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View Full Version : Altitude and your choices.



airpiraterob
05-01-2003, 12:54 AM
Curriosu about teh rocky mountain guys and the high altitude tracks out there. does this change your decisions about what to run in any way? Are certin engines able to withstand altitudes better than others in some way? ie: retain torque better? Technically i suppose they all loose power the same but im not totally sure. also, whats popular to run out that way anyway?

Knestis
05-01-2003, 10:20 AM
Not knowing any specifics and all other things being equal, I would opt for a more modern FI car rather than one with a carb or carbs. Seems likely that the range of conditions within which it will work reasonably well is greater.

We ran the Bogus Basin (Boise, ID) hillclimb one year and it was notable how much power the car (and driver!) lost at something approaching 7000 ft. I can imagine what it would be like running Pike's Peak.

K

ITANorm
05-06-2003, 12:44 PM
FI is definitely better, but you're still going to lose major amounts of power at altitude on any normally aspirated engine. It's simple physics, antd there just isn't any air to be had unless you pressurize the intake.

We ran the national circuit doing TSD rallies many years ago, and one event went over Mosquito Pass (+/- 11,000') in Colorado. My trusty fuel injected 22RE powered 4Runner would top out at about 4,000 RPM in 2nd climbing the 7% grades near the top.