I have been racing this car since 1990, and it has changed quite a bit since then. The lap times have tumbled down quite a lot, mostly due to the improvements made to the chassis, engine, drive train, and suspension

The car has run in a few of the Sports 1300 National Championships, and the results are -
- 1992, Eastern Creek. 3rd place
- 1993, Lakeside. Was running in 2nd place, then the throttle cable broke.
- 1997, Wakefield Park. Qualified on pole, but was just beaten so a very close 2nd place.
- 1999, Willowbank Raceway. 3rd place, with a friend guest driving in my place. (work commitments)
- 2000, Eastern Creek. On pole position for the race, but the diff blew on the line so a DNS.
- 2001, Willowbank Raceway. Qualified 5th on the grid, but the gearbox failed in the previous race so I could not compete.
- 2005, Willowbank Raceway. Qualified 5th on the grid but did not start the first out of the three races due to a minor engine problem. Did well in the other two to get third. Was easily the fastest car in class though.
- 2006, Oran Park. Qualified 1st in class, 5th on the grid but on the start line for the first race the gearbox broke and suspension also was badly damaged.
- 2007, Morgan Park, gearbox again failed in practice.
- 2008, Oran Park, finally finished all three races got third in class.

A quick link to the -
- Engine
- Suspension
- Brakes
- Chassis
- Wheels & tyres
- Gearbox
- Tailshaft & differential
- Thanks to ...
- Some links
- Some motorsport jokes. :)

Also please take the time to check out my New Racing Car. This one's going to be a lot faster, and this time it's not UgLy! :)

The car was the third one built buy Rick Choules, of Brisbane Australia, and the last. Unfortunately soon after finishing the car Rick's back & knees started to get very bad and so he couldn't drive it or build another. I bought it off him in late 1988, and my Father & I spent a year getting most of the 'fiddly' bit you need to make a racing car work, such as the special pistons, head gasket, etc. (The car itself was complete, but Rick hadn't got to build the race engine before he sold it to me - It only had a standard road type with all the external bits to make it look like a racing engine, at least!)
My first outing could have gone a lot better; The suspension was not set up at all and so was diabolical to drive. I spun halfway around a corner and clipped the gutter, damaging the nose. (I thought I could do a lot better because I had driven rally cars before that, so I reckoned a lot of the skills I'd learned off the road could have been applied on the track. Not so! It took me a number of years to get down to any reasonable sorts of lap times.)

Through the years the car has been developed so that is easy to drive 'on the limit' and occasionally beyond! The last major rule change the class had allowed the cars to have wings front & rear, so to get the best out of the car it has a fixed angle pair of wings on the front and a variable (In the pits only) angle wing on the rear. These have helped the cornering speed and stability noticeably. The other area of interest in the car is the engine - At the moment it a test car for a proposed new type of engine, the current cars being restricted to single cam two valve 1300cc types. I have a Suzuki Swift GTi 1300cc 16 valve twin cam in it with only minimal modifications to let it make about 135 hp with a rev limit of 8,000 rpm.  The old style engines are usually Toyota Corolla 3K 1200cc engines with 4 mm oversize pistons to take them out to 1294cc, and many other mods to get the same amount of power from them. Another common engine is the Datsun 1200GX A12, which has similar mods. Both these engines are a push-rod over head valve type, and have problems with longevity running at the 8,000 - 9,000 rpm's they need to make useful amounts of horse power.
So, the proposal was to introduce a modern type twin cam engine with minimal & restricted modifications to make the same level of power with much greater reliability and on-going costs.
The (major) proposed restrictions for the engines are-
- A compression limit of 10.25:1, thus allowing the use of regular petrol station 'premium' unleaded fuel. (The older single cams needed around 13:1 compression to make good power, and so had to use high-octane aircraft fuel only available at airports at great expense & effort)
- A rev limit of 8,000 rpm. Much the same as most of the small modern twin cams are as they come from the factory anyway.
- A maximum cam duration of about 270° and lift of 0.355".

