Car Advice

2008 Skoda Roomster Comparo - Petrol vs. Diesel

March 26th, 2008 28 Comments

2008 Skoda Roomster Comparo

Petrol vs. Diesel - Round One

Models tested:

Skoda Roomster 1.6 Petrol (automatic) $29,290 - Tested
Skoda Roomster 1.9 Turbo Diesel (manual) $28,990 - Tested

Options:

Metallic Paint $540 (Fitted); Park Distance Control (Rear) $690 (Fitted); Alarm System $530; Roof Rails $330 (Fitted); Panoramic Roof $1690 (Fitted).

- by Matt Brogan

The funky Skoda Roomster is no stranger to the CarAdvice office having been reviewed by Karl some months ago. So rather than review it again, I used the Roomster as a little science project to help solve the most important conundrum of the modern age – petrol versus diesel.

Through your comments and feedback, we’ve found a lot of people were unsure of the pros and cons of each engine type and were often curious as to the difference in the economy and drivability offered between the differing power plants.

With that in mind, I’ve set out to tackle a few makes and models of car (including a Minivan, Small Hatch and Mid Sized Sedan) against each other over the next two months to try and advise buyers which engine best suits their needs.

Perhaps by way of explanation it’s prudent to start with the obvious question of what exactly the power and torque figures mean in relation to an engine’s output and how these figures apply to real world driving when selecting a petrol or diesel fueled car.

To understand the figures, I’ll first try to simplify the often baffling difference between power and torque with a quick explanation of each term.

Power, to us of the metric age, is measured by the unit of kW (kilowatts) and essentially refers to the rate at which torque is produced. In the early days, an engine was measured in relative terms - how much work it could do as compared to a horse - thus the term horsepower (hp) came in to being.

The definition of horsepower is simply this, one unit of horsepower is the force required to elevate 33,000 pounds the distance of one foot in one minute. Translated in to metric terms it becomes a little messy, but in very basic terms more horsepower means more speed.

Torque on the other hand is an often over looked part of the equation, but is nonetheless very important, especially in the case of a diesel engine that more often than not will produce less power than its petrol siblings. Measured in Nm (newton metres) or ft lbs (foot pounds) in the old days, torque is a unit of measure used to describe the turning or twisting force an engine produces.

When the piston (linear motion) is applied in the case of an engine through the crank shaft (rotational motion) the torque or rotational force figure can then be calculated by use of a fulcrum from the centre point of the crank.

Think of it as a lever placed on the engine’s crankshaft measuring the force produced (note that time is not a factor – torque can be constant). In basic terms again, more torque means greater pulling power.

So with the physics lesson over, it’s time to see how all this is relative to selecting an engine, and what it means in real world terms so far as driving one, and indeed what running one will cost you.

My first guinea pig was the petrol variant, in this case the Roomster Style 1.6 litre four-cylinder. The double overhead cam sixteen valve engine revs rather freely and like most petrol engines, develops the majority of its motivation higher in the rev range.

The multi-point injection set up helps develop a rather smooth 77kW which is on board at 5,600 rpm, just shy of the red line. Coupled with a somewhat lack luster torque figure of 153Nm @ 3,800rpm the figures don’t really do a lot to inspire a would-be buyer, at least on paper.

Fortunately for the petrol Roomster the transmission is its saving grace, which is why I chose to review the automatic. In my opinion it does a better job than the manual when mated to this particular petrol engine, and made for a fairer comparison to the TDI model.

The six-speed automatic (with sport mode and tiptronic style shifter – floor mounted) adapts itself to your driving style and very quickly learns how best to react to throttle input selecting the required gear to keep Roomster moving at a respectable pace.

At first drive it seems a little slow, almost frustrating, but after a half-hour or so you very quickly notice the dynamics of the vehicle’s performance have changed - for the better - and that it is now moving with a lot more fluidity.

It’s not fast, it’s not meant to be, but it does get along rather well considering what’s under the bonnet would be more at home in a small hatch than a 1,210kg people minivan.

Around town it’s quite friendly, and although it is a tad slow for my likings, will keep with traffic easily enough. You’ll notice a lot more throttle input is required to maintain pace, especially in stop-start traffic or hilly areas but in all the car moves well enough not to present any issues.

The climate control has little bearing on performance or fuel consumption and does a great job considering the area it needs to cool/heat and the panoramic glass roof. With only two people on board Roomster manages hills rather confidently, but load in a few more people and their kit, and the petrol engine soon becomes a little asthmatic.

Moderate to larger hills, especially at highway speeds, requiring a lot more throttle input to maintain speed, and steep grades knock the stuffing out of it requiring low gears and a lot of revs to keep things moving along. I should imagine towing would also be an issue here though the test vehicle was not fitted with the optional 1,200kg (braked) tow kit.

