Maybe you should do that. Taking out the race cars with sanctioning rules that prohibit AWD, you'll find a lot of AWD Porsches and Lambos in the top 30.

Look here for more info...

 

Mmm , the fastest 4WD car I could find was in position 26 at the Ring. And a lot of the racing formulae allow 4WD these days.

 

thanks MaM

I don't know where you came up with the S2000 comparison and your right I have never driven one so I can not say yeah or nay???? this thread was turned by you stating that n/a is faster throttle response then a S/C engine and I respectfully disagree regardless of how many FI magazines you are reading. If you want to compare the throttle response of an F1 car to a S/C E55 or a specific car like a S2000 then maybe your right in those specific examples.
I have raced shifter 125mph go carts, flat tracked open class motorcycles, drag raced low 10 second street bikes and low 11 second street cars, have owned S/C off shore boats and more but all the stuff I have ever been around has S/C more efficient with faster throttle response compared to N/A but maybe my position is not the only position to support and I am ok with that.

 

Well my argument has always been about a high compression NA engine in a good high of tune, preferably with ITB's. Maybe it's a misunderstanding on my part. I was not talking about your typical pushrod engine from the 70's. Sure compared to that, a modern SC car might well have better TR.

But I'm talking about the new E63 engine. Have you seen the spec sheet? And have you driven a C32 & C55. In your opinion, did one feel more responsive than the other?

 

Interesting thread. Some valid comments, interesting technical exchange, and a few extremists on both sides.

I feel that one of the reasons Mercedes resorted to supercharging was to catch up to the performance of the BMW M-cars. BMW was way ahead of AMG from a performance standpoint, and supercharging/turbocharging existing engines was a quick way to eradicate the disparity. Now that AMG & BMW/M have relative parity it makes sense (to me, at least) that AMG is now developing engines "from scratch", that don't need to rely on supercharging to have fantastic specific output.

Others may feel differently (and should spend their $$$ accordingly), but I will always choose a well-designed NA engine over a boosted one (when given a choice). I find them far more enjoyable and rewarding to drive; kind of like comparing a scalpel to a Bowie knife. However, it's important for each owner to choose the appropriate tool for his own likes or dislikes. Neither approach is inherently "wrong", I just like the normally aspirated approach better, and find it to be a more elegant solution from an engineering standpoint.

If you look at certain high-end manufacturers -- take Ferrari, for example -- there is almost NO history of boosted engines (in road-going cars). The 288 GTO comes to mind, but that was a very limited production vehicle that proves the exception. Look at what BMW was able to achieve with the normally-aspirated engine in the McLaren F1...

 

my carts, bikes, boats, and most of my cars are not old 70 push rod engines, although I do have some old big block stuff in my stable.
I have not driven a C55 or a C32 but I have driven the two different Audi S8's I had, my E420 before and after S/C addition, and obviously I have not driven the E63 so again we are not tracking and that's ok.
I have had numerous N/A injected V-8's some before and after a S/C and in every case the S/C was more responsive from idle on compared to N/A, again JMHO.

 

OK, fair enough. But I drove a C55 & a C32. Hope I don't get flamed for this by the C32 owners, but I feel the C55 is a far superior car. ANd its not just the better handling & engine note. It felt more responsive. If felt like it pulled better at high rpm. It didn't feel ashmatic at high rpm like the 32 did (once again no offence). It felt like it pulled better at low rpm as well. Had a mountain of torque just off idle.

The cars you had & s/c'd may well have had better response post S/C though. I don't doubt you there.

 

Are you looking at the same list I posted? I see at least 5 AWD cars in the top 15.

For a good example of what I mean, look back to when an AWD car was entered for the FIRST time in a racing series. AWD completely dominates until the RWD guys complain and then the sanctioning body adds weight or other restricitons. Do you remember the IMSA/SCCA TransAm and GTP series of the 80's? Audi came out with their AWD cars and smoked the field 1-2 every race until they had 400 pounds of extra weight added MID-SEASON! They still won the championship that year.

 

I agree with you here. The stock C55 does pull better than the stock C32. However, the modified C32 (ECU, pulley, etc) I drove earlier this year was so damn fast, it was scary.

 

I just pray for the cash flow to not give an F....then I am gonna slap on a monster Kleemann blower ON TOP of the awesome 6.3.

Now wait a sec....would you (money not object) go blower or twin turbs??

 

there is noway in hell my 55's response is as fast as my Z4, my old M3, or even my old old a4 2.8

 

Sorry bout being lazy, this may have already been mentioned.

