Last month CompleteCar.ie ran a story on the cost benefits of petrol powered cars over their diesel brethren that have become so popular in the CO2-based taxation age. After exhaustive research it was concluded that a new car buyer would take, on average, three years to recoup the premium paid for a diesel car over the equivalent petrol one.
The report was well received, but for a nation now attuned to diesel cars the notion that a petrol car could come close to the fuel economy of that of a diesel seemed alien. It is a long held belief in CompleteCar.ie Towers, however, that, while diesel technology has plateaued, that of the petrol engine is on the rise. You only have to look at the increased use of turbocharging and high-pressure direct injection to see this.
But quoting figures is one thing; actually getting out on the open road to prove the point is another and so I found myself undertaking a series of trips to try and clock up diesel type distances on a single tank of petrol. For this you may imagine I would use a petrol-electric hybrid or some other type of hyper efficient car, but my steed was instead a Volvo V40 T2 with a turbocharged 1.6-litre petrol engine that produces 120hp, 350Nm of torque and has an official combined fuel consumption figure of 5.3 litres/100km (53.3mpg) - not exactly ground breaking. My car was also an R-Design model, Volvo's answer to the Audi S line, and so included a high-gloss front grille, rear diffuser with twin exhaust pipes and a scattering of silk-metal details on the exterior - certainly nothing to affect my noble challenge. The 17-inch alloys may have had an effect, but this was countered by the sublimely comfortable R-Design branded leather sports seats that, over the course of the week, I became intimately aquatinted with.
I have done economy runs before; Skoda once got us to drive halfway around Ireland and back in a fleet of GreenLine cars to prove their efficiency and Opel sent us around Germany in an Ampera to do likewise, but this test was different. There was no prize at the end of it and no bragging rights over others in the bar afterwards; instead it was a chance for a petrolhead to prove that our beloved cars have been overlooked of late as more and more people 'buy the tax' of diesel powered cars that have benefited most from the switch to emissions based taxation. Sure the Volvo may not be able to match the emissions of it D2 diesel brother (though the Band B2 tax is still impressive), but under the right conditions and driven properly I was sure the V40 could do it.
A thought that was quickly banished when I looked at the 'kilometres to empty' display for the first time to see 645 kilometres. With a 410-kilometre round trip to Castlebar in Mayo, loaded up with two adults, two kids and a boot full of suitcases as we went on a family holiday it certainly did not bode well.
Thankfully, having only covered 372 kilometres up to that point the computer had not had ample opportunity to 'learn', as was proved when we arrived home from holidays with just under half a tank of juice and 425 kilometres showing on the display. While the remaining range was impressive it would fall short of the 502 kilometres needed for the second round trip to Kirkistown in Northern Ireland. Time to deploy some of the fuel saving tips learnt on the economy runs.
Though not too many of them; this was a real world test so speed limits were matched and with six hours in the car the air conditioning was left on. Instead it was a case of accelerating gently, watching the road ahead and braking and accelerating accordingly and free-wheeling down some of the steeper declines north of the border.
Upon arrival at Kirkistown the range showed 245 kilometres; just short of the 256 needed to get home, but also tantalisingly close to the 360 kilometres needed to hit 1,000km in the petrol powered Volvo. Dare I dream? Dare I hope that it was achievable? Best get home first!
Sticking to the self-imposed rules of 'real-world' driving was infinitely harder on the return leg as the kilometres began to seep away. "Killing the air conditioning would surely bring that lost 5km, as too would pulling in the wing mirrors and setting the cruise control for 110- rather than 120km/h." But none of these devices would be employed in a diesel car so they were out of the question. I did freewheel a little more on the way home than I had on the way out but as I habitually freewheel on declines anyway I did not class this as 'cheating' - some may disagree.
Despite my best efforts the low fuel light appeared soon afterwards with a large warning on the V40's digital display that I only had 115 kilometres worth of fuel left; enough to get me home but effectively banishing all thoughts of hitting the magical 1,000km. When I finally pulled into the driveway there was a mere 45 kilometres left, but exactly 100 kilometres to reach that milestone.
Something had happened on the return leg though; this was no longer a case of driving as far as I could before running out of petrol; I wanted that milestone. I would take that 45 kilometres, hope that after over 1,200 kilometres the computer was still learning and get 100 kilometres out of the tank; or at least that was the plan.
Positions of petrol stations were mapped out and away we went for the final push. And then something strange happened; that 45 kilometres soon became 50 and then 55. I was right, the computer was still learning; this could actually be done. Until I hit the M4 and the numbers began to head south even quicker. The motorway speeds were just eating away at the last remaining dregs in the fuel tank as 55 soon gave way to 45 and then 30. With over 60 kilometres still remaining, all of it motorway, I prayed to whatever deity there is for a truck or coach to slipstream, a decline on the motorway that I had not noticed before to freewheel down, anything to avoid that sickening 'cough' that would signify I was out of petrol and would have to call the AA to fuel me up.
Unfortunately, I didn't even get that far. As the kilometres to empty display ticked over from 30 to 25 the low warning light switched from orange to red (never a good thing) and the gauge that I had slavishly followed for nigh on 1,000 kilometres showed three dashes rather than numbers. The game was up - with no figures to follow I decided that discretion is the better part of valour and pointed the Volvo V40 towards the nearest petrol station for a splash and dash. As the car pulled onto the forecourt the odometer showed 1,326 kilometres - an agonising 46 kilometres short of the magical 1,000.
My wallet lightened by €10 and the gauge showing a healthy 140 kilometres to empty I continued on my way, deflated from the thought of being so close yet so far away. But then, the 1,000-kilometre mark had been my personal goal, not the purpose of the experiment. That was to get a petrol powered car to achieve diesel like range and at 954 kilometres from a single tank I had done it. Sure a BMW 520d EfficientDynamics will do 1,200 kilometres, but the V40 is not an eco-special with low rolling resistance tyres and other tweaks. It is an Audi A3 and Mercedes-Benz A-Class competitor fitted with a 120hp turbocharged 1.6-litre engine that had come within touching distance of achieving four-figure range from a single 52-litre tank of petrol. Ok so the 0-100km/h time was never tested and more time was spent looking at the digital display than the road ahead (sorry officer), but that is still some achievement and a testament to the advances in petrol engine technology that we have been banging on about for an age.
So when you are next looking for a new car don't just head straight for the diesel option; take the petrol powered car for a spin, do the sums and see how long it will take to recoup the diesel premium rather than just buying the one with the lowest road tax and then make your decision. And if you are in the market for a premium hatchback give the V40 a good look; it is a hugely competent and well specified car for the money - just avoid 'my' one; only my butt will fit in that groove.