With an engine as special as the RS4’s 4.2-litre V8, it’s a bit worrying when it seems to be gaining an appetite for oil. Two and a half litres in 7000 miles isn’t gluttonous, but this ‘Long Life’ stuff costs about £17 a litre, and sometimes an appetite grows… Mind, the handbook says half a litre every 1000 miles isn’t a worry, and also that oil consumption can be expected to be higher in the first 3000 miles.

Since the Audi came back from its Le Mans trip (gleaming – thanks, Chee!) I’ve only done about 1000 miles, but I’ve checked the dipstick twice. Driving the family sedately up to Cleethorpes for my niece Jess’s 18th birthday bash, I noticed the oil temperature (a permanent fixture on the dash display) sitting at 102 degrees C. Having not seen it in three figures at a cruise before, I stopped at the next services to check the level. It was fine.

Five hundred miles later, out of curiosity, I checked it again. It doesn’t appear to be going down but I think I’ll play safe and book it in for its first service now, rather than waiting until 18,000 miles, which is feasible with the ‘Long Life’ oil. Such a high mileage does seem a remarkable stretch for a near 100bhp-per-litre engine that revs to a heady 8000rpm – a speed beyond which engineers say internal wear accelerates markedly.

I drove an RS4 with a different exhaust recently. Milltek has devised its own cats-back system, which has oval tailpipes and thus looks very similar to the original equipment. But, by heck, it sounds different. From start-up the standard, valved system gives a deep, resonant burble, but the valve closes at 1500rpm and the V8 then remains pretty quiet until about 5500rpm, at which point it really goes for it. The Milltek system is unvalved and of fractionally bigger bore diameter, and it gives the V8 a much stronger voice, from tickover to limiter. Blip it and it sounds like a big, angry American V8 rather than a demure, sophisticated German.

According to Milltek boss Phil Millington, the system, which costs £1050, is good for an additional 20bhp and about 16lb ft, but he says that the main aim was to enhance the driving experience. The fuller, richer noise at low speeds will certainly turn more heads in town, and it makes the engine feel more eager elsewhere. I’d be very tempted, but even on a light throttle the system is loud and proud, and I don’t think it would be comfortable for the kids. However, Milltek is currently working on a valved system of its own – now that sounds like music to my ears. For more info visit www.millteksport.com