Since I work for VW/Audi Lab in Cali, the boss of our lab had the first RS4 in NA before they were released. All of you who have the car must know most of the important info about it already but here is something I found out recently.

1) The NA 4.2L V8 in the RS4 has the highest mean piston velocity at redline of any production car. 28m/s

And here is the warning:

2) The engine can actually rev faster than the tach can. So in neutral the engine can be bouncing off the rev limiter at 8250rpm while the tach needle is still around 7k!

Watch those revs guys!

 

That sucks...do they plan a fix.

 

Ill try not to redline it in neutral

 

That sucks. I wonder why the gauge is that bad?

 

I believe Audi is aware of this because I remember it being brought up a few months back with problems over in Europe. I'm curious to see what they'll do.

 

smart man

 

so, is it accurate when driving??

 

Are you sure about that? How does the F20C S2000 engine compare in terms of piston speeds?

 

the hondas has a higher RPM but its designed with a very shrt stroke and large bore, where as the audi is more "square"

 

I know tuners who raise the redline...

 

by how much?

 

Some guys were having a huge discourse on S2ki.com about raising the limit to 9,000 (from 8,200). The problem is that the piston speeds cause the rods to bend... Not fun. There is a ton of physics/math/trivia if you look up the thread.

 

Holy crap, 800rpm increment? That's a crapload for such a already high strung engine!!!

 

I had both an '01 (w/2.0L, 9K redline) and an '04 (w/2.2L, 8.2K redline) and I can honestly say the bigger motor was much better. The numbers don't seem like it, but the torque is much more noticeable in the 2.2L. The guys who wanted to bump the 2.2L were whining about the "low" redline...

 

Actually, the problems with the 2.2L spinning to 9k came from sideloading, the piston against the bore, not from bent rods. Also, if I remember correctly, due to the increased bore, the 2.2L 8200RPM engine actually had higher piston speeds, but I may be wrong about that. It's been a while since I've seen anything about that.

After driving both the 2.2 and 2.0L engines, I prefer the 2.0 for hard driving and the 2.2 for around the city. No surprises there.