The engine - Technical discussion

[Erik]

The ultra-compact V8

Clear facts and figures prove the impressive potential of this outstanding eight-cylinder: maximum output of the 4.2-litre power unit is 420 bhp. Peak torque is 430 Newton-metres at 5500 rpm. And no less than 90 per cent of this maximum torque is maintained consistently throughout a wide range of engine speed from 2250 all the way to 7600 rpm.

The V8 power unit is ultra-compact in its dimensions, fitting snugly into the engine compartment of the RS 4 without requiring any changes to the body of the car. The camshafts and ancillary units, with the exception of the alternator, are all driven by a chain for easy maintenance. An all-new development, the eight-cylinder powering the RS 4 comes, inter alia, with modified pistons and connecting rods, as well as a new crankshaft together with its bearings and new cylinder heads. A double-chamber exhaust system with extra-large pipe cross-sections helps to boost engine output and performance to an even higher level, these significant improvements all adding up at the end of the day to give this 4163 cc power machine an output per litre beyond the magical 100 bhp limit.


http://www.rs6.com/pics/RS4/RS4-2005-1001.jpghttp://www.rs6.com/pics/RS4/RS4-2005-1002.jpg

http://www.rs6.com/pics/RS4/RS4-2005-1003.jpg

[Erik]

Here's the technical data. For the EU-version.

Sorry if the text comes out a bit weird. :looking:

Programme for Germany – Status: February 2005

Model Audi RS 4 Saloon

Engine / electrics

Engine type: V8 spark-ignition engine, four-valve technology, two light-alloy cylinder heads both with double overhead camshafts (DOHC), two inlet valves, two sodium-cooled exhaust valves, intake manifold with integrated charge movement
Valve gear / number of valves per cylinder Cam followers with hydraulic valve-play compensation / 4
Displacement in cc / bore x stroke in mm / compression: 4163 / 84.5 X 92.8 / 12.5 : 1
Maximum power output in kW (bhp) / at rpm 309 (420) / 7800
Maximum torque in Nm / at rpm 430 / 5500
Engine management / mixture preparation
Fully electronic petrol direct injection with air-mass measurement, mapped ignition with solid-state high-voltage distribution, continuous camshaft adjustment for the intake and exhaust valves, Bosch MED 9.1 coordinated torque control
Exhaust emission control Two tubular manifolds, two primary catalytic converters, two underfloor main catalytic converters, cylinder-bank selective lambda control with permanent lambda control
Emission category EU4
Alternator in A / battery in A/Ah 190 / 520/110

Drive / transmission

Type of drive
Permanent quattro four-wheel drive, automatic locking Torsen entre differential, electronic differential lock EDL on all driven wheels using brake application principle, ESP

Clutch Hydraulically operated single-plate dry clutch with asbestos-free and lead-free linings, dual-mass flywheel
Gearbox type 6-speed manual gearbox, synchromesh on all gears
Gear ratio in 1st gear / 2nd gear 3.667 / 2.211
Gear ratio in 3rd gear / 4th gear 1.520 / 1.133
Gear ratio in 5th gear 0.919 / 0.778
Reverse gear / final drive ratio 3.333 / 4.111
Running gear / steering / brakes
Front suspension Independent four-link front suspension with virtual steering axis,
anti-roll bar: single-tube shock absorbers and coil springs, radius link
Rear suspension Double-wishbone rear suspension, anti-roll bar
Steering / steering ratio / turning circle in m (D102) Maintenance-free rack-and-pinion steering with power assistance / 13.10 / 11.10
Brake system, front/rear Dual-circuit brake system with diagonal split, anti-lock brake system ABS, brake servo, electronic brake force distribution EBD, ventilated and perforated brake discs at front and rear, front: eight-piston high-performance brakes

Wheels/tyres 8.5 J x 18 alloy wheels in 5-arm design / 255/40 R18

Performance / consumption / acoustics
Maximum speed in km/h 250 (governed)
Acceleration 0-100 / 0-200 km/h in sec 4,8 / 16,6
Fuel grade Unleaded Super Plus, 98 RON (95 RON with slight reduction in performance)
Fuel consumption: urban/extra urban/overall, l/100 km 19.7 / 10.1 / 13.7
CO2 mass emission, g/km 329
Standing / drive-past exterior noise level in dB (A) 92 / 75
Servicing / warranty (Germany)
Long-life service after a maximum of ... km According to service indicator up to 30,000 (max. 2 years) 1)
Vehicle / paint / rust penetration warranty 2 years with unlimited mileage / 3 years / 12 years
Insurance classification in Germany Data was not available at the time of printing
Weights / loads
Unladen weight in kg / gross weight limit in kg 1650 / 2260
Axle load limit at front / rear in kg 1250 / 1150
Roof load limit in kg 75