Given the extra right foot required to keep things moving, the fuel economy soon starts to suffer and with the best intentions of getting the most from our test candidate, I could still only manage 9.9 litres / 100km for my week of combined city and highway driving (1,000km for each car), 2.2 litres above the claimed ADR results.

Moving on to the diesel now, the Roomster Style TDI comes in one guise only, the slightly higher capacity 1.9 litre five-speed manual. The single overhead cam eight valve turbo charged oiler manages 77kW, just like its petrol brother, though the power comes on sooner - 4,000rpm due to the low revving nature of a diesel engine.

The upshot of this is a tidy 240Nm of torque from just 1,800rpm which means minimal turbo lag, and linear, consistent pull in every gear – even fifth!

A little noisier at normal running speeds than the petrol, the diesel manages itself more confidently across a wider range of driving and can keep up to fast paced city traffic with very little effort. The extra torque on hand also means additional weight isn’t an issue and even when fully loaded I found very little need to down shift on all but the most precipitous inclines.

The pace carried is better than the petrol too. Maintaining speed is easier, highway cruising is more manageable, and the manual gearbox is simple, light to use, and is well geared for any situation you could possibly be faced with. Overtaking is easy enough and in most cases can be managed in top gear.

Perhaps most importantly the diesel came out trumps in the fuel consumption race (as you’d no doubt expect) returning 6.0 litres / 100km for the week. Although this was again over the ADR figure (of 5.5 litres / 100km) the difference is far better than that of the petrol, especially when you consider that the PULP fuel required for the petrol model and the diesel fuel for this model are roughly the same price, at least here in Victoria.

For my money, the TDI (diesel) is the pick of the litter. You’d really have a tough time pushing the petrol argument for a small capacity engine in a car of this size, and given the overall usability of the diesel engine – not to mention the economy gains – the choice is clear. Diesel wins this round.

Scoreboard - Diesel 1 : Petrol 0

Next month’s comparo will feature the Skoda Octavia.

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European driving - the right way

March 14th, 2008 58 Comments

Driving isn’t so a much a right as it is a privilege. That’s the issue we’re faced with in Australia and it’s part of the reason the greater majority of road users infecting our roads are incredibly poor at driving.

My recent venture through Europe highlighted several things that Australia seriously lacks when it comes to driving.

Firstly. The cost of owning a car and getting a license in Australia is very cheap in comparison to our European neighbours. In Holland for example, the public must only complete driving lessons with qualified instructors – not with a parent who has probably learnt a myriad of bad habits over the years.

Upon completing the scheduled number of hours with a driving instructor, a learner must then go through a rigorous driving test – again, unlike Australia. I recall my driving test was a 15 minute job. Part of the test included a point-to-point reverse – which I’m certain an ape of average IQ could complete with both eyes closed. To think that anybody could possibly fail a driving test in Australia truly shocks me and makes me wonder why they are allowed to hold a license.

Secondly. The mentality of drivers on our roads is beyond belief. Many drivers share the belief that sticking exactly to the speed limit is both safe for them and all drivers around them. In Australia, if you approach a driver sitting in the right hand lane, driving under the speed limit, they instantly get defensive and won’t move no matter what you try – this kind of mentality is unheard of in Europe.

The other thing that totally plagues Australian drivers is hidden speed cameras. Around Australia - in Victoria especially - the public is too scared to drive watching the road because of the risk of going several kilometers/hour over the speed limit - resulting in a fine from well positioned cash-cameras. Drivers are far too paranoid about their speed, so much so that they don’t bother watching the road in front of them. This results in inattentive driving, which is not only dangerous for the driver, but the people around them.

Our trip to Italy had us drive on many Autostrades. The Autostrades were limited to 130km/h. Take a guess how many people were actually doing 130km/h? You guessed it – not many. The majority of the drivers were sitting on a casual 150km/h, while the rest were happy to cruise past at 200km/h. In Australia, this would be seen as deadly. Government officials would be dumbfounded at how incredibly unsafe this practice is. Now take a guess how many car accidents we saw on the motorways during our stint in several European countries? 0. None. Zilch.

Why were there no car accidents? Because drivers don’t have an unfounded sense of pride when it comes to other drivers. There was rarely anybody who was in the left hand lane for longer than the time needed to overtake. The drivers are also trained to look ahead of traffic and spot any problems that are about to arise.

Arriving back in Australia was fantastic in many ways – after all, it is the best country in the world. But one thing that continues to amaze me is how bad Australia is when it comes to driving. It shocks me to think how many accidents are caused in Australia due to uneducated drivers that wholeheartedly believe that driving is a simple task that anyone can and should do.

