Anyone have an estimate of relative allroad 2.7T engine performance at high altitudes - say 10,000 ft? Turbo should compensate for thinner air to some extent, but will eventually run up against some limitations I would think. Any real mountain drivers out there? Also, how's the turbo lag at these elevations?

Thanks.

I don't think Audi sets up the turbo system to maintain absolute pressure for boost so you will lose some performance.

In my A6 I noticed very little difference. Maybe about 3-5%. It was far faster than other cars at altitude though if the were non-turbos. Lag was no different. I really noticed no appreciable difference.

Well, I do drive at altitude but I don't have a lot to compare to...

I live at 8600' commute down to 5400' daily. There is no decernable difference between the two. Power is there when ever you want it. I haven't had the car above 9000' so can speak above that but would expect pretty much the same performace.

There is some turbo lag, if revs are down but I consider it normal and will downshift to get RPMs up to get things moving quicker if I need to.

It is hard to quantify as I've never driven an allroad a low altitude. I will say the lag is a whole lot less in the audi than other tuburo's I've driven (Porsche, Toyota) but I attribute that more to the biturbo engineering.

fj..

I posted a little report in January. I live in Colorado and go ski from Denver to the high-country every weekend.

One good test was to have 5 people with all the gear and skis on top to Vail. That's 2 passes (Loveland and Vail) and I think that Vail pass is at about 11000 feet.

I was able to keep the car in 6th gear all the way, was able to accelerate to pass near the top of the passes. I'm very pleased with the performance. Turbos are the way to go at high altitude. I know for sure that non-turbo engines lose 17% of efficiency at 5000 feet, conservatively, I expect them to lose at least 25% at 10000 (I don't know if the loss is linear). I didn't notice a difference whether I was in town or on top of a pass.

As for the turbo lag, it needs some getting use to. They claim that you have most of the power right from 1800 RPM. I bet that with the semi-automatic (tiptronic), you couldn't feel any lag.

It's a great cruiser. Just don't expect stellar quality on the manual gearbox (clunky in 2nd and 3rd).

Just got back from 4 days in the sierras at 8000-1000 feet. The turbo worked great, better than my previous A4. I have a neuspeed chip and not sure how much that helped but I was more than pleased with the performance.

My '86 2.2Turbo Quattro maintained full power through the 10,000 foot level. This is also described in the tech manuals in that you looked for different boost readings for different altitudes. When you chip the older turbos you gain HP at lower altitudes but eventually end up at the same power somewhere above 8000 feet. I suspect, given the conservative power output of the stock 2.7T that the same will be true. Probably 320hp at sealevel and 250hp at 8000' with a chip, or 250hp from sealevel through 8000' stock. Just my two cents as an aviation mechanic with much turbo experience. silver 00' 2.7T 23000 miles, enjoying them all