On 10 March 2010 16:30, zMan <[email protected]> wrote: > > On Wed, Mar 10, 2010 at 4:11 PM, Rick Fochtman <[email protected]> wrote: > > > Not so much high-horsepower engines, but rather high-compression engines. > > Makes a HUGE difference in aircraft reciprocating engines. Higher > > compression leads to higher heat buildup in the cylinder and that can lead > > to pre-ignition, with seriously detrimental effect on the engine and the > > power curve. Higher octane fuels reduce the pre-ignition problems. > > > > Note that the distinction here is between *controlled combustion* and > *detonation*, which is uncontrolled combustion and can cost you cylinder > heads, blocks, valves, etc. Not a good thing. > > Are we far enough OT yet?
We could bring up Diesel engines, with their very high compression ratio (23.5:1 on my old Rabbit), and speculate on why they are almost unheard of as aircraft power plants. But it's not Friday yet, so I won't. Tony H. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
