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p3u
September 1st, 2009, 18:20
I drove down to Corpus Christi, TX for a visit, first time I've had the beast at sea level, and I have to say :bigeyes:

I didn't think there would be such a difference, but almost no turbo lag followed by even more brutal power makes me grin from ear to ear! I may have to move! lol

Now I truly know the power of the beast, in stock form anyways :)
vangelis
September 1st, 2009, 19:11
Might be stupid, but Why is that makes any difference in power? please explain!!
p3u
September 1st, 2009, 19:21
Higher elevation equals less oxygen, less fuel can be burned, less power, more turbo lag.
sheatisdale
September 1st, 2009, 19:29
The closer you are to sea level, the denser the air is.

Just think of the atmosphere like you would the ocean. The deeper you go into it, the heavier and denser it would be. That is why deep in the ocean it can crush submarines and such.

The air is the same way, just thinner. So the closer you get to sea level, the denser it is and thus the more oxygen it has per cubic foot.

Assume 75 degrees F.

At 6800 ft air density is about .0574 lb/ft3 (pounds per cubic foot)

At 100 feet above sea level is it .0735 lb/ft3

So you can see that the difference is pretty dramatic. The air his car was breathing was nearly 30% denser and thus had nearly 30% more oxygen in it.
vangelis
September 1st, 2009, 20:04
I google Abu Dhabi city where I live and I found it 88ft (27m).
SAF
September 1st, 2009, 20:52
I drove down to Corpus Christi, TX for a visit, first time I've had the beast at sea level, and I have to say :bigeyes:

I didn't think there would be such a difference, but almost no turbo lag followed by even more brutal power makes me grin from ear to ear! I may have to move! lol

Now I truly know the power of the beast, in stock form anyways :)

Where did you start? Not in Texas?
Mr Balsen
September 1st, 2009, 21:05
The famous Audi S1 Pike's Peak is 1000hp at sea level, about 750/800hp at the start of the Pike's Peak race, and 500hp at the end...

Frederic
p3u
September 1st, 2009, 21:06
I'm from Colorado Springs. I'm loving it down here! :)
p3u
September 1st, 2009, 21:07
The famous Audi S1 Pike's Peak is 1000hp at sea level, about 750/800hp at the start of the Pike's Peak race, and 500hp at the end...

Frederic

I beleive it! I've been up the Peak many times, and each time I go I always seem to loose a few cylinders and a turbo on the way up :)
RS6-4dr911
September 1st, 2009, 21:36
However, the difference is not nearly as stark with a well controlled turbo car like ours since the turbos will be asked to keep providing boost until the requested amount (I seem to recall the ECU is requesting absolute pressure, not relative pressure, otherwise, this would not be the case) is created. I suppose there must some altitude beyond which our turbos just can't create enough air volume to compensate, and based on your reaction, it must be well below 6800ft. The difference is bound to be greater in a N/A car though.
p3u
September 1st, 2009, 21:42
However, the difference is not nearly as stark with a well controlled turbo car like ours since the turbos will be asked to keep providing boost until the requested amount (I seem to recall the ECU is requesting absolute pressure, not relative pressure, otherwise, this would not be the case) is created. I suppose there must some altitude beyond which our turbos just can't create enough air volume to compensate, and based on your reaction, it must be well below 6800ft. The difference is bound to be greater in a N/A car though.

There is a sensor that measures absolute pressure, and it will call for the same amount of boost from that reading.

If I remember correctly, the RS6 is supposed to be able to have 100% power up to 5000ft. Not sure if that is the case, as the difference seems to be very noticeable. One thing for certain, turbo lag is almost gone while down here!

Also, an NA car will lose about 3% power for every 1k ft above sea level.
SAF
September 1st, 2009, 21:51
Are you staying on Mustang Island or N. Padre or are you actually in town?
p3u
September 1st, 2009, 21:55
Im about 30 min from Corpus Christi, in Kingsville. Im in town till Fri/Sat. Where about are you from here?
SAF
September 1st, 2009, 22:37
Should be some nice long open roads around Kingsville!
I'm up north of Houston, but Mustang Island has been my beach house getaway for 20 years. Nothing like 4 wheeling down 50 miles of National Seashore to get away from it all.
SAFE4NOW
September 1st, 2009, 22:38
Stop by and say hello if you are driving back through Dallas.. I'll buy lunch.

Steve
AudiRS4ever
September 2nd, 2009, 14:12
Stop by and say hello if you are driving back through Dallas.. I'll buy lunch.

Steve


Now that's crap. You never bought me lunch Steve. :cry:
SAF
September 2nd, 2009, 14:22
Must be a helluva lunch, because going through Dallas on the way to Colorado Springs from Corpus isn't even on the scenic route! ;)
SAFE4NOW
September 2nd, 2009, 16:49
Must be a helluva lunch, because going through Dallas on the way to Colorado Springs from Corpus isn't even on the scenic route! ;)

yea yea.... I was thinking Al Biernat's
http://www.albiernats.com/

Then maybe get the car on the Dyno for some numbers from " down here " closer to the water than CO.

