I’VE BEEN THINKING ABOUT engines lately – ones without turbos or superchargers. When car firms were in a technological arms race with naturally aspirated engines. Suddenly that seems a long time ago...
There are many factors to blame, but instead let’s look at why atmo engines are special and how to buy one for as little as possible.
The first part is easy: throttle response, power delivery and noise. No turbo motor offers the driver such a direct link with the engine as an atmo engine. In everyday driving the best modern ones get close, but when you really want to drive, that instant, subtle, nuanced connection is so satisfying and grants you a similarly transparent connection with the car’s chassis. You get what you ask for – nothing more, nothing less. And when you’re trying to smooth every input and make a car flow, that is such a wonderful tool. Naturally aspirated engines allow you to be a better driver. Who doesn’t want that?
They also reward your efforts. Work the engine and ’box and you feel the benefits. Okay, so the bloke in the turbo car who was once beside you might now be a few car lengths ahead... But who cares? You know the good stuff is coming and whilst he makes progress in great, loping torquey strides, you’re on an upward curve that grows in intensity and never falters.
Of course there are amazing-sounding turbo engines. But pitted against a Honda S2000 at 9000rpm, the pure howl of an M Division straight-six or a Lexus LFA V10 giving it the full F1 impression? No contest. And there’s a whole world of naturally aspirated heroes available for not a huge amount.
Four-cylinders? Honda’s K20A2 as fitted to the EP3 Civic Type R nearly hits the magic 100 horsepower-per-litre and revs to 8250rpm. That’s a lot of revolutions for about $15K! The S2000’s F20C motor is even more special. With the highest piston speed of any production car before it, this 2.0-litre screamer goes all the way to 9000rpm and produces 118.5 horsepower per litre! I’d choose the Renault F4R engines found in Clio 172s, 182s, 197s and 200s. It doesn’t rev like an iVTEC, but there’s more low-down response and I love the buzzsaw-like noise and the way it picks Clios up and hurls them into the distance.
Ultimately there’s one engine that stands above them all as the atmo bargain of the moment. You’ll find it in an E60 BMW M5. The ‘S85’ 5.0-litre V10 really is a monster. It’s a 90-degree short-stroke V10 with forged crankshaft, lightweight pistons, double-VANOS variable camshaft control, 10 individually actuated throttle bodies and engine management derived from BMW’s F1 team. Complex, thirsty and with a few reliability issues, the S85 is the ultimate representation of a time when CO2 wasn’t on our radar and big horsepower-per-litre and rpm numbers were everything to car firms. The fact you can now buy one for less than $40K is astonishing. And scary.
We’ll never see the like of the S85 again. Nor those Honda screamers, or BMW’s magnificent straight-sixes, Toyota’s high-revving 2ZZ family and even Porsche and Ferrari have gone turbocharged for all but their most extreme models.
So whether you fancy a buzzing hot hatch, a thumping family car like the B7 Audi RS4, a sonorous Boxster or a booming 350Z, now is the time to get your naturally aspirated kicks.
If you’re feeling really brave the M5 is the one, though. Just don’t come running to me if there’s an expensive bang. Spending time in the presence of greatness always comes at a cost.