350kW and 0-100 km/h in 4.6 seconds

Posted on March 24th, 2009 in AutoSpeed,Driving Emotion,Intercooling,Power by Julian Edgar

Today I was lucky enough to drive an interesting car.

A 2003 model AMG Mercedes Benz E55, it comes standard with a supercharged 5.4 litre, 3-valves-per-cylinder V8 boosted by a Lysholm compressor spinning at up to 23,000 rpm and pushing air through a water/air intercooler.

Which workshop will be the first?

Posted on June 9th, 2008 in diesel,Driving Emotion,Economy,Engine Management,hyundai,Opinion,Power,Turbocharging by Julian Edgar

Here in Australia, major car modification workshops are generally well established. That’s said in the light of full knowledge that workshops come and go; but equally, others build a strong reputation and live on for decades. Some even span two or three generations of the one family.


I know that you can always find customers to denigrate any workshop, but places like Turbo Tune in Adelaide, Nizpro and Beninca Motors in Melbourne, MRT in Sydney, ChipTorque on the Gold Coast, and Romano Motors in Brisbane are longstanding workshops with good reputations.


And I wonder which Australian business – either these or others – will be first: the first to realise that there’s money to be made in specialising in a new-age of car modification.

Muffler Design

Posted on March 4th, 2008 in Driving Emotion,Economy,Power by Julian Edgar

While car modifiers talk endlessly about exhaust systems, there is surprisingly little hard information about the design of exhausts, especially mufflers.

That’s why I was particularly interested to come across the text that follows, contained in – of all things – a book on corrosion of cars, published exactly 50 years ago. The chapter, by H. Silman of Electro-Chemical Engineering, is a great summary of exhaust muffler design.

The automobile exhaust system consists essentially of three parts:

(1) the exhaust manifold, which collects the discharged gases from the exhaust ports and conveys them by means of a pipe at least one-quarter of the diameter of the cylinder to the silencer,

(2)  the silencer, and

(3)  the tail pipe, which leads the gases to the rear, the side, or more rarely to the top of the vehicle.

Sometimes twin parallel exhaust systems are used, especially with multi-cylinder engines, whilst it is also becoming increasingly common for two silencers in series to be fitted, the second and shorter unit being located immediately before the final outlet.

The exhaust gases leave the cylinders of an automobile engine at a pressure of around 60-80 lb. per sq. in. and with a velocity of up to 150 ft. per sec. This results in a considerable volume of noise, which must be reduced sufficiently to make the vehicle inoffensive to the driver and passengers, and to the public at large. This legal requirement is achieved by allowing the gases to expand into a silencer chamber, where the intermittent and violent discharges of gas are broken up and emerge from the tail pipe as a continuous and relatively uninterrupted stream.

There are various designs of silencer, but they usually contain a number of baffles carefully designed to avoid excessive back pressure, which might result in a loss of power and overheating of the engine. There is always some loss of power resulting from the use of a silencer, but this need not exceed about 3% with a well-designed unit.

Power and torque

Posted on January 29th, 2008 in Hybrid Power,Opinion,Power,Turbocharging by Julian Edgar

torque-curve.gifThe (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.

How much (electric) power is needed?

Posted on January 8th, 2008 in Aerodynamics,Economy,electric,Opinion,Power by Julian Edgar

pug-trip.jpgA while ago I attended an electric car show held in Sydney. I made the 2000-odd kilometre trip in my Peugeot 405 diesel, a car that, incidentally, gained high Fives (in litres/100km) for the trip.

At the show I briefly sampled three of the home-converted electric cars – a very interesting experience. And on the long drive home to the Gold Coast, I had plenty of time to reflect on these cars.

The electric cars I drove each retained the original gearbox: the electric motor was bolted up to the ‘box and the ratios could be selected by the driver. Typically, the cars were started off in second gear and then third and fourth and fifth gears were used as appropriate. (I used first gear off the line and felt an immediate gain in starting performance.)

But none of the cars I drove had performance that came close to conventional petrol engine (or even commercial hybrids). Even when the electric motor was rated at a higher power than the original engine, the massive weight of batteries substantially dulled the resulting power/weight ratio.

Putting in a more powerful electric motor (or running two electric motors) would of course help solve that, but at the expense of greater electrical power consumption that in turn would need either more batteries or result in a shorter range (and none of the ranges were very good to start with!). However, all the cars could easily exceed the 110 km/h open-road speed limit.

Clearly, what is needed is an electric motor that has only enough power to do the job – but no more.

Driving Fast

Posted on December 11th, 2007 in Driving Emotion,Opinion,Power,Safety by Julian Edgar

derestricted.jpgYears 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?

Off the line…

Posted on October 19th, 2007 in Driving Emotion,Holden,Mitsubishi,Power by Julian Edgar

The week that I am writing this we have two press cars. It’s unusual to have two new cars simultaneously; in fact, it’s something I normally strive to avoid unless I am interstate for a period. Then it’s OK because those cars are usually not able to be obtained in my home state – so better to work harder for a short time in order to sample more.

One of the cars is a Mitsubishi 380 VRX 5-speed manual and the other is an automatic 5-speed Holden Epica 2.5.

