I’ve always loved going to car wreckers, looking at the bits and pieces available so cheaply and wondering how I can integrate them into my car.

I started visiting wreckers when I had my first car – a 1973 Honda Z. That was way back in the early Eighties. I remember looking through the field of dismembered wrecks, finding dash parts from Honda Civics that I could shoehorn into the Z. I even integrated the high beam flash stalk from a Datsun 260Z into the little Honda.

Time passed, and I was then looking at wreckers importing Japanese engines and transmissions…. That led to a turbo 660cc 3-cylinder engine going into my Daihatsu Handi, and later an RB20DET turbo six going into a C210 Skyline.

I have been musing over this because in the last month I’ve been spending a lot of time back in wrecking yards.

I’m lucky enough to have discovered a wrecker of the old school, one that lets you wander around the yard of cars, spanner and pliers in hand, able to take off whatever parts you want and then take them to the front counter to have them priced.

But the big difference now is this: with modern hi-tech cars having been around for literally decades, the sheer variety of the parts that you can buy is amazing.

Need an idle speed control valve (as I did the other day)? Well, at this yard you can chose between Bosch (three types), Nissan, Toyota, Holden, Ford, Mazda – basically, every car in the yard has an idle speed control valve!

After half an hour of browsing, I walked out with a Bosch idle speed control valve from a BMW, complete with plug and a short section of loom. Cost? AUD$33.

Need a factory bracket on which to mount a GM MAP sensor? Sure – look under the bonnets of not only GM cars but also Daewoos. Cost? In this case, I was charged nothing!

Want some direct fire ignition coils? Would you like those coil-on-plug or remote-mounted? After a long look, I decided instead to go brand new with some Bosch coils – but the browse through the yard showed some very interesting approaches.

Need some 19mm hoses, preformed with bends to plumb a turbo blow-off valve? An hour later I walked out with no less than nine of them – all different lengths and bend radii. Cost? AUD$11. Oh yes, and that also included a rubber mount for the idle speed control valve that I’d forgotten to get earlier!

If you’ve not been to a wrecking yard for a long time, find a good one and have a long look around. You might be as surprised as I was.

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I hate making brackets that hold things driven by belts.

The last, most horrible job that I performed in this area was installing a supercharger on a Toyota Prius. I wanted to get the little blower mounted in a position where it could be driven by a longer version of the standard serpentine belt. This required painstakingly accurate building of a heavy duty and rigid bracket. The only place to put the bracket was where the engine mount sat – so the new bracket also became a new engine mount.

In itself that wasn’t so difficult, but getting the pulley mounted in exactly the right plane was just so time consuming.

However, in the end, the belt drive system (including a new idler pulley) worked perfectly – pity the supercharger was so noisy that it all had to come off again.

Right now I am building the bracket to place an alternator on a 2001 Honda Insight. (The Insight doesn’t normally use an alternator.) I don’t know if it’s just me, but this darn bracket is taking me forever.

The alternator is being located between the engine and the firewall, with access possible from both top and bottom. But the bolts on which the mount can ‘pick up’ are few and far between, meaning the bracket has to be a complex, odd shape.

Furthermore, it needs to provide the mounts for two idler pulleys. Why two? Well, they are needed so that firstly, there’s enough belt wrap around the crank pulley; and secondly, so that the belt misses the engine mount.

The resulting alternator bracket needs to be stiff, able to be installed (more difficult than it sounds when the fastening bolts for the bracket are on the side of the block, the end of the block, and under the block), and of course needs to be able to be built.

So how long is this taking me?

Including making a mount on which the alternator can sit temporarily as it’s juggled into the correct position, positioning the two idlers, clearing the torsional vibration damper on the driveshaft at full suspension bump, nestling the alternator as close as possible to the engine block, moving things around so an off-the-shelf belt will fit – and then cutting and welding 8mm plate, positioning the alternator drive pulley and the two idler pulleys in exactly the right plane, straightening bracket distortion after welding… well I’m still going on the bracket, and I reckon so far it’s taken me three full days.

