fusilier

A short wheel base D2 with no interior finish. Doors stripped. Lexan windows in the doors. No roll cage.

Does anyone know or care to make an educated guess?

As the cost of used A8s get down in price, it seems like they could make a really good track car. The Alloy frame is cheap and since its a space frame... One could run the car with no body panels to take off even more weight. Its got quattro with is good :-) The motor is decent for the track. Figure out how to bolt up a 5 speed from some other Audi and its all set.

I think the frame is about 2mm thick compared to a steel frame which is about 1.3mm thick. Aluminum is 1/3 the weight of steel. So if a steel car chasis like an A6 weights 3000 lbs then the A8 might weight 1700 lbs?

AntiSocial

Vote to ban.

fusilier

Another *** post from Antisocial.

If Audi can strip down an RS6 why is a stripped A8 a bad thing?

It has a modern suspension. Big brakes out of the box. Good NA engine. I am seeing 1997 A8s go for 15000 or so(a real bargain). If 50% of the weight is interior trim then they'd make great fast cars. The transmission thing is the only drawback but it shouldn't be too hard to mate up a 5 speed from another Audi.

Do you even have an A8? I drive a 2001 A8L as my daily driver. If your serious then you can KMA. LOL

GDJT Allroad^2

For about $7k you can find out; that's the going rate for a very high milage '97 A8 at auction.

If you really wanted to do a transmission swap cheap what I'm about to suggest isn't legal....

Find a wrecked, totaled, destroyed A8 here, stateside. Make sure it has a title. Find your cheap, high milage stick-shift A8 in Europe. Ship it to the states. Swap the VIN numbers from your wrecked, US-spec A8 for the Euro A8. I've heard of people doing this with 240SXs and importing Nissan Skylines that way.

If you search through the archives you'll find lots of pages of discussion on doing a six speed swap. I'll summarize what I remember...
A8 does have a punch out plate in the floor for a clutch pedal.
You'd need an entire clutch pedal assembly and fluid resivoir.
In addition to the transmission you'd need a new rear-end, as the final ration of the six-speed is different than the auto.
It may or may not work with the US-spec ECM/TCU.

ryoung

Aluminum is much lighter than steel, but it's also much weaker. The relative strength depends on how it's measured (tension, compression, bending, fatigue, etc), but in general expect only about a 10% weight savings from using aluminum versus steel.

Comparing an A6 and an A8, many components are either already aluminum in both (engine, transmission case), or steel can't be avoided (gears, brake rotors). IMHO, getting an A8 down to "only" 3000 lb would be a serious challenge.

fusilier

I recall seeing two people easily lift an A8 frame. The body paneling isn't structural on an A8.

Whereas I doubt two people can lift an A6 unibody.

Conclusion #1 in the link regarding the a8 chasis is a structure weight savings of 45-50%. If the A6 weights 2000lbs then the A8 must weigh about 1750lbs or so? Many components in the suspension and drivetrain are steel but what percentage of that is the total weight.

My best guestimation is that an A8 fully stripped out with no AC and other gizmos might be down around 3000 lbs. Maybe less!
Heck the seats are whoppers. And the double lined carpet with layers of sound deadening material. Weld in some aluminum structural panels and it would make a mean racer.<ul><li><a href="http://www-nrd.nhtsa.dot.gov/pdf/nrd-01/Esv/esv16/98S1W20.PDF">http://www-nrd.nhtsa.dot.gov/pdf/nrd-01/Esv/esv16/98S1W20.PDF</a</li></ul>

fusilier

So this begs to ask the question. How much does the unibody on an A6 or any comparable weigh.

An example. MB shaved 500lbs off the structure weight from the 99 S430 to the 2000 S430. This was done by using alot of aluminum and high strength steel. So the S430 now weights about the same as the A8 (4100lbs).

If the difference is 400-500 lbs between a steel frame to an aluminum frame, then that would put a stripped A8 down around 3000lbs compared to 3400 lbs for a stripped A6. Is the A8 carrying 1000lbs of creature comforts?<ul><li><a href="http://www.germancarfans.com/news.cfm/newsid/2020715.001/page/3/audi/1.html">http://www.germancarfans.com/news.cfm/newsid/2020715.001/page/3/audi/1.html</a</li></ul>

Sven_S8

Not a clean comparison perhaps, but maybe it helps.

My S8 weighs 1725kg (certified on car papers), the RS6 (saloon) weigs 1840 kg (avant 1865 kg).

So imho there would be a weight saving. Also, the S8 is more neutral as the RS6, due to the engine placement. As you may know, they had to lengthen the front of the RS6 (any V8 6) to fit the engine. Hence the oversteer tendency of the 6.

For this reason, folks who owned both cars think the S8 may well be able to keep up with the more powerful RS6 on a track, or even have an advantage on some (curvy) tracks...

As said, I can't offer you the 'net' weight comparison, but taken into account the S8 has probably more 'goodies', the actual difference may even be more.

I too believe aluminum is stronger, as this seems generally accepted. (I'm no engineer tho). The only issue may be the body repairs perhaps?

An S8 engine with 6 speed manual will be the ultimate for the purpose I bet.

Good luck with the quest! Keep us posted. ;-)


PS: the lightest A8 Q (2.8) weighs 1495 kg, 2.8 FWD = 1435 kg. (not too bad a difference for a Quattro)

GDJT Allroad^2

Leather seats, carpet, glass add up.... but maybe 500lbs, not 1000

fusilier

The carpet is in the range of 100lbs.
I can see 500lbs easy. 1000lbs may be a bit high, but definately more than 500lbs.

The stereo,speakers and wiring might be about 100lbs. The AC is about 75lbs or so.

either way, its an interesting proposition.