Unusually, in this blog I want to refer you all to the AutoSpeed article that was published today. As I have written above, I think it’s probably the most important article that we’ll publish this year.

So what’s it about?

In short, the article is based on a paper written by Dr Andrew Simpson when he was working for the Sustainable Energy Group at the University of Queensland. His paper looks at a huge number of alternative fuels and drivelines, concluding which are the best from both energy efficiency and greenhouse gas emissions perspectives.

Andrew has given us permission to use major excerpts of the paper, and in fact went through it again to ensure that his conclusions are current. The full paper can be downloaded from the link at the end of the article.

His is a detailed ‘well-to-wheel’ study, where the environmental costs of producing the fuel and the efficiency of the cars using them are evaluated. Even better, they’re all benchmarked against a real car, the Holden Commodore. Even better again, the alternative fuelled cars are modelled to have the same range and performance as the Commodore.

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I am starting to wonder how much people should spend on tyres.

Years ago, when I owned a Subaru Liberty RS, I bought a set of sticky track tyres of the type that were only just road legal. They gripped phenomenally well, even in the wet. Given the minimal tread depth, the latter was a real surprise to me.

And at other times I have also bought other very expensive tyres, largely being guided by brand name and word of mouth.

But now I am not sure that on cars of less than stratospheric performance, it’s worth spending a lot of money on tyres. Instead, I am starting to think that if there are problems with handling, the money should be spent on the suspension instead.

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The (repeated) articles that we’ve recently run in AutoSpeed on power and torque are vital to understanding how to make your car go harder.

(The series can be found at Power vs Torque Part 1 –  and Power vs Torque Part 2)

And why is this understanding vital? Simply because people who use the terms ‘power’ and ‘torque’ often don’t seem to really understand what the words mean. The vital point to realise is that engine power is worked out by multiplying torque by revs.  And that’s the only way that power is worked out!

So an increase in torque at – say – 2500 rpm will mean a proportional increase in power also occurs at 2500 revs. It’s therefore just plain stupid to say “there wasn’t any change in the power curve but we got an increase in mid-range torque…” as some manufacturers of performance equipment state.

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Every month or so we get emails from a readers suggesting that we take a look at a new engine design that’s been developed by a tiny company or even a single person. The reader sends a URL and the website invariably lavishes praise on the new concept, describing how it develops a greater specific power / better specific fuel consumption / is cheaper to build / etc.

However, I very seldom go ahead with a  story – in fact, the only one I have ever done was this one. But if we’re interested in covering breakthrough automotive technology, why wouldn’t we want to run every such story we can find?

The short and brutal answer is that 99.9 per cent of these ‘breakthroughs’ are failures. To put that ratio another way, we could run 1000 stories and maybe only one of those would prove to be on something that is commercially and successfully built.

I am well aware that innovators and inventers will complain that a lack of media coverage is part of the very reason for that lack of success. And I accept that point. But in an automotive technology magazine, the very first requirement for exposure is that the engine (or whatever ‘breakthrough’ it is) be installed in a car that can be driven. That’s why we covered the Scotch Yoke engine – one of the test beds for the engine was a registered and driveable Subaru Liberty sedan. (In a different way, that’s why we’re also happy to cover home-built electric cars – they can be driven.)

While of course dyno testing of power, torque, emissions and fuel consumption are a vital part of a new engine development, the performance the design achieves in the real world seems fundamental to any assessment.

The other reason that very few stories of this type of appear is that when small companies have real breakthroughs, they tend to keep it very quiet. Instead of having media interviews, they’re dealing in closed boardrooms with large companies, selling intellectual property licensing.  One example is the Kinetic Dynamic Suspension System (KDSS) – originally developed by Australian company Kinetic – fitted to the current Toyota Landcruiser.

On the other hand, major car and component supply companies often release detailed information on forthcoming designs. While some of these breakthroughs never go into production (or their long-term success is less than stellar) the ‘hit’ rate is not 1 in a 1000, but more like 900 in a 1000!

It would be a very brave or stupid person who suggested that major design breakthroughs are the province only of major companies, not individuals working on their own. However, in things automotive, I suggest that apparently groundbreaking new technology will be taken much more seriously if it can be convincingly demonstrated in a vehicle that journalists can drive and test.

Well, that applies for this journalist anyway!

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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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Years ago – say getting on for 15 or 20 years ago – people used to ask why I had a performance car.

“There’s no where you can drive fast,” they’d say, “so why bother?”

