<p class="MsoNormal" style="MARGIN: 0in 0in 0pt">I live at an altitude of 7000’. Does the Porsche engine management system help compensate for the difference from sea level or am I destined to enjoy less horsepower than you all at lower altitudes?
I used to live in Denver. HP loss up there was 10-15%. At 7000ft I would think you would lose 15%+. You need turbo to hang on to your HP up there.
The electronic fuel injection system will compensate the fuel/air mixture to correct for your density altitude. However, the reduced pressure and oxygen molecules/volume will still take it's toll on your HP. Need to go to turbo or supercharger (best route with space available) to get back the HP lost. /fckeditor/editor/images/smiley/MWPX/drive.gif
Right, it will compensate and correct the fuel/air ratio, but you've got less air. Like a negative turbo, so every engine makes less power.
I used to live at 7,200 feet and ran a few miles every day. When I would visit sea level and run my lungs gave me no indication that I was working out. My car had the same experience. Just one more reason for Santa Fe to visit Santa Barbara and Monterey, so that he can experience all 295 horses in the Cayman S.
The approximate correction factor is 3% per 1000 ft of elevation for naturally aspirated vehicles. Therefore, at 7000 ft. elevation, you will have an approximate 21% reduction in power.
If you want that 21% back, you either need to move or fit the car with some variety of forced induction.
Oh No that's not good news. That means that I am looking at a 12% (35.4Hp) loss, at 4k elevation. Maybe I can make it up on the long open hwy runs???? Guess engine mods are in the future here.
I believe the correction factor is closer to 4% per 1,000 ft. Here is a calculator with additional variables to get the exact loss:
http://wahiduddin.net/calc/calc_hp.htm
BTW, turbos are a great tool for altitude compensation, but superchargers are lousy. Unless you modify the pulley, you will suffer the same percentagealtitude loss as a n/a car. And if you alter the pulley to achieve 100% power at altitude, you will again lose power if you drive to a higher altitude and you will risk detonation and engine destruction if you drive to sea level, unless you first change the pulley back to stock. A turbo car has self-regulation by means of a wastegate, so that you never overboost. And, as long as the turbo is efficient enough, you can always make full power up to rather high altitudes (this is why airplanes use them).
Edited by - grant on 12/15/2005 12:11:04 AM
Edited by - grant on 12/15/2005 12:12:07 AM
