What air temp did Audi test at to get 450 hp?

[Hy Octane]

During the summer here in socal the temps got over 100 and this motor lost at least half of its hp. Now we are in the middle of a cold spell ( 40-60 F) and the car is making incredible thrust. Does anyone know what air temp Audi dyno's at to get 450hp? Does anyone have a table of approx. hp loss/temp ? Looking for a possible solution,, anyone?

[GoFastKindaGuy]

Power numbers are corrected for atmsopheric conditions at test time. The observed power may be higher (or lower!) in cooler temperatures. That is a function of the calibration in the ecu.

Unlike naturally aspirated engines of yesteryear, some boosted and electronically controlled engines actually perform better in warmer temperatures (due to the boost control algorythms employed).
:idea:

[Nordschleife]

tested at the ISO standard temperature, humidity and airpressure, or adjusted thereto. This is mandated by EU customer and environmental protection laws.
R+C

[k2]

HyOctane ... I live in Boca Raton, FL. Same thing was happening with me ... during the summer months when we experience high humidity and high heat, my RS6 was very tired off the line (lag & lower hp). I now drive a GT3 for the track but still have a turbo'd family ride. My CayenneTT has issues during the summer like my RS6 did (some were solved with K&N filters. I don't think I'll ever go back to a boosted track car ... but then again I've never driven a Noble.

Good luck with your situation. I don't think there is a lot that can be done unless you tune your car and even then I'm not sure what you'll get.

k2

[nene]

I'd bet they used 'room temperature'. Given that the numbers are probably coming out of a dyno anyway, the car would be in a garage.

Either way though, what you are observing has been true for any of Audi's turbocharged engines. When I had my S4, I never took it to the drags over the Summer. Always Spring and Fall.

[audirs6sport]

This was while ago. Someone actually posted his/her dyno results of a "stock" rs6 in metric units. (don't quote me on this, for those of you who just love to use that quote button. you know who u are :D)

[Hy Octane]

tested at the ISO standard temperature, humidity and airpressure, or adjusted thereto. This is mandated by EU customer and environmental protection laws.

Well thats a great answer Nord, but I guess what I'm asking is does anyone know at what temp F the 450 hp begins to drop due to heat and how much it drops per 5 degrees or so??

It would help decide if a chip might be helpful for summer months,,..

BTW I am aweare of the turbo heat sink loss of power issue. My 91 20v turbo 200 quattro suffered from it as does my 94 S4. :s4addict:

[Nordschleife]

A smart intercooler spray, or direct water injection would help solve your power loss problem. It is greatly aggrevated by poor grade gasoline however, so do make a point of filling with the highest possible grade and octane rating gasoline.
R+C

[GoFastKindaGuy]

Pure answer to your question: It the range of temperatures we're driving in, correction is about 1.5-2% drop in power for each increase of 5 deg F -- if all else remains constant.

Qualifiers: I don't know if Audis turbo setup is electronically modulating boost bypass, if the intercoolers are modulated to reduce the difference between ambient air and charge air, or if the calibration adjusts with temperature/humidity changes. All of these are likely and will change the "pure answer" above. Some good Audi tech should be able to describe what is going on and how to address your issue.

[7:53 RS6]

My car always go limp(do not preform as it should) when I get "over" 120c in oiltemp. As soon temp go down to 120c or below all is ok.

Can say that I never have reached 120c in street driving or at fast tracks, but for obvuisly reason on shorter track.

What I undertand this is a safe gismo to prevent overheat.
I do not now fore sure but it should be some sensor in engine that feels when oil get to hot and then put car in limp mode I heard.

So if better heat resistent oil its possibel to not get 120c as fast?

Well this is maybee an other ballgame than the above post? but anyway.
Can some one se in manuall if its a gismo and how its works. Cant reach mine fore now.

[espen]

Most ISO standards go for 20 degrees C. Turbo engines benefit imensely from cold air, if the engine will support it, 3 degrees at the intake ca be worth 1% power. So a -15 degree winters day here could theoretically push an RS6 into the 500s.

We measured a chipped Audi A3 (MTM chip, ported intake manifold, Ramair cone, full exhaust - IC is a bit small!) at ~200hp and 7.8s to 100kph after some runs in sunny summer weather (not best run but seemed to stabilize there.)

Then on a 0 degree foggy day in march it put out over 215hp and dipped consistantly into high 6s to 100kph. Of course the owner had gotten a bit more practice over the winter, but the extra power was immediately noticable.

Either way, these are real world raw figures as measured on the spot using GPS based proper equipment. If ISO corrected, i suppose the deviance might be pretty much zero.

[freerider]

There several solutions, but non are cheap.
The extra power given by the turbo is by giving compressed air to the engine (simply said). But you don't need to get more compression(not entirely true), you need more air molecules. And when air is hot, it expands, so same compression, but less molecules -> less power. A turbo is powered by the exhaust (reason turbo lag), so the air is hot, but after the turbo it's getting cooled by the air outside, but if the air is hot it doesn't cool as well as cold air, so you loose molecules because of the size of the air. There are some solutions, but none are cheap (as said before). You can read all about it on: http://auto.howstuffworks.com/turbo1.htm
The solutions are also there. I can give you more sites, but i prefer this one, because of it's "easy" language and good illustrations.

http://www.superflow.com/support/support-engdyno-how-is-torque-meas.htm

Hope it helped.

Greetz Johan

[freerider]

I think i found something more: Rating Standards. (what conditions the car was tested in to get its power rating)

EEC: European standard. Measure at 99kPa and 25°C. Rated in kW.

SAE: American standard. Measure at 99kPa and 25°C. Rated in hp. 1kW = 1.341hp (SAE).

DIN: German standard. Measure at 101.3kPa and 20°C. Rated in hp (ps). 1kW = 1.360hp (DIN).

JIS: Japanese standard. Theoretically same as DIN

British Horsepower: same as SAE. Rated in bhp (could be confused with brake horse power).


Greetz Johan

[Aronis]

howstuffworks.com is a fun website..

I have read that page before, it's a great discription of how turbo's work etc...