Diesel - now good enough for a supercar?

E92

Look at this.

An Audi R8 with a 500 bhp V12 TDI. This is the same engine found in the upcoming Q7 V12 TDI. It averages 10.0 l/100km, whatever that is in mpg, and will go beyond 300 km/h. It also has 86 bhp more than the current R8 too.

What do ye think? Is diesel really what you need in a supercar? It ceratinly has oodles of power, but a supercar is supposed to make a glorious sound and be a high revving screamer, and there is no way a diesel can do this. I mean we all know for ordinary cars diesels are great engines, when people ask about 3 series, A6's, Avensis, Focus etc most people here will say get the diesel version if you can cause it's much quicker in the real world and you get superior economy, but I fail to see what a diesel supercar is going to achieve.

Zonda999

I always thought that the ultimate point of a supercar is to thrill you and to to get some adrenalin pumping.In a supercar with a huge diesel engine, you can think of the torque produced , it would be astronomical. So when you put your foot down the power surge is bound to be amazing. Not that the fuel consumption would be that much better than a petrol but as a technical exercise it would be pretty interesting...

unkel

E92 wrote: »

I fail to see what a diesel supercar is going to achieve.

Audi won Le Mans in a diesel the year before last. What's next? Formula 1 diesels? I wouldn't dismiss the concept of a diesel supercar just yet

E92

unkel wrote: »

Audi won Le Mans in a diesel last year. What's next? Formula 1 diesels? I wouldn't dismiss the concept of a diesel car just yet

They won it the year before too.

Lets face it, the R10 TDI has 650 bhp from a twin turbo 5.5 litre V12 engine, F1 cars in the 80s had 1500 bhp from 1.5 litre turbo petrols, and even the new detuned ones with no turbos can still give in excess of 800 bhp from 2.4 litre V8's.

Diesel will never work in F1 racing, simply because the big limitation of diesel engines is that they can only go to 5,000 rpm, and there is only so much you can do with an engine that at most can go to 5,000 rpm.

The only reason why the Audi won is because Le Mans changed the rules to allow bigger engines, Audi would never have developed a diesel LeMans car if the old restriction on engine size were still there(and in any event the FSI and TFSI engines in the R8 Le Mans car won the 24 hour race 5 times in the 7 years that car was there).

I'm sure if Audi stuck 2 turbos onto a 5.5 petrol they would outstrip that 5.5 diesel V12 TDI in their sleep for bhp, the non TFSI 1.8T if bored out to a 5.5 would give 688 bhp if you took the 225 bhp version of that engine, and if you were to go on the newer engine, using the S3's 265 bhp turbo, if you bored that out to a 5.5 you would get 729 bhp, and those engines are not built to last 24 hours, they are built to last the lifetime of a car!

unkel

E92 wrote: »

Diesel will never work in F1 racing, simply because the big limitation of diesel engines is that they can only go to 5,000 rpm

2011 plan for low revving (10k rpm) 800 BHP biodiesel F1 cars :eek:

Robbo

E92 wrote: »

They won it the year before too.

Lets face it, the R10 TDI has 650 bhp from a twin turbo 5.5 litre V12 engine, F1 cars in the 80s had 1500 bhp from 1.5 litre turbo petrols, and even the new detuned ones with no turbos can still give in excess of 800 bhp from 2.4 litre V8's.

I'm sure it could push out more HP if it (A) Didn't have to last 24 hours and (B) The air restrictors were removed.

E92 wrote:

The only reason why the Audi won is because Le Mans changed the rules to allow bigger engines, Audi would never have developed a diesel LeMans car if the old restriction on engine size were still there(and in any event the FSI and TFSI engines in the R8 Le Mans car won the 24 hour race 5 times in the 7 years that car was there).

Some would also say (Henri Pescarolo for one) that the equivalency formulae are currently biased towards the diesels which match the petrol engined LMP1 Cars for power but have to stop less often.

bazz26

Does a diesel V12 give the same sound though as a petrol V12?

Could you imagine listning to an Enzo with a diesel engine?

Biro

bazz26 wrote: »

Does a diesel V12 give the same sound though as a petrol V12?

Could you imagine listning to an Enzo with a diesel engine?

Well, I've never heard a diesel V12, but I've heard a diesel V8 and it doesn't sound near as good as a petrol V8.

E92

Ferrari and Porsche have no plans whatsoever to insert a diesel into their range.

Future Ferraris will have turbos and less cylinders in a bid to reduce emissions though, and Audi style direct injection.

They're also putting their cars on a diet, so the engines will be smaller too, and I heard some of BMW's EfficientDynamics technology will be featured in them as well.

unkel

bazz26 wrote: »

Could you imagine listning to an Enzo with a diesel engine?

The thought doesn't appeal to me

That said, what does a 10k rpm diesel sound like?

Wossack

unkel wrote: »

The thought doesn't appeal to me

That said, what does a 10k rpm diesel sound like?

iraq, I'd imagine

E92

I thought diesels due to their design characteristics could not go beyond 5,000 rpm(5,500 at the very most)?