I’d enigmatically respond with something like: “Oh, there are still plenty of places left to drive fast.”

And, in those days, there were.

The Northern Territory had no open road speed limit, and while the other Australian states and territories had 110 km/h limits, the philosophy of enforcement was then completely different.

There were no speed cameras – all radars were hand-held and, a little later, mobile in-car. In most states, radar detectors were completely legal, and all police communications were unscrambled voice. Trucks didn’t have speed limiters and on the open road typically sat well over the speed limit. CB radios were constantly used by trucks to communicate the presence of police cars (“double bubbles”) and police motorcycles (“Evel Knievels”).

In my Commodore VL Turbo I ran a radar detector, CB radio and police scanning radio. And they weren’t there for looks.

My BMW 3.0si ran to an indicated 220 km/h, my Commodore Turbo to 210 km/h, my Liberty RS to 220 km/h (which seems slow but that’s what I remember), my Daihatsu Handi turbo to 180 km/h and my R32 GTR to 260 km/h. And none of these were figures I got from just reading a book…

Any tight, windy road was a challenge there to be taken: the chances of being caught were tiny. In addition, the speed limit for the stretch of road was seldom set on the basis of the corners, so it was common for a 100 km/h limit to be in place on a road that included corners with advisories down to 30 km/h.

In those days turn-in understeer at 150 km/h was a real consideration; lightness in the steering at over 200 km/h was a right pain in the butt, and anything less than 130 on the open road and you must have had Grandma on board. I remember I boiled the auto trans fluid in the Commodore when going for a top speed run – the car was slipping its clutch-packs and the fluid got so hot it came out of the breather onto the exhaust. A guy I know used to sit on 180 km/h on the open road, ear plugs firmly in place.

Without any doubt the roads today are much safer – I’m sure the enforcement of speed limits and low/zero blood alcohols have resulted in less fatalities and injuries.

But now there really aren’t any places to drive fast. These days, they literally put you in jail if you drive fast, and take away your car if you have a few quick traffic light races. I am not saying that’s bad; what I am saying is that the road use of a performance car is now so limited that I wonder at their purpose.

I live at the top of a steep and windy country road. There’s about 15 kilometres of it – and I know it far better than the back of my hand. I’ve at times driven it extremely quickly, but any time I have done so I’ve been risking my license – the speed limit is 60 km/h. At sixty I can go around every corner without slowing.

Apart from flicking through an urban roundabout quickly (so what…), there is nowhere – literally nowhere – that I can drive fast. And that’s living smack-bang in the middle of what many call the best drivers’ roads for hundreds of kilometres.

And is it any different for other people? I was in a workshop the other day and the proprietor told me how the Falcon XR6 Turbo out the front had 450kW at the wheels. Or was it 550? – I don’t know, I wasn’t really listening. The prop went on to say that it was a really hard car to dyno because of wheelspin. Apparently, on the road it wheelspins up to 4th.

Now, honestly, apart from dyno bragging rights, what is the point of having that much power in a road car? As I have implied, once upon a time it would have been really useful – 100 to 200 km/h in just a handful of seconds. But now, spinning wheels will cause a police booking, a quick traffic light race ditto, and exercising anything like the top-end potential would immediately result in jail time.

Wouldn’t it make a lot more sense for people to have cars so low in power that you can have fun at what can only be described as slow speeds? Or instead of spending money modifying an already powerful road car to make it even more powerful, invest in kart, budget open-wheeler or dedicated drag car?

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The car industry can be thought of as having parallels with the fast food industry. For example, Toyota is rather like McDonalds.

McDonalds is a company I’ve always found enormously impressive. For so long associated with the consumption of unhealthy food (every media story of obesity accompanied with a pic of a McDonalds burger) and gratuitous consumption (talk of “McMansions”), the company has in recent years undergone a wonderful metamorphosis.

You can now buy food as healthy as salads and apples; breakfast can be high-fibre cereal; and all is provided at the cost and quality (one low, one high) for which the company is famous. But, if you so desire, you can stick with the high fat fries and burgers – cos they’re all still available too.

Commentators have suggested that the McDonalds reinvention is all a façade, that the vast majority of people still eat the unhealthy food but they feel better at attending a McDonalds restaurant because there’s also healthy food available. The same commentators say that while some food looks – and is – healthy, by the time you add the available condiments, the scales tip the other way.

Both points are probably to a degree right, but in my view the company still needs to be congratulated for making a huge cultural shift in the foods it makes available to the public.