Supercharger on 55 engages at a determined point.

What people perceive as throttle response is usually in the first few thousand rpm and a motors ability to respond in that period.

If I am not mistaken, when you punch the 55 in the garage....for the first few millisecs, she is an N/A no?

Maybe I am off in that when punched, blower engages automatically.

Anyone know when blower actually engages?

The new 6.3's vertical intake ducts look f'in fierce....I would have to put the bucks on that having some niiiiceee throttle response.

 

Money not being a problem, TT without a doubt. More power to be made at the upper RPMS where there is less parasitic loss compared to the SC. Just wait for MB to do it for you

 

If I understand what you're saying, perhaps I can rephrase it:
The NA throttle response is more linear and direct, while the SC throttle response is more "all or none" .
It is true, comparing my SL 55 to my E39 M5, that you can't quite feather the throttle with the SL as you could with the M5. However, the lag time in the SL was very small (fraction of a second). In fact, it was so small that unless you were the driver, you couldn't tell thhat there was a lag

 

Anyone think that mbz (amg of course) is going n/a as a marketing tool in addition to the other variables mentioned?

Release a new and improved n/a engine .. then 1-2 years down the line turbo it .. it's like two new releases on the same engine ..

If you're putting $$ into R&D for a new engine why not get two "new" sales cycles out of it?

Just a thought .. they did it before with the S55 ...

 

Ok this has been discussed the world over, on forums all the planet many times. Do a Goole search for "Quattro the unfair advantage". I was an avid fan of the BTCC at the time & followed all the races.

The racing AWD systems used by Audi were not representative of the production Quattro AWD system, and that's why it was considered an "unfair advantage". It was a prototypical AWD system that did away with the Torsen differential due to some strange sideways "walking" that Torsen introduces under certain drift conditions. On the quattro list this was labeled the "spider bite" and hotly debated for years. QUATTRO WAS BANNED BECAUSE Audi raced a Viscous Coupling (VC) "quattro", not available anywhere else. Quattro that was outlawed was a VC awd A4, not a Torsen A4. Audi was claiming that awd, all awd they use, as quattro.

- IN the BTCC Audi got banned for having an unfair advantage with Quattro in 1997. However, all the cars in the BTCC in 1997 were FWD. So, the fact that Audi got banned for beating FWD cars in the BTCC is irrelevant when comparing AWD to RWD. Just a point.

- Tyre wear is an important factor in Touring car races. A 4WD car will have less tyre wear than a 2WD, especially a powerful 2WD with relatively narrow tyres (as the Touring car rules were)

- The Touring cars all weighed around 975kg with the same power. Audi had to carry 90kg extra in their second season which was droped later (BTW they lost the 2nd year). However, the drivetrain are more efficient that a road (what with straight cut gearboxes, etc). SO the drivetrain loss wasn't as much. On a road car you would lose 15% more power to the wheels & then have to carry over 200kg more weight than your 2WD counterpart.

- Some of the forumlae had 2.0 turbo's. SO the torque would hit when the turbos came on boost. Coming out o the ends Quattro would have the advantage putting the power down & accelerative tyre wear spread over 4 tyres. But the minimal disadvantages of 4WD in the racing application of weight & losses were not enough to outweigh the advantages.

- Audi bought the best drivers (I remember a quote that Frank Biela could win driving a Yugo)

- Audi had the commitment of Dunlop for tyre development.

- The A4 BTCC chassis had one of the BEST front suspensions around. A racing suspension can do wonders to cure 4WD or 2WD understeer.

- There is very little correlation between super touring and the cars which we can purchase. Here's a comparison of quattro in road cars, same driver, same track, same day:

Car Lap time average
TT fwd 180hp 1.04.52
TTQ 180hp 1.06.23
TTQ 225hp 1.05.14
A4 1.8 T 1.08.39

Bear in mind, I'm not saying which is better or worse. A good team with a good suspension, good drivers, etc can win with any layout. It's the sum of all the components that make the package & the quattro team had the best of everything. Well done to them!

