McGG

Here in Calgary, the air is relatively thin. From what I've read, this can have a serious impact on power in a normally aspirated car.

Both of my current vehicles are turbo-powered, so this is less of a concern. (although I anticipate that the turbos work harder at altitude).

Anyone else have a C63 at altitude that can comment? I'd hate to pay the money, and effort to get a C63, and then find out I'm getting far less than 400hp from the motor.

Turbo-charged cars appear to represent a better value across the board, than big displacement cars here.

(Maybe I should wait for the C class that has the V8-TT).

rage2

Calgarian here. The C63 is much faster in Vancouver at sea level. With P31 or chipped you're getting about 400hp in Calgary. My 420hp 996TT is slightly faster here.

With that being said, the C63 is much more fun to drive. Instant torque with zero lag. Turbo cars here can make the same power, but it gets much laggier here too. So choose what's more important.

With traction probs in the first 2 gears, you're only going to lose out at the drag strip. Since we lost our track this winter, the choice should be obvious.

Merc63

FI car still looses power as elevation increases (absolute pressure) but not as much as an NA car. Turbo has to work harder so lag increases with elevation like rage2 said.

I wouldn't worry about it. Edmonton here

McGG

If I'm not mistaken, the P31 actually is under-rated and makes more like 500+ hp at the crank?

So it's down almost 100hp here? Yikes!

Still, the feel is probably still there....

GeorgeSmooth

I am at 5500ft altitude. The C63's normally make in the region of 310whp up here. So the losses are great the higher you go. Rule of thumb at my altitude is a 17% loss on average.

Sher Judge

Where I live, its about 1600 meters or more above Sea Level, yes a naturally aspirated engine does suffer, but only a small percentage.

Obviously on a really hot day you will be out gunned by a turbo or charged motor.

Multispeed

I am in Calgary and central Alberta as well. Remember that one of the few good things about winter below zero temps is the cars, etc. start running pretty good. I think the car runs the strongest around -20 to -25 C. Freezing my *** off but the car sure rocks! Colder than -30 and the whole thing just feels stiff.
Then every spring you can feel it get wimpy and on a hot summer day you dont even want to drive it.
And of course the other good thing about winter is the slippery roads. You can drift to your hearts content and it easier on the car doing it on slippery roads.
We get to drive like the road test guy who put those skinny tires on the C63, but for at least a third of the year! Calgary aint so bad!

GeorgeSmooth

Did a run today. 70% humidity at 32 degrees celsius ambient. 5600ft altitude.

C63newdude

You are going to lose power no matter what. It doesn't matter what engine powerplant you use (I owned 18 Turbo cars and I live in altitude).
I go to mount Lemmon in AZ and at 9000 ft you can tell the powerloss too.

If your main concern is losing power then you don't have the right mind set. Every neighboor that lives near you has a car that also loses power to altitude. I live in some altitude and summers here rob a lot of power to ALL my cars.

I couldn't do much to my previous turbo cars because the 115 degree heat will cause knock on the engine. I could run about 3-4 PSI less on my turbo cars in the Summer than in the winter when the temps were in the high 20-low 30's. The only thing that I have done to some of my previous turbos cars(Evos and Eclipses mainly) has been running them with alcohol/methanol injection and also having them tune for E-85.
If I were you I would just forget about that psychological barrier that you are creating.

C63newdude

I always heard that it is about 10% of power loss every 1000 meters but who knows. All that I can tell is that US the people that live in altitude are use to.

C63newdude

+1. You can also tell that the BOV makes more nosie and takes longer to open and close. Turbos has to work harder and if you have an older turbo car that don't have a boost controlling mechanism you can also lose power.