In short, it sniffed the breeze of social change and took decisive action.

And Toyota is much the same. Over a decade ago it looked at long-term cultural change and realised that it needed to produce some very different products. The hybrid petrol/electric Prius was the first result.

But, like McDonalds, Toyota didn’t disenfranchise its existing customer base: salty high fat Landcruisers continued (and continue) to be produced. The parallels persist: some commentators suggest that the Prius is really for people who only want to appear to be green; that the environmental reality is actually quite different. And that the hybrid Lexus 600hL is really a huge, fat and greasy burger – but with a low kilojoule dressing and sold in a green box.

Like other fast food franchises that originally laughed at McDonalds healthy food move (but now do imitation garden salads and low-fat health burgers), car companies that were once happy to state that hybrids were a dead-end fad are now developing or selling hybrid cars.

But at this stage, those ‘me too’ products lack the cut-through decisiveness of the originals.

Both McDonalds and Toyota have been bold and brave. They’ve copped criticism – some with an element of truth – but by their foresight, they’ve changed the product paradigm. Rather than being driven by their current customer demands, they’ve looked at their goods in a far wider social sense, innovating rather than defending the status quo.

You can see why, in a world context, both companies and so successful…

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Right now – and probably for the next few years – there’s a helluva bargain to be had.

I’ve bought one to put on the shelf and I highly recommend that anyone else into useable road performance does so too. And what should you buy? At least one of all those BA and BF Ford Falcon XR6 intercoolers that are being flogged-off on Australian eBay, commonly priced from about fifty bucks.

Yes, from fifty bucks.

Now maybe the people who want far in excess of the Falcon’s standard 240kW have an urgent need to replace these Garret-cored, bar-and-plate intercoolers with something far better, but for people who are happy to drive a car with performance not limited by wheelspin, these intercoolers look perfect. Being an all-welded design, they’d also be dead-easy to jacket with aluminium sheet, making them water/air intercooler cores. At a core size of 370 x 175 x 60mm, they’re relatively compact but have well-shaped alloy end tanks. For people wondering overall size, they’re 620 x 270 X 60 cm to the extremities. Inlet/outlet tube size is 58mm (hose ID).

Even if you consider the time and labour to fold up new end tanks from sheet aluminium and pay someone to TIG them to the original core, you’re still talking an excellent intercooler for the price.

The one I bought came with all its hoses and clamps – also very useful when you’re plumbing any intercooler into place.

Without having done any flow or temperature testing, but looking at the core and assessing the original application, I’d be happy running at least 200kW through them – more, eg 250kW – with a good water spray.

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I’ve written here previously about three wheel cars but recently I came across a very interesting article on the topic.

It was first published in US magazine Road and Track in May 1982 and is based around a report prepared for the National Highway Safety Administration by race car engineer Paul Van Valkenburgh. Van Valkenburgh, working for Systems Technology, Inc, was tasked with seeing whether or not 3-wheel cars had intrinsic dynamic deficiencies over 4-wheel cars. As in, do 3-wheleers really have a propensity for overturning, have uniquely (bad!) handling, and so on.

Excerpts from the magazine article:

He tested eight 3-wheelers, four with a single front wheel and four with a single rear wheel, and he compared them to four roughly equivalent 4-wheelers.

The first concern of those who insure, if not those who drive, 3-wheelers is the possibility of turning over. A theoretical dissection of the problem turns out to be less important than simple observation that one test 3-wheeler had better overturn resistance than the best 4-wheeler, a Fiat X1/9. Sound ridiculous? It isn’t if you look at the numbers. If you get the center of gravity (cg) low enough and close enough to the 2-wheel end, and have a wide enough track, you can build a 3-wheeler that won’t overturn in the most extreme maneuvers on flat pavement. Naturally, if you retain the identical cg location and track width of a given 4-wheeler, three wheels will provide a lower overturn safety margin. But these design parameters are never cast in stone and, in limited production, you can put the cg and track just about anywhere you choose.

To be honest, the 3-wheeler with the best overturn resistance was sans body, and therefore had an unrealistically low cg. But another 3-wheeler, fully equipped, was still almost as overturn resistant as the Fiat. Also, I should note that one of the 3-wheelers could have been overturned in testing and in fact was by its owner. It had a high, rearward cg and narrow track, and at 0.6g it would take up on two wheels, precisely as predicted from static tests. To a skilled driver, this was no problem, and it could be balanced there like a motorcycle as long as you had enough time, space and presence of mind.