Both are front-wheel drive but the 380 has 175kW and 343Nm in a body that weighs 1590kg, and the Epica has 115kW and 237Nm and weighs 1500kg.

Clearly, then, the VRX is going to be the faster of the two cars, not only because of its higher flywheel figures outweigh the slightly greater mass but also because its manual transmission has less losses than the Epica’s auto trans.

But is the VRX faster? Not a test in the world is going to show the Epica as being faster than the VRX (or the equivalent in other comparative cars) and yet as is so often the case, the power, torque and mass figures tell a story that is massively incomplete…

It so happened that my wife and I ended up in driving the two cars at the same time. I was in the Epica, she in the VRX – and in front of us a red traffic light. Both in pole position – and when the light turned green, we went for it.

Trouble is, the Epica was ahead all the way to 80 km/h…

Next red light, Georgina got a better launch – but she still took until 60 km /h to get past the Epica.

Simply, the power and torque of the 380 was so great that the traction control kept shutting down the engine as wheelspin occurred.

The same story could be repeated with lots of different cars – those with auto transmissions and insufficient power to break traction (or, to put it another way, a lower torque curve that extends further up the rev range) can be very quick off the line in real world conditions. On the other hand, manual trans cars with bulk off-the-line torque can be relatively slow.

I remember the disbelief when former colleague Michael Knowling wrote of an STi WRX that a Corolla was quicker away from traffic lights; an absolutely true story symptomatic of the STi being the opposite case to the VRX – no bottom-end torque at all…

No matter what figures might show, for real-world quick getaways, very little beats an auto trans matched to an engine that won’t spin the driving wheels.

Flywheel Energy Recovery System

Posted on October 12th, 2007 in Economy,Opinion,Power by Julian Edgar

kers.jpgF1 technology being relevant again to road cars? Surely not! An interesting series of press releases:

First application of mechanical ‘kinetic energy recovery system’ with major Formula 1 team

On the 5th June 2007 Torotrak Plc announced a licence agreement with Xtrac Ltd to use Torotrak’s traction drive technology to develop highly efficient and compact continuously variable transmissions (CVTs) for application in a new mechanical kinetic energy recovery systems (KERS) proposed for Formula 1 (F1) motor racing.

Further to this, Torotrak Plc is pleased to confirm that a major F1 racing team has become the first customer for the mechanical KERS system. This F1 team will be supplied with KERS technology through Silverstone based Flybrid Systems LLP, an innovative engineering company focused on research and development of hybrid vehicle technology, who will source Torotrak’s full-toroidal CVTs used in their KERS systems directly from Xtrac Ltd.

Dick Elsy, chief executive at Torotrak, stated: “the rapid movement from concept to application with a significant F1 racing team highlights the benefits of the mechanical KERS system and its ability to contribute to improved performance. This is also a significant step towards acceptance of Torotrak’s technology for use in mainstream road cars to provide improvements in performance, fuel economy and greenhouse gas emissions.”

Will the VE Commodore prove me wrong?

Posted on September 26th, 2007 in Driving Emotion,Economy,Holden,Makes & Models,Opinion,Power,Reviews by Julian Edgar

ve-commodore.bmpMost of our Australian readers won’t be old enough to remember the release of the 1978 VB Commodore – and to be honest, at the time I wasn’t taking much notice of cars myself. However, it was common contemporary lore that the VB represented the new, small and modern family Holden while Ford, with the XD Falcon, persisted with the larger, outmoded type of traditional family car.

With the increasing price of fuel, it appeared that Holden was onto a winner with the Commodore.

But in fact they weren’t onto a winner at all: the VN model of a decade later went to a larger – especially wider – body, initially perched on the narrow track of the previous series.

Most pundits would have thought – and in fact did think – that Holden was heading in the right direction with their smaller original Commodore. It seemed the correct car for the times and in comparison, the face-lifted XC that became the XD looked like a big mistake. (In fact, a few years after this, I can remember looking at an open XD wagon and wondering who on earth needed a load area so enormous.)

But new car buyers didn’t agree with the smaller VB-VL Commodore strategy – Holden would have sold more Commodores if they’d stuck with the larger body all the way through.

One reason I don’t think much of the Type R Civic…

Posted on September 24th, 2007 in Handling,Honda,Opinion,Power,Turbocharging by Julian Edgar

type-r-on-dyno.jpgToday I returned Honda’s Type R Civic to the Queensland office. I am quite happy to see it go: I think the Civic Type R is a pretty weak car – something I make clear in our road test that will appear in AutoSpeed in due course.

With a 2 litre naturally aspirated engine that revs to 8000 rpm and develops 148kW, it might look the goods on paper – but the reality is very different.

To go further, I think the idea that small, naturally aspirated engines can compete with turbo cars is the stuff of fairytales.

The Peugeot 206 GTi 180  and Ford Focus ST170 were similar cars in concept to the Type R Honda – all based around the idea that naturally aspirated, high revving engines have some intrinsic advantage over their forced induction competitors. That’s a purported advantage over turbo competitors that have more peak power – and vastly more average power through the rev range.