** The Suzuki's were finally approved to run as of 1-1-99, so cheap racing is back with the Sports 1300's !
 

Also - The car ran in the 1999 Nationals, at Willowbank in Queensland, but I had work commitments and so couldn't drive it. So, a friend of mine, Dave Williamson, drove it hard to get a third place. Here he is at the end of one of the straights, after braking hard.

Ok, to the car.
The engine is almost as it came out of the road going car, the only mods that have been done to it are -
- A pair of longer duration & lift cams. (275°, 0.355" lift)
- A 'dry sump' system has been fitted to allow the oil system to continue to work even at the ~ 2 G's cornering & even higher braking forces that the car can generate.
- A pair of hand made free flowing manifolds for the inlet and exhaust systems.
- A pair of 45mm Weber side draft carburettors fitted.
- A lightweight alloy flywheel, clutch, and clutch plate fitted, total weight of all three 6kgs. (13lbs)
The rest of the engine is fairly standard, ie, the valves, pistons, crank, block, head & ports, etc.
The engine makes good power at all revs and doesn't have the peaky torque curve of the current single cam engines. The other benefit is that we think that the twin cam engines will be able to be run from five to ten seasons before having to be rebuilt - The current single cam engines will only run from one to two seasons and still be competitive. (And are far more expensive to rebuild!)
 

The dry sump system on the engine had to be almost completely hand made. The scavenge pump was fabricated from a large chunk of alloy, and has two sets of Holden V-8 oil pump gears in it. It pumps a heap more oil than the pressure pump the Suzuki has at the front of the crankshaft, and has to because of the foamy, aerated oil that comes out of the sump after going through the engine takes up nearly twice the volume of the oil going into the engine. The sump was also hand made, though the flange that bolts to the bottom of the engine block was retained from the original Suzuki sump and a new pan welded onto it to form the remainder of the sump.

The suspension at the front is a non-parallel unequal length double A-frame type, with an anti-droop set-up & no front anti-roll bar, and a Triumph Herald upright with Ford Cortina Mk1 brakes. The rear suspension is a five link, with four trailing arms and an under-slung Watts link under the Datsun 1000 Utility diff housing. Limited slip diffs aren't allowed, so great attention has been taken to keep both the rear wheels stuck firmly to the ground at all times. The rear brakes are from a Honda Odyssey 'fun 4-wheel bike' thing. All of the four adjustable rate shock absorbers have moveable spring platforms so the ride height and roll centre height of the car can be altered. The steering rack is from a Triumph 2000, as they have a very good turn-to-rack motion ratio. (In fact, it's reckoned that more Triumph racks are used in racing cars than in actual Triumph's!)
 

The brakes are 10" discs all round, work very well & are able to pull the car up at over 2 G's, and have twin master cylinders that are connected to the slave cylinders by means of braided stainless steel & teflon brake hoses. It has an adjustable balance bar to alter the brake bias from front to rear as required, though not whilst driving.

The chassis is a hand made 'one off'. Rick Choules made from 19mm (3/4") thin wall steel square tubing, with the alloy panels glued and riveted on to improve it's torsional rigidity. It has an 82.5" wheelbase, a front track of 55", and a rear track of 52". The wheelbase is very short compared to the track and would normally have very twitchy characteristics, but it's actually fairly tame to drive on the limit and can be thrown around and corrected easily. The car complete, ready to race weighs 391kgs, (862lbs) but with my long, tall body in it, it comes up to nearly 500kgs. (1100lbs)
That's still very light for a Sports 1300 though, most cars being 40 - 60kgs heavier - That's good.
I weigh up around 100kgs (220lbs) and most of the other drivers weigh 20 - 30kgs less - That's bad.
I'm also a little cramped for room in the car as it's wheelbase is only about 4" longer than I am tall - 78" or 6'6" or nearly 2 metres. I guess I'm used to it though ...

The wheels are a locally made 'spun alloy' three piece type. The fronts are 13x8", and the rears are 13x10.5". The tyres I use are Dunlop 195/490-13 on the front and 230/550-13 on the rear with both ends having the 271 compound, which is similar to what the Australian Formula Two racing cars use for wet weather tyre compounds. I run about 13psi in the front and 15psi in the rear for tyre pressures once the temperature has stabilised to normal running temps. The tyres can last as long as a season, but of course the faster you go the shorter they last. Some of our guys uses a set of fronts every two meetings!

