turbo, supercharge / 4.2 mods?

[A\/anT]

Im looking at a used A8 to purchase (its a 2001) and i love the car!! Indeed it is the big boy of audi's Im looking for modification's engine wise, i know theres a biturbo 4.2 in the RS6, im wondering if anyone made a turbo 'kit' available for the n/a 4.2 yet? Or any supercharger kits at all? I cant find an S8 in my pricerange so.. thats why im asking

[chucklane]

[April]

Can be done ( I think some German tuners have done it with manual cars ) if you bring enough cubic dollars to the table.

I remember that early versions of the RS6 melted all kinds of things under the hood due to the heat.

[A\/anT]

[FLYTERRA]

Hopefully it will be just like the Audi 2.8 kit with no further mods required. The A8 tranny is rated at about 360 lbs of torque so be looking for a 50-100 hp gain out of the supercharger. This would seem to be enough to have S8 power and a altitude engine.
The last time I called PES they didn't have a completion date so give them a call and let them know you are interested. Maybe if all those interested would do this they would push the date foreword.
Also if you are looking for something in the meantime, they have a chip that will remove the speed limiter and give you about 20 hp. I have it and it works well.

• http://www.pes-tuning.com/oldsite/index.html

[April]

and not enough are sold to make it worth the R&D time for most tuners. Just think, peak sales here in the past have been 4500 cars a year. Of which maybe 5% want to change SOME aspect of the performance - be that brakes, suspension , wheels, or engine. Now most are going to max out around the $1 to 2K range.

Of that 5%, maybe .5% WANT to do serious engine mods. Of that group, and even smaller percentage are going to want to PAY $10K or more to do a properly engineered conversion ( remember that you'll be cutting up a very nice $40 or 50K car so a half baked conversion isn't going to fly by most folks standards.

[April]

and S6 ) which has a front mounted timing belt, or the new ( new A8, Allroad, S4 ) V8 with the timing chain in the rear of the motor. Not likely to be an interchangable system.

[mclarenm8d]

A 2001 is still an expensive piece, and to points below, after you apply a charger you will be close to the cost of an S8. In my mind, a candidate for a charger would be a high-mileage 97-99 A8 that you can pick up for cheap and that needs overhauled anyway.

IMHO, a charger kit for the 4.2 will come from the application for A6 4.2's, and the engineering of that will be an extension of work on 2.8's and 3.0's in A4's and A6's.

[Xialater]

don't hold your breath!!!!!!!!

[skiwi]

it's just that, as a n/a car it is harder to do.

if anyone thinks that a supercharger (usually a turbo) is just a bolt-on, you're wrong. to do it properly, you need to factor in a number of things:

1) intake cooling (intercooler) - requires siting, plumbing, and engineering (limit pressure drop).

2) boost control - requires a wastegate, computer management and plumbing.

3) idle control - to avoid pressure spikes, you will require a bypass valve or (shock horror) a pop-off valve.

4) computer modification: engine map now needs to understand boost, and be able to be adaptive due to one of either boost pressure, petrol quality, knock, or failure.

5) engine modifications - lower compression ratio - the a8 runs at too high a compression ratio for supercharging. valves especially exhaust might also need to be changed.

6) details: plumbing, cooling etc - all require more work as the supercharging device (usually a turbo) generates a lot of heat.

for the above reasons, and a bunch of others it is far far easier to start with an engine which already has a supercharging device attached.

for instance, you could take the v8tt motor out of an rs6 and put it into the a8 with a lot less difficulty than adding a turbo to the a8 v8. there at least the majority of the work is done for you.

i prefer the s8 to the rs6 as a drivers machine anyway, although the rs6 tranny is better.

hth,
dave
'01 s8