Surely if they could there would be higher revving diesels available to buy?

if 6 cylinder BMW engines are anything to go by, the diesel won't sound even a quarter as good(and 6 cylinder petrol engines sound very like V12 petrols anyway). the real problem is that petrols can rev higher, and I'm sorry, but most petrols get better and better when they get revved(bar 4 pots).

On the other hand 4 cylinder diesels don't sound a lot worse than petrols, but I hate the sound of 4 cylinder engines anyway.

maidhc

E92 wrote: »

Surely if they could there would be higher revving diesels available to buy?

Why? At least 50% of the point of a diesel its its low revving characteristics! The gearbox can deal with the disadvantages of this just like it deals with the disadvantge of a petrol being down on torque!

Matt Simis

Biro wrote: »

Well, I've never heard a diesel V12, but I've heard a diesel V8 and it doesn't sound near as good as a petrol V8.

My V10 TDI doesnt sound like a V10 Petrol at all, it sounds different, like the noise of a low flying and low speed jet. Different doesnt mean bad. On top of that, using BioDiesel (better lubrication) gets rid of the idle chatter (will test this out myself in due time).

peasant

ahemm ...the first diesel "supercar" was built and raced in the 70's, the Mercedes Benz C111
http://en.wikipedia.org/wiki/Mercedes-Benz_C111




...I'll get me anorak ...

craichoe

E92 wrote: »

I thought diesels due to their design characteristics could not go beyond 5,000 rpm(5,500 at the very most)?

Surely if they could there would be higher revving diesels available to buy?

if 6 cylinder BMW engines are anything to go by, the diesel won't sound even a quarter as good(and 6 cylinder petrol engines sound very like V12 petrols anyway). the real problem is that petrols can rev higher, and I'm sorry, but most petrols get better and better when they get revved(bar 4 pots).

On the other hand 4 cylinder diesels don't sound a lot worse than petrols, but I hate the sound of 4 cylinder engines anyway.

AFAIK , the amount of rpm an engine can handle is down to the displacment of the engine.

For example, a Kawasaki Inline 4 249CC engine redlines at 19,500 RPM

If it was only built to last 3000 miles like a Formula 1 car i'm sure you could thrash the backside off it.

bushy...

craichoe wrote: »

AFAIK , the amount of rpm an engine can handle is down to the displacment of the engine..

It often works out that way but really its due to a couple of things ,one of the main ones is the strength of the conrods/crank since they have to put up with the piston reversing direction.

springs

bazz26 wrote: »

Does a diesel V12 give the same sound though as a petrol V12?

Could you imagine listning to an Enzo with a diesel engine?

The diesel engine that OP has talked about is this from the audi R10 LMP car.

http://www.youtube.com/watch?v=ChGGWY_CwO0

So to answer your question about sound? Not in the slightest. That diesel V12
going into the R8 certainly sounds unique. Quite as a mouse and has 1100 Nm of Torque!!!! That is absolutely crazy! It is a beauty.

Stephen

peasant wrote: »

ahemm ...the first diesel "supercar" was built and raced in the 70's, the Mercedes Benz C111
http://en.wikipedia.org/wiki/Mercedes-Benz_C111




...I'll get me anorak ...

I saw that in the MB museum in Stuttgart, I had no idea it was a diesel or that it was ever raced, just thought it was a concept car that spent its life on display.

Here's a couple of photos I took of it:




click 'em for bigger sizes at flickr.

maidhc

Stephen wrote: »

I saw that in the MB museum in Stuttgart, I had no idea it was a diesel or that it was ever raced, just thought it was a concept car that spent its life on display.

Interesting... I saw it and photographed it too, and never knew it was diesel...

JHMEG

maidhc wrote: »

Why? At least 50% of the point of a diesel its its low revving characteristics! The gearbox can deal with the disadvantages of this just like it deals with the disadvantge of a petrol being down on torque!

Indeed. The lad that developed the Honda diesel engine said there was no reason why it couldn't have vtec and a high redline. He also said there was no point, as there is little benefit: Spinning faster would release more power, but diesel is really about torque.

peasant

maidhc wrote: »

Interesting... I saw it and photographed it too, and never knew it was diesel...

slighly OT ...

The C111 actually was a sort of "test mule" for several different engines (rotary, diesel and V8) and used to set several speed and endurance records with these engines.

It was meant to go into production for general sale, but that was cancelled (due to the first "oil crisis" , I think)

Henry Ford III

I was fortunate enough to attend Le Mans in 2007.

The 1st 2 cars were both diesels. An Audi follwed by a Peugeot. Another Audi crashed during the night.

The noise of the racing diesels is very different from high revving n/a petrol engines. It's a lot quieter for starters, and the whistle of the turbos can be heard well before the car passes you. The acceleration looks effortless.

The best sounding cars were the Aston Martin V12's, and the Panoz and Corvette V8's. They rocked. The noise when the Aston changed gear was like somone firing a shotgun.

The V10's wailed.