jmk wrote:
: Right. A turbonormalized engine never sees any more pressure than one
: that is normally aspirated - it just sees it up to a high altitude.
: Cooling (at high altitudes) may be an issue, but not cylinder pressure.

Actually, technically speaking, running the same MP at higher altitudes will
produce a little more power than at lower altitudes. The lower ambient pressure
reduces backpressure on the exhaust, so there's more scavanging and a bigger intake
air/fuel charge for the same MP.

I saw that in the performance specs on a friend's normally-aspirated
PA-24-250. Something like equal power is between 1-2" different MP at 12000' vs. sea
level (RPM constant). I don't remember the exact numbers, but that's in the ballpark.

-Cory

--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
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