Audi RS5 diesel driven

30 May, 2014 4:30pm David Vivian

Clever electric turbo gives Audi’s first-ever RS-badged diesel petrol-like responses

Audi has given Auto Express a tantalising glimpse of what might, in the near future, become the basis for a range of high-performance turbodiesels aimed squarely at driving enthusiasts. And the 380bhp, 174mph RS5 TDI-e Concept previews what could be the 
first diesel Audi to wear an RS badge.

Under the bonnet is a heavily boosted version of the next-generation 3.0-litre V6 TDI biturbo, complete with ‘e-booster’ technology that contributes towards the thumping 750Nm of torque, developed from just 1,250rpm.

With a claimed 0-62mph time of four seconds and a 174mph top speed, the performance certainly seems worthy of RS status. The purpose of ‘e-boost’, a small electrically driven blower plumbed in between the intercooler and the induction system, is two-fold.

Even diesel engines with two-stage turbos – the smaller turbo spinning up more rapidly to generate boost at lower revs and smaller throttle openings before the larger unit shoulders the workload – can suffer from a momentary dead spot when pulling away from rest due to the mass inertia of the turbocharger impeller.

The electric turbo gets this spinning rapidly before the hot exhaust gases can do the job effectively, giving more immediate throttle response away from rest and eliminating off-boost lethargy when you get back on the throttle at, say, the exit of a bend.

Audi RS5 diesel rear static

The system operates up to 3,000rpm, at which point it’s no longer needed and bypassed completely.You might think a diesel ‘RS5’ would struggle to live with a 552bhp RS6 Avant pace car being pushed hard by a pro driver around the twisty 2.1-mile Audi centre handling circuit. Think again.

The striking thing is how easy it was. The deep bass of the exhaust note may be artificially enhanced, and sounds more V8 than V6, but it’s entirely in keeping with the effortless way the RS5 TDI-e piles on speed, riding a seemingly endless wave of torque that punches the car out of slow bends with a ferocity not even the RS6 can match.

Although peak power is developed at a modest 4,200rpm, all of the engine’s prodigious torque is available from just over tickover and Audi’s superb eight-speed auto box keeps the action flowing.

Twenty five years after producing its first diesel, Audi’s commitment to the future of this engine tech is obvious.

The RS5 V6 TDI-e proves that diesel is a viable alternative to petrol power for the sportiest Audis and that ‘e-booster’ electric turbo tech brings significant gains in throttle response and driveability. We’re looking forward to the first production diesel RS, which could arrive as soon as next year.

Disqus - noscript

I'm a recent convert to powerful diesel engines. I've been driving a 330d since March and find the effortless, relentless acceleration completely addictive and when I really hammer it I can still get at least 30mpg.

Yeah the bmw 335d is the king of the diesels at the moment it's ludicrously fast! 340d or 345d

The Audi a8 4.2 tdi with 385bhp is also worth mentioning.

Alpina D3

I cannot understand who this is aimed at? How many people, who would ever want a car like an RS Audi, would actually be put off by it having a petrol motor?

I get it as a concept, as an engineering exercise for bragging rights it's fine, but as a consumer product it's...unnecessary. Only a tractor needs so much torque at so few revs, unless Audi see this as destined to tow jumbo jets around at 5 mph?

Of course, if they do put it into production, they’ll no doubt flood the market with this version, strangle the supply of petrol-engine models, and then quietly lay the petrol to rest, citing poor sales and lack of market desire. This is precisely what is happening (arguably has happened) with manual gearboxes.

Stop moaning!

I've realised that once you make the jump to Diesel you won't go back to petrol! I'm hoping that my next car will be a BMW 335d or a 635d

Audi Q7 6.0 v12 TDI!

More torque and the undeveloped Quattro system will only result in more torque steer. And the RS5 suffers badly from it currently.

when it comes out, drive one and you'll understand. In the mean time drive a BMW 330d.

A super high revving petrol car like a S2000 is great fun on special occasions but can be quite tiring to get the most out of it on a daily basis. Also when you do go up to the rev limiter (which you need to if you wanna have fun), you'll be lucky to get 10mpg!

Not nearly as good as a 330d. I tried both, but the X-drive in the 335d spoils the handling and steering.

Haha, so many diesel loving people around. Try getting into a car with a V8 PETROL engine and diesel's will be a thing of the past.

Diesel's have too many dpf problems and sound like a tractor. Theres a reason Ferrari's are petrol. They'd laugh at you if you mentioned diesel to them!

All I see is problems down the road. No one want's a second hand Audi to begin with due to maintenance cost, so can you imagine what value a diesel used on is going to have and the maintenance issues? I have a diesel shop van and I never want to see another diesel as long as I live. Also I agree with Morg, if you can buy a A6, the petrol aint gonna matter.

Yeah it twice the engine size it's a pointless engine you'd be better off with a petrol v8. Why would you have a noisy diesel if the speed and mpg and price tag is worse than the cheaper petrol madness. Whereas I'm saying the 335d takes some beating on these factors!

Yeah I agree a better car the 330d cheaper better mpg nearly as fast better rwd handling but still power for your money the 335d is top of the league! If they bring out a 340d or 345d it will be a diesel super car with 50mpg.

I'd like to see a faster car 0 to 155mph with over 50mpg combined cycle cheaper than 50grand nothing can touch it many come close but none can beat it. All round package is unbeatable. Having your cake and eating it.

For a 4 pot yeah at the top but not quite king of diesels. Great car though always liked the discreet look of the d3.

D3 is a Six now.... have a look ;)
Acceleration 0-100km/h (s) 4.6
Top speed (mph (kph)) 173 (278)
Emissions 139g/km and 55+ mpg!!

The 335d

a desirable diesel!

Yeah same engine as 335d so gives us the same result but is it as good a package? Less warranty mmm. That's like taking the best engine and then tweaking it and claiming victory it still started with what I'm saying the 3l bmw diesel and for its size will take some beating. Of course if u tweaked the 335d it would be faster again but as a base engine breath taking. Has it got 4wd?

There are still far to many people who think Audi's are reliable - lol. I personally hate them as they are over priced seats and not proper premium brand in my eyes where as BMW and Merc are. Plus I can almost guarantee that the electric turbo will fail just outside of the warranty period and cost ££££ to replace.

More power than a 335d (313 vs 350) and RWD!

NO MORE AUDIS, PLEASE!!!!!

I'd have the genuine bmw with a remapped ecu easily 350 bhp if not more and I think I'd have 4wd when your pushing 800nm and 350bhp

**Yes bring it on I Love Fast Twin Turbo Diesel's New BMW 330d M sport What a Car Addictive & The Handling.

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