Dyno vs on-road whp

[rs6_newyork]

I read some article about the need for dyno testing to be done in wind tunnels or with extremely serious wind machines, because the ecus in modern cars (BMW M5 was an example) track air flow and pressure in the front, and if you're running the equivalent of 100mph when stationary, the computer knows it isn't getting the air it needs so it backs off. Dramatically improved whp figures are obtained by increasingly powerful fans, but even the largest shop fans cannot match the effect of a 100mph bow wave of air being rammed into the front of the car.

So I'm wondering with all this talk of chip vs stock WHP, and loss due to drive-train etc, whether the same lack of oomph is seen with the RS6 as with BMWs when tested on a dyno without a 100mph wind machine?

[rs6_newyork]

btw, somewhat related:

http://www.autospeed.com/cms/A_0827/article.html

I wonder how much a shop would charge to do this mod? It is a really cool mod, especially the integration into the audi dash of lights informing you when the intercoolers are being misted :)

[Speed Technik]

You want to talk about wind tunnel testing. All of the OCT software is tested in a wind tunnel and is very close to what we were seeing on our Dynapack. I can not comment on APR's, GIAC's, MTM's or Sportech's wind tunnel testing because as far as I know, they don't. If I am wrong, let me know and I will edit this post.

[Nordschleife]

Originally posted by Speed Technik
You want to talk about wind tunnel testing. All of the OCT software is tested in a wind tunnel and is very close to what we were seeing on our Dynapack. I can not comment on APR's, GIAC's, MTM's or Sportech's wind tunnel testing because as far as I know, they don't. If I am wrong, let me know and I will edit this post.

Depends what you mean by a wind tunnel.

OCT do not have a wind tunnel. OCT does have a standard Chassis Dynamometer installation.

In Europe chassis dynos have to be properly soundproofed, all emissions processed and high standards of environmental safety adhered to. Doing all this makes it easier to also include fans which drive air into the radiators and intercoolers.

This is what OCT has, its also what MTM has and Sportech has and... and... and..... whilst this might be unusual in the US it is completely standard here in Europe.

Workshop practices are quite strict in Europe.

R+C

[rs6_newyork]

Originally posted by Speed Technik
You want to talk about wind tunnel testing. All of the OCT software is tested in a wind tunnel and is very close to what we were seeing on our Dynapack. I can not comment on APR's, GIAC's, MTM's or Sportech's wind tunnel testing because as far as I know, they don't. If I am wrong, let me know and I will edit this post.

Well, there are wind tunels and wind tunnels. In order to simulate full power at 100mph correctly you need more than a few blowers pointing at the front of the car!
but what i was really wondering was if anyone knows if the RS6 engine ECU recognizes a "low wind" vs "normal" condition, and dials back power when not getting a realistic amount of air, the way the M3 is reported to do.
And the article (in road and track, or C&D), insinuated that the HP drop seen was much more than is accounted for by air (not) getting "rammed" into the engine. They suggest it is a result of the new ECUs, and was not seen so much before on dynos.

[gjg]

so what is the story with OCT wind tunnel - standard procedure like everyone else or the real bick bucks stuff?