Capacities

Cooling system capacity (incl. heating) in litres 11.5
Engine oil capacity (incl. filter) in litres 8
Fuel tank capacity in litres 63

Body / dimensions

Body type Fully galvanised, unitary steel body, crumple zones at front and rear
Number of doors / seats 4 / 5 with additional side protection, 5 seats
Drag coefficient cD / frontal area A in m2 0.31 / 2.17
Length (L103)/ width excl. mirrors (W103)/ height (H100), mm 4589 / 1816 / 1415
Wheelbase (L101) / track at front/rear (W101/W102), mm 2648 / 1559 / 1569
Height of loading lip in mm (H195) 682
Luggage capacity in l, acc. to VDA block method (V210) 460 (with rear seat folded down: 720)

[tailpipe]

Erik,

I think your post elsewhere on the forum that a sub-8 minute lap time of the ring may be possible is born out by this data.

Everyone I spoke to Audi about the RS4 tells me that the M5 was the benchmark, not the M3. Audi wants to achieve with a V-8 what BMW needed 10 cylinders to do. There is a lot of R8 race technology in this engine.

The anticipation is almost too much. I cannot wait to drive mine.

[Hawk]

1650 kg the weight? distribution in %?

[5000S old skool]

only four valves per cylinder? what happened to five?

[clam]

Originally posted by 5000S old skool
only four valves per cylinder? what happened to five?

Can't be combined with FSi, b/c the injectors need the space in the cyclinderhead.

5v technology has proven to have no particular benefit, anyway. F1 has done away with it a long time ago, and the new road Ferraris are also back to 4v.
The practice didn't back up the theory. The small breathing benefit didn't hold up to the drawbacks: complexcity, more moving parts (that the engine has to move), variable valve systems were limited (I guess),... in the real world, there was no performance enhancement.
Apart from boasting rights, off course. ;)

[5000S old skool]

Oh yeah, thats right, the 3rd intake valve doesnt reallly need to be there anyway scince the injector is right there.

[gjg]

Fuel consumption: urban/extra urban/overall, l/100 km 19.7 / 10.1 / 13.7

Fuel tank capacity in litres 63

this will be a major drawback at least in Europe - that tank in Germany on a good day will be good for less than one hour. Worse than RS6 ....

[Eckoman]

Originally posted by gjg
this will be a major drawback at least in Europe - that tank in Germany on a good day will be good for less than one hour. Worse than RS6 ....
One hour?! think about that again. If your fuel tank of 63l would only last for one hour, you must be travelling at ~300km/h constantly while burning about 20l/100km. I dont think so.

[Benman]

Originally posted by gjg
this will be a major drawback at least in Europe - that tank in Germany on a good day will be good for less than one hour. Worse than RS6 ....
Doesn't 63L translate to @16.5 gallons? if so then yes, this would be a vehicle with an inferior driving range to the Beast (which by the way I've had several trips last me OVER 400 miles).

Ben:addict:

[Nordschleife]

Originally posted by Eckoman
One hour?! think about that again. If your fuel tank of 63l would only last for one hour, you must be travelling at ~300km/h constantly while burning about 20l/100km. I dont think so.

While going for it, I would expect around 24 litres per 100 kilometres. Which would equate to a tank per hour, like a tuned RS6 when running at 300.

R+C

[Eckoman]

Originally posted by Nordschleife
While going for it, I would expect around 24 litres per 100 kilometres. Which would equate to a tank per hour, like a tuned RS6 when running at 300.

R+C
With 24l/100km you would still need to be travelling at 262,5 km/h constantly for one hour, which is hard to achieve, even impossible with the stock RS4 since it is limited to 250km/h.

So the tank should last well over an hour.

[Benman]

Originally posted by Eckoman
With 24l/100km you would still need to be travelling at 262,5 km/h constantly for one hour, which is hard to achieve, even impossible with the stock RS4 since it is limited to 250km/h.

