17 Dec 2012

Why four wheel drive is brilliant

Matt Hubbard disagrees with the 'purists' who say rear wheel drive is the only way to achieve the closest bond between car and driver 

The purists say rear wheel drive is the only way to transmit power from the engine to the road.  John Cooper said the engine must be behind the driver too, but that's another story.

The purists say that only rear wheel drive delivers the true driving experience.  The purists say that front wheel drive is rubbish because the front wheels have to do the work of steering as well as pulling the car forwards.  The purists say four wheel drive is rubbish because it naturally induces understeer.

I say bollocks to that.

Let's get front wheel drive out of the way.  It can be the best option but, in my opinion, only in small hatchbacks.  For packaging, as well as dynamic purposes, a VW Polo or Vauxhall Corsa is best suited to front wheel drive. FWD really only suits cars with a wheelbase shorter than that of a VW Golf or Ford Focus - and with limited horsepower.  Hit 200bhp and a front wheel drive Golf or Focus becomes an understeering monster that only electronic trickery (more of which later) can reign in.  That's why the Golf R32 has 4WD and the Ford Focus ST is a lairy, torque-steering handful.  With 4WD it would be twice the car it is already.

The Ford Mondeo has long been lauded as a great handling car, which it is.  But front wheel drive does not suit the Mondeo's chassis.  The wheelbase is such that, with the front wheels pulling the car along, a whole heap of potential fun, and driving dynamics, is lost.  The Mondeo would suit rear wheel drive up to 200bhp and four wheel drive above it.

Onto rear wheel drive.  The Mazda MX5 absolutely suits RWD because it's a small sports car with limited engine power.  As such the experience is all about balance and handling, rather than outright power.  This is why the VW Scirocco is not applauded for it's dynamics whereas the MX5 is.  The Porsche Boxster has it just right too.  206bhp is perfect for it's rear engined configuration.  The 265bhp in the Boxster S is sprightly but often lairy.  BMWs 260bhp 330d delivers it's power to the rear wheels mainly via torque rather than outright bhp and is pretty much the upper limit of a safe handling, all weather RWD car.  The 335i is a kerb away from a hedge visit.

But in some cars too much power can engulf the driven (rear) wheels and the driver has to rely on DSC, traction control and all manner of electronics to tame the subsequent over delivery of bhp's.  This single area, for me, takes away from the driving experience of such cars.

Two examples.  Mercedes' SLS AMG and Jaguar's XKR.  Both big, rear wheel drive cars with over 500bhp on tap.  In both cars the back end will step out, even when driving in a straight line, if the accelerator is pressed suddenly.  The electronics then sort things out and bring the car back into line.  Where's the driver input in that?  Put too much power down when cornering and the back end slides a little then chirrups and is dutifully towed back into line by the DSC and TCS.  Boring!

Sure, you can turn the traction control off but then both cars become massive oversteering handfuls.  Fun on track but not so much on a wet Swindon ring road or the back streets of Barnsley with the kerb inches from those expensive 20 inch alloys.

That's the point.  Massively powerful cars with rear wheel drive are only viable because electronics take over from driver control, which can make the driver feel heroic but in actuality take away from the experience.

30% of all Audi's sold in the UK are in Quattro guise.  You can buy a front wheel drive Audi A6, which is silly because the wheelbase is even longer than a Mondeo's.  The only sensible option is to get it with four wheel drive.

Why?  Because 4WD allows the driver, not the electronics, to deploy 500bhp to the road and to control it using only the steering and pedals.  I drove 200 miles today along a mostly wet A303 and 40 miles of unlit, absolutely soaking back roads in my Audi S4.  I was able to fully utilise the S4's 340bhp without the need for traction control because I knew that when I put my foot flat to the floor whilst coming off a roundabout the power would be distributed evenly and the car would shoot forwards without any hint of over or understeer.  Not with the front end washing towards the barrier as it would in a FWD, or the back end catapulting into the barrier as it would in a RWD.  The suspension and Torsen differentials in the Audi mechanically control where the power delivery goes and I control how much power is inputted - all of it if I want.

I could charge along the back roads safe in the knowledge my family wouldn't have to create a makeshift shrine at the tree I would surely have killed myself against had I pushed 340bhp so aggressively through the back wheels.

The Mercedes C 63 AMG is a fantastic car to drive.  But you can only get the most out of it on track.  On the road it would be much better served with Mercedes 4-Matic four wheel drive.  500bhp is wasted when only driven through the rear wheels.  Talk of controlling oversteer is absolute rubbish.  A tiny bit of oversteer is fun. Any more than that will result in hospitalisation.

It's so frustrating that car manufacturers such as BMW and Mercedes only put four wheel drive in their SUVs.  Sure, poseurs can have their rear wheel drive SLS AMG but I'd much rather have the neutral, planted handling of a 4WD version.  It's wonderful that Ferrari have already put 4WD drive in the FF and it's fantastic that Maserati are talking about 4WD cars.  Lamborghini have it spot on with their 4WD and Jaguar disappoint with their decision to make 4WD available to most markets - but not the UK.  Surely it's needed here the most with our awful roads and constant rain.

Porsche have the right attitude.  RWD for motoring journalists and people who don't leave the confines of the M25 or M60, and 4WD for those of us who don't want to die.

To summarise.  FWD, RWD and 4WD are all equally valid, in the right circumstances.  To my mind the very broad rules are:

FWD - small hatchbacks and mid-sized hatchbacks of up to 200bhp
RWD - all small sportscars, all saloons, estates and sportcars up to 300bhp (the line between 200bhp and 300bhp is the RWD/4WD changeover)
4WD - all SUVs (take note Evoque) and anything over 300bhp

So that's my argument.  Do you agree, or disagree?