Here's what was the old 5th gear, but is now 1st gear. If you look carefully you can see the modifications required to make the linkage work with the thicker gears, the modified selector fork, and the welding of the shortened mainshaft.

The other hassle was the gear selection mechanism. The original gearstick came out of back of the extension housing, and its motion was transmitted to the main selector fork shafts by another selector shaft between them. Since the extension housing was shortened a great deal, it was decided to cut another hole in the extension housing over the top of the main selector fork shafts ends and have a new gearstick come straight down into them directly. This was fairly easy to do, as all it involved doing was cutting the hole, inverting the main selector fork shaft ends, fabricating a new gearstick & mount, and also fabricating the lock-out mechanism.
The bottom of the gearbox has a large audio heat sink grafted on to help dump the heat into the airflow.
Complete, without oil, the gearbox weighs about 23lbs.
We ended up re-using only the gearstick knob off the old gearbox!

The diff housing was originally from a Datsun 1000 Utility, and has a alloy centre with a ratio of 4.111:1. We also have 4.3751 and 3.9:1 ratios if we ever need them. (3.9:1 is good for Eastern Creek, but 4.375:1 is good for Willowbank & Wakefield Park) The ends of the diff housing have large uprights welded onto them so the trailing links can attach and locate accurately. The Watts link sits under the diff and it's two arms go laterally to the sides of the chassis.

The standard Datsun 1000 diff centre just isn't strong enough unfortunately, so we had to build a four-spider diff pretty much from scratch. Hopefully it'll be bulletproof ...  and so far it has been.

** Slight change to the above paragraph - I had an 'off' in the car in late 1999, and we couldn't fix the nose in time, and it ended up being easier to build a completely new one. Turned out to be a good idea, as it's a lot lighter, perhaps a little more aerodynamic, and has about the same downforce as the old nose.
The cynics say that it certainly looks better! :)

Here's a picture of the car running around the Driver Training Center, at Norwell, on the Gold Coast. The new nose makes about the same downforce as the old one, despite having no wings.

 

Here's the racer at my first run atWillowbank raceway , west of Brisbane. Quite a slippery track and the car wasn't as fast as what I hoped it would be, but it still got very good results.

In times past, when going into Turn One at Willowbank I had to brake briefly but heavily, nearly go back into 4th gear, to get through the corner. Once the ratty old four-year old tyres had warmed up well enough I found that I could dive into Turn One without even braking, just a quick lift off the throttle. The engine also wasn't running as well as it has been in the past - It coughed and spluttered badly at medium revs and that slowed me greatly through and coming out of a couple of the slower corners. To cure that we're going to be ditching the 45mm Webers and fitting 38mm flat-slide Mikuni carbies.

He's not always of the best of health, so in years gone past we've had a lot of help from a few people; Ron Pomerell, Rick Choules, and Adrian Brooke.
Without those guys & their special talents & effort, the work would just not get done. Again, a huge thanks for their time.

This is the side of racing that most people don't get to see - the car in about a million pieces. We normally don't pull it apart as much as this, but it needed a good clean after the last race meeting at Willowbank and the gearbox was also playing up so it had to come out. To pull the gearbox out means that the engine also has to come out, and once those two are out there's not a lot left .. as you can see.

There's also some pictures of my New Racing Car.
To see more of the other cars in this class, check out Martin's Motorsport Page.
And there's also a big Clubman links page.
For even more motorsport links, try the motorsport section on my links page. 

On to Page Two, the car's rebirth 

But wait! There's more!!!
Top ten reasons Racing is better than Sex:
10. It’s socially acceptable to do it while others watch.
9. Bigger cars don’t always get the most attention.
8. The phone won’t ring in the middle of your race.
7. You get to use your rubber more than once.
6. You don’t have to sit through dinner and a movie before you race.
5. You and the car always finish at the same time.
4. You always know where to put your hands.
3. You can drive hard, right from the start.
2. The quicker you finish, the better you are.
1. You can do it more than once in one afternoon.

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