So the tank should last well over an hour.
The limiter is leanient as I've seen first hand so it's possible to do 262KPH+. As for maintaining those speeds, maybe they're thinking of renting Nardo or something:hihi:

Ben:addict:

[Nordschleife]

Originally posted by Eckoman
With 24l/100km you would still need to be travelling at 262,5 km/h constantly for one hour, which is hard to achieve, even impossible with the stock RS4 since it is limited to 250km/h.

So the tank should last well over an hour.

Eckoman

You obviously have not driven a stock RS4; its speed limiter does nor cut in until about 270 kph. Most people in Germany who drive this sort of car have the speed limiter removed.

If you are running at over 300kph, with a few slow downs for traffic and hard acceleration back to speed, in practice the tank will not last more than an hour.

For me, driving in Germany, the biggest single factor when making fast trips is the time spent refuelling. There is a famous story from Australia where a Porsche 996 Turbo was driven from Darwin to Alice Springs. At the same time as the Porsche left Darwin, a Toyota Landcruiser with a family of four on board also headed south. At the end of the trip, the Landcruiser got there first because it did not waste so much time refuelling.

Driving from Berlin to Munich takes between 2 1/2 and 3 hours depending on duration of fuel stops, if done early in the morning or late at night. Without a bigger fuel tank I really cannot get it any less.

That is about 580 km with all but 6 or 7 km on the Autobahn. Starting with a full tank I need to stop twice for gas, whether I am in a Porsche Turbo or an RS6 or an RS4, nor does the size of the tank make any difference, it seems the bigger tanks go into the cars which burn more gas!

R+C

[gjg]

Originally posted by Benman
(which by the way I've had several trips last me OVER 400 miles).

Ben, 400 km/tank in my case is a good fuel mileage ..... :wo:

and


As for maintaining those speeds, maybe they're thinking of renting Nardo or something


nope, depending when and where you can do that on the bahn :thumb:

[gjg]

Originally posted by Eckoman


With 24l/100km you would still need to be travelling at 262,5 km/h constantly for one hour, which is hard to achieve, even impossible with the stock RS4 since it is limited to 250km/h.

So the tank should last well over an hour.

you would hardly have one hour of ideal constant speed on the aiutobahn. SO I stand to my one hour or less estimate........:argue:

RS4 (or RS6) Avant with 100l fuel tank would be a nice A to B transporation ....

[tailpipe]

Hello Nordschliefe,

You have been conspicuous by your absence from the boards. Welcome back! I'm very keen to hear your perspectives on the new RS4 and how you think it will handle versus competitors.

Will it lap the Ring in under 8 minutes? And will it give the the new M5 a run for its mone,y not to mention the M3 CSL?

[Nordschleife]

Hi

I've been away in SE Asia since the Tsunami and only recently back.

Decided to give Geneva a miss this year in favour of IAA at Frankfurt in September. As this is the home fixture for the German manufacturers and it only occurs every other year, expect some fun cars.

The new RS4 engine is very impressive, I expect to see it in the Le Mans Quattro. The rest of the car leaves me completely underwhelmed.

Face it, the V8 S4 is as boring a car as Audi has ever made, and what has the new RS4 got to offer - a deformed steering wheel and a redundent starter button (yes, redundent, as far as I can tell you still need the key). The rotors look to be much better, but the 8 pot callipers are lacking in swept pad area.

Times at the 'Ring, well its under snow right now and several stretches cannot be used until they have been resurfaced, and given the current weather, who knows when that will be; so times are a little problematic.

Undoubtedly with MPSC or PC tyres and the right driver it is going to be quick round the 'ring. On a fine day I expect the M5 and M3CSL to eat its lunch, a wet winter's night in the Alps is another matter however.

I'm sure lots of people who are new to RS cars will love it. For me the creators of this car have largely forgotten that 'less is more'. It is very confused and sends out mixed signals.

R+C

[tailpipe]

R,

I agree that the starter button is a bit pointless and the steering wheel is merely a gimmick, but you're being a little hard, aren't you? The new Quattro system with revised torque split plus suspension tweaks should surely improve ride and handling? And they have reduced the weight by about 200 lbs?

Hopefully the engine alone makes this car a worthwhile addition to the range. I find the B8 A4 Avant very practical, (from a family transport point of view); so the RS4 Avant really should offer the best of all worlds.