Firstly, a little bit about me. I’m Dominic and I work as a Systems Analyst. I’ve always been a bit of a petrol head. My first car (bought before I even had a licence) was a 1965 Honda S600 Coupe. That’s a tiny little sports coupe with a DOHC 600cc motor and quad carbies. I eventually owed a variety of S600’s and S800’s – none of them really in full working order.
About then, I bought a house, got married, changed jobs, and needed to give up on toy cars for a while. Years later, when another house move gave me some real workshop space, it was time to get back into having a car that was purely for fun.
In 1997 the book Build Your Own Sports Car for as little as £250 was published, with detailed plans for building a Lotus 7 “replica”. Reading that book, plus some internet searches, led me into a very active local and international community of people building the “Locost” described in the book.
Talking to them and seeing some of the cars being built locally gave me the confidence that I could probably go even a little further and draw up my own variant. And that’s how the Gecko Project was born.
The basic plan was this: take the traditional Lotus 7 or “Clubman” layout – small, open 2-seater, with exposed front wheels etc – and update it for the 21st century. Mostly that meant using a more modern drive-train and mechanical layout. The end result is something like a Lotus 7 crossed with an MR2 – 4-cylinder front wheel drive engine and transmission mounted directly behind the seats, driving the rear wheels in a mid-engine configuration. The Clubman shape is distinctive and I was nervous about messing with it too much so I initially made a 1:6 scale model to make sure the end result would look all right.
After more than a few hours with the sketch pad and calculator, I ordered 50m of 25mm square tube and bought a MIG welder. A TAFE course on welding plus plenty of tips and guidance from some of my new found car building friends had me confident that I could at least tack weld. After tacking together maybe 20% of my initial chassis design, it became obvious that I hadn’t fully thought through a number of design decisions and I eventually cut up that first version up. Version 2 incorporates a lot of things I learned from v1 and from further research. If I ever build a v3, it’ll be better again!
In Australia, home built vehicles like this are registered as ICVs – Individually Constructed Vehicles. This also covers things like Cobra and GT40 replicas and so forth. Somewhat frustratingly, even though there are national standards for ICVs, the individual states see fit to impose their own variations. In QLD, things aren’t too bad, relatively. The main problem is proving emissions compliance, which needs to be to ADR37/01. The most straightforward way to do that is to use a 37/01 or later engine, and that (basically) means Australian delivered from Jan 1997 onwards.
The other big piece of compliance work is proving that your chassis is strong enough. This is done by setting it up in a test rig that tries to twist one end with a beam loaded with weights while the other end is bolted to the floor. The required minimum is 2,400 Nm/degree of stiffness. The book Locost design mentioned above doesn’t come close to meeting that without significant mods. There was much nervous waiting until my chassis test results came back from the engineer.
Final result? Over 5,800 Nm/degree!
The current status
I mentioned before about emissions compliance. When I first started building the car, I bought a 20-valve “Silvertop” Corolla twin-cam motor and gearbox. These Japanese market only motors are popular in Clubmans here and were, at the time, relatively simple to get compliance for. After I was well under way with construction, having already built all of my rear suspension around Corolla parts and dimensions, the goal posts started to shift and it looked expensive and/or difficult to prove the silvertop compliant. On top of that, QLD Transport were even making noises about requiring even later compliance, ADR79/00 (that change never eventuated though).
After some serious thinking, I decided to buy a newer motor and picked up all the mechanical bits from a lightly rolled 2006 Lancer. Because it’s dimensionally different to the Corolla and has different CVs etc, I’d need custom axles made to join everything up but that looked doable (for some money).
However, more recently, as I’ve started to unpick the wiring loom, problems began to appear. The issue is that, like most modern cars, the Lancer uses a tightly integrated electronics system with the ECU, ABS, Anti-theft, Instrument panel, etc all talking to each via a CANBUS network and none of it happy if any of the bits are missing.
I could spend quite a bit more money (and lots of time) tracing and defeating all of the various CANBUS issues. Or I could buy an aftermarket ECU which would still need to be wired and tuned and wouldn’t actually meet the approving engineer’s’ requirements. Thinking laterally, I realised that the AE101 and AE112 Corollas have the same dimensions as the Japanese silvertop parts I’d started with and their 1.8 litre 7A-FE motor is not actually a bad little engine. More importantly, they’re from before CANBUS and all that fun. After some patient searching online, I drove home a cheap ‘99 Corolla a few weeks ago and stripped it for engine, gearbox, and all electronics. The drivetrain drops into the rear suspension I’ve already built, using standard axles. The biggest part is making new engine mounts, which will be a few hours with the grinder and welder.
So, that’s where the story is up to for now. Comment below if you want to see more, I’d be happy to provide an update later this year once the Corolla motor is in, wired, and running!
And why “Gecko”?
That’s easy – Gecko’s are small and quick and have sticky feet, like any good sports car should!