Alan :
IMO, an IC engine is (slightly) less likely to knock at high altitude,
because of lower cylinder pressures. The reduction in ambient air pressure
has the same effect as reducing the CR. Same for fuel injection, and
regardless of mixture. The engine also makes less power, for the same
reason.
Randall
On Monday, March 15, 1999 5:11 PM, Alan Myers [SMTP:reagntsj@ricochet.net]
wrote:
>
> Listerati,
>
> Ok. I am not an engineer. Ergo, when these discussions get into
> exponentials and laminar flows, this red haze starts to descend on my
> vision.
>
> So I have a PDQ (probably dumb question) regarding altitude above sea
> level, please be kind and only mildly scientific in any responses.
>
> Everything else being equal, is a carburated car more or less likely to
> knock (or ping) as a factor of octane at high altitude, as opposed to
> sea level? Or, is this a neutral consideration, with leanness and
> richness of the mixture being the primary (or only) variable with
> altitude due to the difference in air density?
>
> Alan Myers
> San Jose, Calif. (sea level + 50 ft)
> formerly of Colorado (sea level + 6000 ft)
> '62 TR4 CT17602L
>
>
> --
> MZ?
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