Steve
:hihi:
SAF
September 2nd, 2009, 17:25
yea yea.... I was thinking Al Biernat's

mmm... Veal Osso Bucco. Wish I'd known, I was in Desoto this past weekend.
p3u
September 2nd, 2009, 17:38
Stop by and say hello if you are driving back through Dallas.. I'll buy lunch.

Steve

I may have to take you up on that if you're available this Friday or Saturday. Very kind of you to offer! It would make the trip more enjoyable to stop for a bit, rather then drive 15 hours straight again :hahahehe:

Any drag strips around the area by chance? :burnout:
DALLAS_RS6
September 2nd, 2009, 17:42
yea yea.... I was thinking Al Biernat's
http://www.albiernats.com/

Then maybe get the car on the Dyno for some numbers from " down here " closer to the water than CO.

Steve
:hihi:

Steve, let me if this happens. I would like to come over for this.
ben916
September 2nd, 2009, 17:53
Now that's crap. You never bought me lunch Steve. :cry:

me neither....
SAFE4NOW
September 2nd, 2009, 18:54
I may have to take you up on that if you're available this Friday or Saturday. Very kind of you to offer! It would make the trip more enjoyable to stop for a bit, rather then drive 15 hours straight again :hahahehe:

Any drag strips around the area by chance? :burnout:

1. You bet.
2. Texas Motorplex 1/4m , Redline 1/8m, and Denton Dragway 1/8m. Redline: http://www.redlineraceway.com/FridayBracket.htm

If the Dyno's are finished in time, we could always do a SIM 1/4m run for you... Just a thought...

Steve
SAFE4NOW
September 2nd, 2009, 18:56
Steve, let me if this happens. I would like to come over for this.

Noted sir!

The list:

1. SAFE4NOW
2. p3U
3. DALLAS_RS6
4.
5.
p3u
September 3rd, 2009, 00:35
It's looking like Friday will be the day I'm leaving, so as soon as I figure out when I'm leaving I'll let you know. How far away would you estimate?
SAFE4NOW
September 3rd, 2009, 03:49
It's looking like Friday will be the day I'm leaving, so as soon as I figure out when I'm leaving I'll let you know. How far away would you estimate?

5-6hours depending on police intervention IMO, you could make it faster, but I do not know your driving style and you don't know where the speed traps are.

Friday noted either way..

S
R1
September 3rd, 2009, 06:12
Now that's crap. You never bought me lunch Steve. :cry:

same here Steve did not buy me lunch when i visited last June :hihi: j/k :)
p3u
September 3rd, 2009, 19:12
5-6hours depending on police intervention IMO, you could make it faster, but I do not know your driving style and you don't know where the speed traps are.

Friday noted either way..

S

Could you PM me an address?

It's looking like it will be around 5 when I'll be in town.
DuckWingDuck
September 3rd, 2009, 22:36
be sure to snap some pics and take some video guys!
SAFE4NOW
September 3rd, 2009, 23:41
1. Everyone that says/said I owe them lunch, come on down! I will buy lunch on a SMD or Weekend Rs6 drive down in the Hill Country or at the State Audi meet 1/2010 !
2. We will take pixs, not often you get 3 Rs6's together at once...

Steve
DuckWingDuck
September 3rd, 2009, 23:50
heh.......
SAFE4NOW
September 5th, 2009, 01:05
Someone made it by today... a little Dyno time, then off to dinner:
SAFE4NOW
September 5th, 2009, 01:09
One more:
SAF
September 5th, 2009, 05:20
Nice. I need to get up that way again soon.
MarkusRS6
September 5th, 2009, 09:38
that cooling fan looks a bit small to me

how much was it pushing to the wheels?
SAFE4NOW
September 5th, 2009, 14:32
that cooling fan looks a bit small to me

how much was it pushing to the wheels?

I was thinking the same thing. We actually moved another one over, so they were side by side.

He drove right in after driving 6+ hours, the last part in traffic, numbers were low due to conditions.

S
MarkusRS6
September 5th, 2009, 21:21
how low?
SAFE4NOW
September 15th, 2009, 03:00
how low?

300's.... Sorry, I missed this post last week. We didn't save the numbers for obvious reasons...

Steve

p.s. Has anyone heard from John since he left Dallas? Just curious... I know he was driving straight through and left DFW around 8pm headed to Colorado?:incar::incar:
p3u
September 15th, 2009, 03:43
300's.... Sorry, I missed this post last week. We didn't save the numbers for obvious reasons...

Steve

p.s. Has anyone heard from John since he left Dallas? Just curious... I know he was driving straight through and left DFW around 8pm headed to Colorado?:incar::incar:

It was a rough week back....At least I'm in one piece! :)

http://www.rs6.com/forum/showthread.php?t=19288