I know I am a pretty slow worker, but three bloody days!

Anyway, the good news is that the top part of the bracket is now in position, the alloy engine mount has been milled to allow the plate to be sandwiched between the engine mount and the block without then causing a host of clearance problems, and as I write this, I am waiting for a belt that I think is the right size – better to have a belt on hand before I drill the hole for the second idler pulley….

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My Honda Legend is the heaviest car I have ever owned. As a fan of light cars, the Honda’s mass is not something that fills me with joy – but as described elsewhere, it was my best choice based on a variety of factors.

So does it feel unwieldy – even lumpy? No it doesn’t. Particularly because of the yawing ability of its all-wheel drive system, it turns-in readily and feels poised and amenable to directional change.

Driving the car, especially over bumpy roads, you can feel its favourably high mass / unsprung mass ratio: the body tends to float over the bumps rather than drop into them, and there’s never the feeling of the car being ‘shaken by the wheels’ that occurs in vehicles with a low sprung / unsprung mass relationship.

So is it all sweetness and light – the 1855-odd kg doesn’t matter?

No.

The Legend, despite its big brakes, is a car that requires clear effort to slow. Part of that effort can be seen in how quickly it blackens its front rims – even in gentle driving.

It also cannot get away from the disadvantages of its mass in fuel consumption. Particularly noticeable in open-road undulating terrain, the fuel burn when hauling its lard-arse up hills is high.

However, with lots of kg, a low Cd and relatively small frontal area, the Legend is a car that will roll a long way. Time and time again in the first month of ownership I have found myself committing that cardinal driver sin of going straight from the accelerator to the brake, rather than getting off the power sufficiently early that there can be a roll-down time in between.

I think it’s a good car… but I think it would be a better one at (say) 200kg lighter. That would have required all-alloy construction, something that another Honda I own (a first gen Insight) already has. (The – much smaller – Insight has a mass of just 827kg!) An all-alloy Legend I would guess at around 1600kg – still no light-weight, but more appropriate for its size and equipment level. I wonder why Honda didn’t do this? In the Australian market (at least) the car was underpriced compared to its Euro and Japanese opposition, so you’d have thought they could have worn the extra cost.

But whichever way you analyse it, the disadvantages of high car mass well outweigh(!) the advantages.

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Recently I read Thrust, the book by Richard Noble on his life in breaking land speed records, culminating in the development of the ThrustSSC car – the current world land speed record holder. The record was achieved in 1997.

The book is outstanding on a number of levels, including its honesty and clarity. The section where driver Any Green describes his techniques for steering the car is just amazing, as is the constant battle for funds that occurred every day of the project.

But one small part of the book particularly interested me: the section where the primary designer Ron Ayers describes how he went about designing the car.

The text is reproduced here:

How do you start designing a vehicle that is totally unique? Here are the characteristics of the problem that faced us:

1. By travelling supersonically on land we would be exploring a region where no-one had ventured, where even the problems could only be guessed at, so there were no known solutions.

2. As the aerodynamic forces involved were so enormous, any accident was likely to be fatal.

3. The project would always be underfunded, short of people and time.

4. There would be only one chance. The final car was also the first prototype. The first lines drawn on paper could well be the ones that are made. The very first assumptions and decisions, if incorrect, could put the project on the wrong track and there would be no chance of starting again.

Problem: how do you make those crucial first decisions when so much is uncertain?

First, every decision had to be a robust one. That meant it couldn’t be invalidated by subsequent decisions.

Second, we could only use technology we were very confident with. This militated against using the very latest technology in some cases.

Third, although direct experience of supersonic travel on land did not exist, we consulted widely, with aviation and automobile experts in industry, universities and research establishments. Experience with Thrust2 was invaluable, particularly in pinpoint¬ing practical and environmental problems that might otherwise be overlooked.

Fourth, where possible we left room for adjust¬ment or change, so we could incorporate knowledge acquired subsequently. Nothing was “hard wired”. One reason for using a steel chassis was that it could be modified if necessary.

Fifth, we didn’t try too hard to integrate the systems. If we needed to change one of them, we didn’t want to be forced to change them all.

