite frankly, I've had quite enough pulling it to bits for a while. But I'm also keen to try some events on gravel.

Link : Racing The Rat Part 2

Link : Racing The Rat Part 1