Mighty Shilling

Well, using my Gtech pro SS, I did a run last time in California, and one here... and a Dynojet in Mansfield, Ohio...944fest last year (2005)

Well, there was a very significant loss in horsepower a mile above sea level...

Test car: 1987 924S (N/A)

Sea level (approx. 30 feet above sea level): 138 HP, 129 ft-lbs... (approx.)

Mansfield Ohio (approx 1242 feet above sea level): 123.6 hp, 122 ft-lbs

Denver, Colorado (5280 feet above sea level): 98 hp, 94 ft-lbs

I was shocked at how low the HP rating was up here... the tests with the Gtech were run multiple times... and I did test it on a drag strip (here) so I know the times were accurate.

I can post the graphs later if anyone wants to see what the Gtech pulled...

theedge

Yup thats normal....

Ooooo double digits, everyone get out of Porschephile's way!!!!

Mighty Shilling

hey now!

Mighty Shilling

note: I knew there was a huge loss... didn't know it was THAT huge...

xsboost90

thats why the computer is adjustable- to compensate for elevation changes. Where was your car purchased? it could prob. be adjusted out on the ecm back to normal.

theedge

Adjustment only takes care of the fuel.

Theres less power because the air is thinner = less air getting into the engine.

M758

comparing G-tech number to dyno number is kind of wackly. 138 hp is alot for an NA, too much considering the 129lbs of torque. 123 is what I would expect from an 87 with a cat. Phx is about 1200 feet so this matches up. 98 hp at 5200? Well again was that a g-tech run. I would not trust that. Also most dyno's are calibrated to correct runs to seal level and SAE temp so on dyno the corrected numbers SHOULD be the same at any temp and elevation. At least that is the idea for corrected numbers.

xsboost90

according to the diagram for the adjustment, it takes car of advance of ignition, as well as fuel. The whole reason for this switch was elevation.

Serge944

Yeah, there is nothing you can do about it. Air pressure is 1 bar and there is less oxygen by volume. Internal Conbustion engines are SOL at elevation.

CO951

Get some boost, you won't lose as much power.

Mighty Shilling

it's a colorado car... moved to Montana for a bit... back to Colorado...

Mighty Shilling

LOL... yes, I know... boost = not as much loss of power... but hey... can't really afford it.

docwyte

General rule of thumb is you'll lose 3% per 1000 feet above sea level on a NA car.

Rock

You ever been ontop a high *** mountain. Well I havent. But i heard its harder to breath, as the air is less dense and ****.