Sixth, our choice of a twin-engined car made the design massively overpowered. Thus weight was not a critical factor.

The design resulting from such an approach must necessarily be “sub-optimum”. A second attempt, incorporating the lessons learned, would undoubtedly be better. But the design was proved in practice, and there was little about the basic concept that would need to be changed.

The more you read those notes, the more you realise the clarity of thought being employed: it’s also food for thought for anyone building a unique design of anything.

Noble and Green are currently involved with another land speed record car bid – the Bloodhound SSC.

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In my hand right now I am holding a bolt.

More specifically, it’s an Allen-key bolt (sometimes called a ‘cap screw’) that’s 30mm long and 10mm in diameter. It uses a metric thread.

It’s a high tensile bolt, which means – in plain terms – that it’s bloody strong.

I’ve just stepped over to the digital scales – it weighs 28 grams.

Now the reason that the bolt was sitting on my desk is that a moment or two ago I took it out of my pocket. And the reason it was in my pocket is that I’ve just stepped in from my home workshop, after finishing for the evening.

I’ve been building ‘Chalky’, my recumbent, full suspension touring bike that I hope to be one of the best human-powered touring machines in the world. Best for me, anyway.

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The other day I made a purchase that can only be considered an amazing bargain.

I first saw the goods (and then bought them) on Australian eBay, but by going direct to the manufacturer’s site, you can get them even cheaper.

So what am I talking about? Hose clamps – no less than 150 of them!

For just AUD$64.90 you get 150 stainless steel hose clamps to suit hoses from 6mm to 60mm. The clamps are packaged in boxes and appear to be of good quality.

And not only that, but you also get a flexible drive screwdriver (complete with three different sized socket bits to suit the clamps), a travel mug and a carry bag!

The company claims the retail value to be $240 – and that sounds about right.

The $64.90 cost includes postage to anywhere in Australia, and mine came delivered in a good quality cardboard box.

The deal is ‘while stocks last’ so you’d better get in fast!

Go here for the details.

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Over the years I have built plenty of simple structures that I’ve wanted to be both light and strong.

Those structures vary from little brackets that might be holding something in the engine bay, to complete human-powered vehicles that I trust my life to.

In all cases, the starting point for the design is to consider the forces involved. How does the force of gravity act on the structure? What direction do braking loads act in, or short-term transient loads like suspension forces? Will this tube be placed in bending (not so good) or is it being subjected to compression (good) or extension (better)?

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Imagine you were living in the late 1930s (and of course, a very small number of you may well have been!). Then, as now, cars had four wheels, a body, engine, suspension and brakes. But they often had something else as well – a chassis.

Nowadays, nearly all cars use monocoque construction, where the pressed steel body provides the required stiffness. The main exceptions are traditional off-road four-wheel drives and trucks and buses – these vehicles still largely use a separate chassis. A few bespoke cars also use non-monocoque construction; for example, a tubular space frame.

But even in the late 1930s, you could have seen plenty more designs that just a traditional chassis. Have a look at these – all are taken from The Mechanism of the Car, written by Arthur W Judge and published in 1939.

Firstly, we have monocoque (or unitary) construction. This Vauxhall retains a separate bolt-on chassis for the front suspension and engine mounts, an approach common in cars up to the 1970s.

But then we have the cast aluminium frame. What?! Yes, a car being sold in 1939 (the Hotchkiss Amilcar) used a frame formed from cast aluminium members bolted together.

Here’s how the cast alloy frame integrated itself into the car.

Then there was the tubular frame, as used by Austro-Daimler. The very large diameter central tube would have given both high bending strength and also resisted torsion.

And finally, we have a car that’s absolutely intriguing – and one I’d never heard of before. It’s simply listed as the ‘MG Racing Car’ and uses a backbone chassis formed from pressed, welded plate. The car also features double wishbone suspension front and rear – perhaps the first car to ever do so.

I think that these drawings are worth looking at closely (you can click on them to enlarge). In mechanical car design, there’s very little new under the sun…

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