Diesel has been shuttling cars around day to day at a surprising rate of pace for some years now. Its always given a gratuitous low down kick in the back that oil burning Golf driving Dads snigger at when the GTi next to him struggles to hang on for a few brief moments.
Jokes aside, in more recent times manufacturers have made decided strides toward turning diesel into a more serious fast car fuel.
BMW, Volkswagen group, JLR and others have spawned veritable oil burning rocketships for the masses. Different turbocharging technologies and leaps in ECU development have made for machines that can give rev hugging N/A belters of yesteryear a real run when the cogs get swapping.
Audi has adopted the controversial fuel in conjunction with hybrid e-tron tech for its Le Mans racers in the name of efficiency and more spread out fuel stops to a devastating effect.
In my own experience, a Seat Ibiza Cupra 1.4 (turbo and supercharged) had little on its effortlessly punchy FR TDi stablemate. Whether thats down to the impotency of that specific petroleum lump or not is open to debate but the example exposes weaknesses in the effectiveness of petrol power by comparison to a contemporary diesel.
There is no argument then, that Diesel powered machinery has taken a floor in recent times as a promising next step for performance motoring but thats not to say it doesn’t have its flaws. Nor that old foibles of the thicker, hard burning fuel don’t linger still- even if on a less obvious level. Far from it.
Let us return to an example: the VW Group corner as represented by the FR Diesel and the excellent Golf GT TDi. The example which I will use to illustrate two issues.
Firstly, and most obviously, Diesels most basic dynamic shortcomings. Though always punchy- never more than ever in todays oil burners- they require an entirely different style of drive to extract the brutal performance they can deliver. Press on in the GT TDi and the Turbo on boost will deliver punch like few else in its segment.
Sat next to a GTi on a long pull however, you will find yourself gazing across at the established performance icon as it creeps out ahead slowly but surely. You will also note the grin on the drivers face as he approaches the upper sixes and into seven thousands on his comparatively high revving motor.
As an instrument for delivering thrills and linear performance, the petrol remains the superior mule. The diesel catches all by surprise with its impressive bursts. But like the performance it delivers, the hype is doomed to deflate.
Secondly, and less obviously but again perfectly illustrated in the GTi/GTD comparison, is the matter of manufacturer faith in its future that is either too weak to produce a product up to the petrol competition, or too strong- suggestive of paranoia about taking GTi down from its pedestal.
The Mk7 Golf GTi has been revered to no end as the default performance hatch to buy. Faithful as ever, it delivers thrills at a slightly inflated price but one that buys impeccable quality, staggering (diesel rivalling) efficiency and practicality that its forebears were always celebrated for.
Order your Mk7 with the performance pack and you get yourself a juicy 227 bhp over the standard cars 217. Meagre figures. The bit that takes a performance pack laden GTi into the upper atmospheric reaches of cornering performance is the clever e-differential at the front.
The kind of wizardry thats been about on our roads since its introduction on the Ferrari F430- the kind of wizardry my feeble mind is hard pressed to explain. If Layman will suffice- pony management to an end of dramatically reducing power understeer.
This is the kind of option would light up the driving experience of the slightly more nose heavy and thus understeer prone 180bhp GTD.
That isn’t to say, happily, that this is the end of the sporting diesel story. It’s constructive criticism of a niche that has a lot of growing to do. It’s safe to say that VAG at least, is already on the case.
The relatively quietly introduced Audi RS5 TDI-e concept demonstrates with vigour, where and how far diesel power with four r’s will go next. 380 odd horsepower and 750 nm of Torque take the e-turbocharged RS5 TDI-e from 0-62 in four flat- topping 174 mph.
Beefed up turbochargers mounted to a heavily modified and lightened 3.0 V6 deliver that punch above 3000 RPM while the electric turbine handles the action from when the pedal drops.
Real petrol rivalling performance- to hold a candle acceleratively speaking, to its stablemate RS6. The only cling on oil burning attribute remains the comparatively low rev limits but physics is a tough mistress to dictate to- especially when chasing mainstream reliability as well as performance.
Rev limits and turbo lag nowadays make for a hurdle easier than ever to jump in terms of the performance shortcomings of which are attribute- what with hybridisation technology found in the beloved three. Torque fill is the word- the miracle of the day. I see no reason why in the coming years it cant be similarly applied to give a diesel punch in areas its constituency may not cater for.
Assert for yourself others in the marketplace where diesel is coming along or indeed has been over the past few years. BMW for example will sell you the brutally effective if somewhat compromised tri-turbocharged M550D.
The thought bubble popped up for me when drawing comparison between the two Ibizas, whilst simultaneously contemplating the spec sheets of the quick Golfs. My mind is biased toward the efforts of Volkswagen group.
Whatever way you look at it, diesel has come a long way and has found itself coursing through the veins of many an exciting machine in recent years. I suspect there are only more to come.
Manufacturers need to put more research into it, have more faith in the desirability of such machines, and stop safeguarding the established petrol beasties- less bring them up to contention with the potential of their diesel contemporaries.
It should make for some juicy comparisons to come.