But now I come to a philosophical question: Is a vehicle that will overturn during hard cornering “unsafe”? Perhaps it is even more of a legal question, as there are some current lawsuits trying to determine if Jeeps and other recreational vehicles are “unsafe” in overturn. If overturn in cornering is unacceptably dangerous, what about tall, narrow, commercial vehicles, such as loaded tractor-trailers, which can go into oversteer at about 0.3g and overturn at about 0.6g?

Even if I assume that engineers of 3-wheel automobiles would optimize the overturn design limits, I still need to know how their stability and handling compare. I will ignore the myriad ways of analyzing stability (static, dynamic, transient, steady-state, oscillatory, divergent, covergent) and just consider oversteer/understeer. Most car enthusiasts have an intuitive feel for these terms and respect for the potential dangers of unexpected oversteer at the limit.

As it turns out, there was a strong distinction between 4-wheel cars and single-front-wheel cars — but not single-rear-wheel cars. Although the sample was admittedly small, the inescapable conclusion is that all single-front wheel 3-wheelers will oversteer at their limit of adhesion. Conversely, all single-rear-wheel cars had strong understeer at the limit. And in neither case could the opposite effect be created, in spite of all the chassis tuning.

Conventional 4-wheelers have a constantly increasing steer angle as speed or g-forces increase. The same is true (to a potentially greater degree) with single-rear 3-wheelers. But the steering on single-front 3-wheelers levels off and then decreases with increasing g’s, requiring counter-steering to avoid a spin.

If these results were difficult to predict, they are easy to explain after the fact. Oversteer/understeer is a result of  many vehicle dynamics factors, such as tire size, type and pressure, suspension characteristics, steering compliance, weight distribution and roll resistance distribution. With all other factors being roughly equal, the end of the car with the greatest weight and greatest roll resistance (springs or anti-roll bar) will have the lower limit of adhesion. Put another way, a nose-heavy car or one with lots of its roll resistance up front will understeer, and vice versa for rear/oversteer. The implications are obvious. With a single front wheel, most of the weight is at the rear, not to mention all of the roll resistance.

On some of these 3-wheelers, extremes of state-of-the-art chassis tuning tricks were attempted, with negligible effect. Regardless of large tire and pressure differences, camber changes and changes in weight distribution that were reasonable from an overturn standpoint, they still oversteered. But again, is oversteer unacceptable? There are a lot of naive folks driving around out there in oversteering production sedans (because of low tire pressures) who will never encounter that limit even in an emergency. The fact of oversteer is easy to obtain; the implications are more than a little speculative.

So overturn can be avoided, and single-rear 3-wheelers have a comfortable degree of understeer. But what about handling — how do they feel? Professional researchers resist being quoted on subjective impressions, but at least here they report a numerical value for handling response. These yaw response times represent the time required for a car to reach a steady cornering condition after a quick steering wheel input. Ordinary 4-wheelers range form perhaps 0.30 seconds for a large car with soft tires, to 0.15 sec for sports cars. All of the 3-wheelers were below 0.20 sec, to as low as 0.10 sec. and that is quick.

The answer is not in the number of wheels, or their location, but in mass, tires and polar movement. The effect of polar movement has been considered for years, but this is the first report I have seen with actual figures. The 3-wheelers had, on the average, about 30 percent less polar movement (normalized for weight) than 4-wheelers, because of centralized masses and less overhang. And the ones with the lowest figures and best tires had the quickest response. Van Valkenburgh says that some of the 3-wheelers had yaw characteristics akin to those of formula cars.

All of the rest of the tests showed no measurable difference between 3- and 4-wheelers. The testers subjected the cars to crosswinds, bumps in turns, braking in turns, free steering return, lane changes and off-camber turns, and although there were many vehicle-specific problems (as you would expect with one-off prototypes) the number of wheels was unimportant.

The technical problems involved in producing a practical 3-wheel car do not appear to be overwhelming. And the potential benefits of cost and fuel conservation would seem to make it worthwhile. As Van Valkenburgh succinctly put it, “a properly engineered 3-wheel car can be made as stable as a properly-engineered 4-wheel car.” But recall your initial reaction to the questions of stability and handling. The big problem is psychological — market acceptance of a radical change. Even if the 3-wheel layout were twice as good, I wouldn’t speculate about its future. One of the most powerful forces on earth is the inertia of an existing idea. But if 3-wheelers ever have a chance to make it, their time is now.

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