hi All;
Newbie here. I hope this is the best place to post this on the forum.

I am working on a project car and considering the RS6 4.2 twin turbo motor coupled to an 01E (rebuilt/beefed up) 6 spd. I am trying to learn as much as possible about this engine and try to find one at the same time.
The engine that catches my interest and meets my specifications is from the 05 or 06 A6 RS6 Avant.
It is listed, as I'm sure everyone knows, at about 473hp. My goal is about 425Whp so this is pretty close.
It's competition, by the way, is the GM LS4 engine which can provide 425whp normally aspirated, but poses some significant 'dimensional' challenges for me. (It's BIGGER!!)
From what I can tell the 4.2 is only about 18" long which is remarkable. And it fits the space I have.... which is the real biggie.
So if anyone can point me to articles and links on the 4.2 turbo's reliability, problems and potential sources, I'd appreciate it very much!
Thanks in advance for all and any input.
GP

 

you can't get an 05/06 rs6 in north america as they only allowed the 03/04 sedan into NA. That engine has 450hp and if you go onto rs6.com you'll see the engine is fairly bulletproof. All the torque it produces is hard on the auto trans it has and some owners are now going 6 spd.

 

Thanks Bakes;
I just took delivery of a 40v 4.2 last nite; the car he took it out of had the door label showing '02-00' so I am not sure which year it is yet; 02 or 00. I am getting the VIN so will find out for sure.
For now this engine looks like it is/was about 315hp and a 6000+rpm redline. For now I am going to use it as a 'core' for measurement and building up the custom framework etc that I will need.
IF I go ahead with it in my project, I am also hoping to twin turbo it; it appears the compression ratio for all these 4.2's is 11:1 including the turbo'd versions. So I assume it runs on low boost. I don't see anything else like water injection in the stock versions of course but I need to investigate further.

I would also have to get my ecm reflashed or get a new/proper one. My preference is to go with an oem audi ecm over an aftermarket one.

Is there an audi forum that 'specializes' in turbo'd cars?
I see there are a lot of forums....
thanks for the input.
GP