I guess I’ll just have to bite my tongue – the Government seems to be far too focussed on ripping every last penny out of driver’s pockets via speed camera fines, opposed to actually thinking about ways to properly train drivers before they are handed a deadly piece of machinery which can potentially wipe out a family in a heartbeat.

- Paul Maric

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2008 Dodge Challenger production pics

February 8th, 2008 24 Comments

You might recall some time back we bought you news of the 2008 Dodge Challenger and some pre-production (or concept) pics. Well, build has been finalised and production is in full swing and so just because it’s so good looking, here it is again in all its glory.

Power output from the 6.10litre HEMI V8 is 325kW (in SRT8 spec - as shown) which if introduced in Australia along side Camaro next year could bring back the heady days of muscle car wars on our streets - look out HSV & FPV!

Phase III to fetch top dollar in Brisbane

February 4th, 2008 24 Comments

With an estimated selling price of $700,000 - $780,000 this 1971 Ford Falcon XY GT-HO Phase III ‘Bathurst’ Sedan is the highlight vehicle of the inaugural Shannons Brisbane Motor Show Auction.

To be auctioned on the afternoon of Sunday February 10 this icon of the local muscle car scene, the fastest four door sedan in the world in its day, is one of an estimated 150 remaining and has become one of the most collectable production cars ever made.

Volkswagen Passat R36 Brisbane Motor Show

February 1st, 2008 38 Comments

Volkswagen R36 Brisbane Motor Show

Volkswagen unveils the R36 at the Brisbane Motor Show.

Huge Phillip Island Classic planned for March

January 18th, 2008 1 Comment

The Phillip Island Classic is already the largest annual historic motoring event in the Southern Hemisphere, but this year all the stops have been pulled out to ensure that prestigious title is not lost.

Capped at 550 entrants, the Classic covers eight decades of motor racing history up until the late 1980s. The three day, thirty three event program will this year be based on the theme of Australian Legends.

Bikes join cars with record sales

January 17th, 2008 6 Comments

With car sales topping the one million mark this year, it’s not unreasonable to expect motorcycle sales to follow the upward trend.

The FCAI (Federal Chamber of Automotive Industries) figures show a 9% rise in bike sales bringing the total number for 2007 to 129,966 units, a new record.

Aussie muscle auction

November 16th, 2007 47 Comments

Okay, this is CarAdvice. Current cars, reviews, news, I know this. But like so many of our devotees, I too love Aussie Muscle and just thought I’d give our more nostalgic readers a very quick heads-up on an upcoming auction that may be of interest.

The big small car comparison

November 14th, 2007 109 Comments

Mitsubishi Lancer ES .vs. Honda Civic VTi .vs. Toyota Corolla Ascent Sedan .vs. Suzuki SX4 Sedan

One of the most hotly contested segments in the car industry is the small car segment. There was a time when small car meant Japanese car but European, Korean, and even American names are now entering the arena. But Japan is fighting back. The CarAdvice team looked at three newcomers and one slightly older model fighting to bring the small car crown back to the land of the rising sun.

There were a few surprises in the mix and the end result was far from easy to reach.

Victoria first to adopt ‘Lemon Laws’

September 25th, 2007 28 Comments

Victorian motorists could be the first in Australia to benefit from new ‘lemon laws’ to be implemented shortly by the State Government. These laws, although commonplace in many other countries (including parts of the US and Canada), have yet to make it to Australia leaving many of us feeling it is long overdue.

Under the proposed new laws, motorists who purchase vehicles that suffer repeated repairs on the same component, or endure a vehicle which is susceptible to the failure of numerous components over a set period of time, will be entitled to an exchange vehicle or full refund.

A problem must occur within a set time frame from purchase, which is yet to be determined, with the overall aim of the new laws being to limit the chance of a manufacturer repairing the vehicle repeatedly until the end of the warranty period, by which time the repair costs are then at the onus of owner.

It is believed, at this stage, the laws will only apply to personal buyers and the scope of the laws mean circumstances will alter depending on the severity of the problem. For example, if the nature of the fault directly affects a safety aspect of the vehicle, the manufacturer will have two chances to get it right. Should the problem be of lesser consequence, they may be afforded three or four chances to sort it out.

Lemon Laws also prevent the re-sale of dud vehicles without a disclosure of history to the new buyer.

Exact terms of the proposed laws and their passing by parliament have yet to evolve, but Consumer Affairs Minister Tony Robinson agrees that in all, it’s a step in the right direction and anyone (myself included) who has had to battle a big manufacturer to get what they paid for, will welcome the move whole-heartedly.

As always if you have any concerns or issues with your new vehicle, CarAdvice wishes to hear from you through the ‘Warranty Complaints’ tab at the top of the home page.