Blog: Glenn BrooksLow CO2 gives you wings

Glenn Brooks | 5 December 2011

Drag-lowering, Renault says

Drag-lowering, Renault says

Back on 15 September, I blogged about some mysterious pieces of plastic I spotted attached to the sides of the new Civic diesel. Today I noticed aero add-ons in a similar place on a low-emissions Renault. So what do we think: function or fashion?

Here's a shot of the rear of the Clio Expression Eco dCi 88 which I drove at a Renault event this afternoon. The car has an admirably low CO2 average of 94g/km, something which was once fairly amazing but is now becoming commonplace in the supermini class. And if you're wondering about the 88, it's horsepower (DIN).

But back to my cameraphone-snapped pic. I asked Jeremy Townsend, Renault UK's well-informed director of Communications why each side of this Clio's rear window spoiler has a pronounced bump emerging from it. He maintains that these tiny aero addenda play a small role in lowering wind resistance, confirming that only the Eco dCi 88 variant has them. Sceptical? I was too. So let's look at some facts: thanks to various modifications, the European Commission's test rates the Eco at 78.4mpg on its EC Combined cycle versus 70.6mpg for the standard (106g/km) dCi 88 Clio.

Well, it does then seem as though both Honda and Renault's wind tunnels have found the same way to get the tiniest improvement on an already super-low CO2 number. If you're still sceptical, consider this, which is what I have done: ask yourself why a manufacturer would go to the trouble of adding those little winglets? I have concluded that they're a tweak, and that they probably do work.

Speaking of the quest for a top-notch CO2 number, I've been driving a new and small-engined version of a large-ish car over the course of the last week, courtesy of Vauxhall. Will publish my thoughts on the '2012' 1.4-litre Insignia in a few days' time. But in short, this heavy estate is a really good car that's been saddled with too tiny an engine and gear ratios that are too long. The blame lies not with Opel's engineers but with the CO2-based taxation system which exists in so many European markets. And with the first Euro 6-compliant models already with us, are we about to see a steady roll-out of otherwise good cars troubled by too-small engines?


BLOG

Colossal China powers on

I'm starting to get a small idea of the scale of things here in China, but really, I'm only scratching the surface of this vast country....

BLOG

China Hot Pot

Given the startling complexity of obtaining a journalist visa for China - the code 'J2' is now indelibly stamped on my mind - it was with some surprise how swiftly I managed to sail through airport im...



Forgot your password?