Would a stripped out FL S8 manual be a good track car?

[nakata]

Which car is better on track, 90 quattro or RS8?
Rear LSD(torsen or something else) is great on track.

[Goran]

Originally Posted by RallyQuattro

Why do you write RS4 every time?
RS4 and RS6 are two completely different cars

RS6 rear diff with mounts fits directly.
But there is nothing special inside RS6, It have the same open diff as A8/S8 the only difference is the cooling plate on the underside.

What I have done is I have bought an LSD and fit it inside my RS6 diff, but that you can do also in your A8/S8 diff
I have also installed a temp sensor on my RS6 diff.

.

Sorry for confusion, I mis-read I thought you used a RS4 diff in your S8.
So its easy to fit a LSD into the S8 read diff casing? Is it a LSD from some other car or custom made?
With standard S8 open diffs I have had wheel spin and losing grip on wet round-abouts when applying power in 1st and 2nd gear so maybe a LSD will help.

[RallyQuattro]

I spent a lot of time and money on my old Audi 90q -1985 with 20v turbo engine.
with a lot of custom built parts on that car and i drove it for many years on the race track,
But even though my new RS8 weighs more I have already driven faster on the same race tracks and I have a lot more things I plan to do with this car.

The A-arms is so much better than the old MacPherson strut.
And the D2 body is much more stable.

And it is possible to reduce the weight if you like, to the same weight or lower than an old 90 quattro.
I have plans in the future to build a new light weight A8 race car without sunroof, tow bar or car stereo and with plastic windows and so on.



And No I don't have a Torsen in the rear, Torsen and quaife will work nicely between the front wheels but I would never mount that in the rear.
I have a real Limited Slip Differential gear with lamella (plated type) in the rear.
(Same type as Porsche, Bmw M3 and all other fast race track cars have.)


.

[nakata]

Good to hear this information about comparison.
A/S8 have a great potential for track car. Even with biturbo engine
I have torsen diff at rear, and find a big improvment when install it. Imagine what is it with true LSD

[Goran]

Thanks for your advice, its good to know, LSD for the rear, and torsen for the front. I doubt I will track my car but even on the roads the front and back open diffs sometimes do not perform great.
I love the D2 platform as well, your RS8 weighs about the same as a B6 S4, a car two sizes smaller!

Is your rear LSD on your RS8 a custom made or is it from another car?

Thanks

[RallyQuattro]

There are several manufacturers out there in the world that produces these LSD for different car brands both to the gearbox and rear diff, so mine is one that is made for Audi rear diff.

If you are going to drive drag race or drift with your car then Torsen will not be good at all so then you need lsd also in the front.


And mr nakata if you have Audi V8 oem torsen rear diff mounted in your car then you should not have to much power in the engine because then it will explode.
It will only hold for maybe 5-600hp.

[Goran]

Thanks! I will remember LSD front and back to replace the open diffs.
I will ask around how much it costs to make.
I do like drag racing at GTI international and fast starts off the lights (when there is no traffic around).
Have you done a 1/4 mile or 0-60 in your car, I'm really curious how fast it accelerates with so much torque and hp and such light weight.

[RallyQuattro]

It is too difficult on the street and with manual transmission to test 0-60, but I have test from 60-125 mph

Or 100-150km/h and 100-200km/h

But this will be even better times this summer, with new larger injectors and higher boost pressure

.

[andycaca]

any change of a 0-60 comparison? my sprint car (4WD celica Gt4) can do it in a consistent 3.8 seconds. no idea on the quarter mile time

[RallyQuattro]

I have not built a drag race car and it is difficult to do a perfect start from 0-60 with normal street tyres on the road, especially with a manual gearbox and without any launch control or other helping system on a big Audi S8 with over 800Nm
And I also don’t want to break my gearbox only to get a low 0-60 time on my car.

And with manual gearbox and street tyres, if you get a low time I would say that the credit for that is maybe 40% the engine power, 30% the grip of the tires and 30% is the driver that launch at right rpm and change gear at right time.
So there are several factors that affect the time and not just the engine power.

But if you are running on one gear 60-95 mph then it is 100% engine power which gives a good time.
But for 60-125 mph then I have to change one gear from 3rd to 4th so then it's maybe 25% of the time how quickly you can switch and the rest is pure engine power.

So best test between cars is 60-95 or 60-125 mph
Or in my case 100-150km/h or 100-200km/h

My car last year did 100-200km/h on 7 seconds

Here I found a comparion chart for 100-200 km/h times on fast stock cars but that are slower than my car

7.0 - Mercedes SLR 722 - 650hp
7.1 - Corvette ZR1 - 638hp
7.2 - Porsche 991 turbo S 2013 - 552hp
7.2 - Lamborghini Murcielago LP 670 - 670hp
7.2 - Mercedes SLR Stirling Moss - 650hp
7.2 - Mercedes SLS - 563hp
7.2 - Mercedes SLR - 626hp
7.2 - Audi R8 V10 Plus (2013) - 550hp
7.3 - Porsche 911 997 GT2 - 530hp
7.4 - Ferrari 458 spider - 562hp
7.4 - BMW M6 (2012) - 560hp
7.4 - Ferrari FF - 660hp
7.5 - Porsche 911 Turbo S (2011) - 530hp
7.6 - Ferrari F430 Scuderia - 510hp
7.7 - Lexus LFA - 560hp
7.8 - Lamborghini Murcielago - 580hp
7.8 - Nissan GT-R (2012) - 550hp
7.8 - BMW M5 (2012) - 560hp
7.9 - Corvette C6 Z06 - 513hp
7.9 - Porsche 911 GT3 RS 4.0 - 500hp
8.0 - Ferrari F50 - 520hp
8.0 - Ford GT - 550hp
8.0 - Viper SRT-10 2008 - 612hp
8.4 - Ferrari F430 - 489hp
8.4 - Lamborghini Gallardo Superleggera - 530hp
8.4 - Aston DBS - 517hp
8.6 - Porsche 997 Turbo manual - 480hp
8.6 - BMW M6 V10 - 507hp
8.6 - Jaguar XKR-S - 551hp
8.7 - Mercedes SL65 AMG - 612hp
8.7 - Nissan GT-R 2008 - 480hp
8.7 - Lamborghini Diablo VT - 492hp
8.8 - Audi RS6 - 579hp
8.8 - BMW M5 V10 - 507hp
8.8 - Mercedes C63 AMG Black - 457hp
8.9 - Mercedes S65 AMG (2008) - 612hp
9.0 - Porsche 996TT X50/Turbo 'S' - 450hp
9.0 - Porsche 997 GT3 RS - 415hp
9.1 - Lamborghini Gallardo SE - 519hp
9.1 - Audi S8 - 520hp
9.7 - Porsche 996 Turbo - 420hp
9.9 - Mercedes E63 AMG -525
10.5 - Audi RS5 - 450hp
10.6 - Audi R8 (2006) - 420hp
10.8 - Porsche 993 turbo - 408hp
10.9 - BMW M3 E92 - 420hp
11.2 - Aston Vanquish S - 528hp
11.6 - Audi RS4 Avant (2012) - 450hp
10.2 - Porsche 996 GT3 - 360hp
11.0 - Audi TT RS Plus (2012) - 360hp
11.6 - Mercedes SLK-55 Black (2006) - 400hp
12.4 - BMW E46 M3 - 343hp
13.3 - Audi S5 - 354hp
14.6 - BMW M3 E36 - 321hp
15.3 - Audi TT-S - 272hp
16.4 - Subaru WRX STi - 280hp
17.9 - Audi TT 3.2 (2007) - 250hp