Another 2 points afre that the Audi was very reliable. They had only 1 non-finish the whole year & that was an exclusion. Next year they lost, EVEN WITH QUATTRO. SO the other teams caught up & made a plan to counter quattro's advantages. Like in F1, teams will adapt.

http://freespace.virgin.net/tjl.theg...udihistory.htm

After an eagerly awaited arrival, Audi took the BTCC by storm from the moment the lights went green on the first race of 1996. The 4WD A4 won it's first three outings of the season of that year and dominated the rest of the championship. The teams stringent engineering standards were an important part of the success of the operation, with parts 'lifed' and tested to an extent that had never been seen in the BTCC. Audi Sport in Germany provided engineering assistance but Audi Sport UK ran the day to day operation. The teams only non finish all season was when Biela was excluded for a driving offence at Snetterton. A combination of supreme traction, reliability and driver skill ensured that Biela, Bintcliffe and the A4 formed the perfect partnership, winning both the drivers and manufacturers championship at the first attempt. Frank Biela went on to take a total of 8 outright race wins on his way to winning the championship.
Frank Biela - 1996 Audi A4 (4wd)


John Bintcliffe (front) & Frank Biela - 1997 Audi A4 (4wd)
1997 saw Audi carrying a weight penalty (95kg) due to the dominance of the proceeding season, although this was reduced by 30kgs later in the season. The driver combination remained the same but the luck had changed. Lack of winter testing with the new car ensured the problem free season of 1996 wasn't repeated. The first ever retirement of an Audi A4 was seen in the very first race of the season at Donington Park. Sadly for Audi the car was to repeat the performance at Silverstone as well. After the euphoria of '96 it was a disappointing start to the '97 season. However things improved as the season progressed and Audi still took 7 race wins (Biela 5, Bintcliffe 2), and managed to finish 2nd in the drivers and manufacturers championships. Not a bad swansong for the quattro in the UK.

 

The turbos (or a centrifugal blower) would be the most efficient way to make power, and you would already have a ton of torque from the larger displacement.

I doubt the Kleemann blower in it's current trim would push enough air for a 6.3L motor.

 

throttle response is due to the actual throttle body., opening and closing..

thats nothing to do with if its a FI or NA car.....

my 02 cent.

 

Fair enough, you can have an FI or NA car with 8 individual throttle bodies & an instantaneous response on the throttle plate when you touch the throttle. It springs open. BUT, once the throttle is open the air needs to flow in. In which setup does the air start entering quicker?

 

I think it is quite clear - and we all agree - a turbo charged car throttle response has a degree of lag - if this is what you mean by throttle response.

I think what throws people is two things ...

Firstly a NA car will have good TR especially the new VVT type motors from Honda , Toyota , BMW etc ... Lets face it this has been a massive step up in engine develpment - they can produce much better torque at low rpm than before - and spin to massively high rpm ...

Secondly on a S/C motor boost is present almost permanantly assuming the S/C is always engaged. At low rpm a S/C car has massive power giving - to me at least - instant power... there is no lag whatsoever in my experience on the E55. The the C32 was not nearly as good when I drove it - think it may have been due to poor Octane fuel though. Still quick but definately a lag present.

So I think its down to the specific application - the E55 to me has instant TR, the C32 poor , most turbo's much worse ... but then again look at the CL/SL65 ... OMG - you could never say that suffered from poor TR ... could you ?

When you have a large SC engine (5litres plus) allot of the lag / parasitic loss is absorbed so the TR remains good.... if its as good as NA ... ?? I think its a very close call. If the motor is a small SC unit the lags / losses are not able to be absorbed as well ... so here N/A will be sharper for sure I think. Look at a C32 vs M3.

Rgds Steve.

 

I'd bet my last dollar that less than 1-2% of owners of cars with a sticker price of more than $50,000 modify their engines in any way. The vast majority of AMG and M owners see their cars as tuned for extreme performance already.

~ Ian

 

Keep your $.02 timmy. You're going to need it for a good education in the field of internal combustion reciprocating piston engines. You don't have a clue.

 

Hey M&M,
You are still missing the point WRT AWD. Regardless of what type of system it was (viscous or not) the fact remains, AWD dominated until it was either banned or penalized.

 

Throttle response isn't just about the air entering quicker but close enough for a layman's terms. You have to agree that the answer is "It depends on a lot of factors". Things like displacement, compression, rod length, stroke, piston pin placement, valve lift and duration, cam overlap, valve size, combustion chamber design, exhaust scaveging, intake port shape, length and volume, throttle diameter and placement in the intake tract, state of tune, ignition performance, ECU ability to respond quickly.....(have I left anything out?)...oh and gearing, vehicle weight....all have an effect on what is perceived as throttle response.

 

Yeah, that's why GM, Ford, Mercedes, Jaguar, Mazda, Rover, Mini, Porsche, Subaru, Saab, Toyota, Mitsubishi, Volkswagen, Lotus, Bugatti, and Bently have all dropped their line of superchargers and or turbochargers from their line of cars. Not a clue!