[T3] Re: Petrol octane

["Petri O. Calderon Larjanko" <petri@unsw.edu.au>]

> 
> Higher octane allows an engine to operate with higher compression ratios. If
> you use too low an octane you will get knock which is hard on an engine. Once
> you have the octane high enough that knock does not occur there is no
> additional benefit from higher octane.
> 
> In some cases using higher octane may allow you to run with more spark advance
> without knocking. This will generate more power, but the higher octane was not
> the real source of the power, it just allowed it to happen.
> 

Here in Australia we have Unleaded, Premium unleaded and Lead Replacement
(don't remember the octane levels).  The Lead Replacement Petrol (LRP) was
introduced when Leaded fuel was phased out.  I have heard reports that LRP
is not very good for our aircooled engines, so despite using it I have been
worried about it.  I have also read reports that an engine in good condition
(whatever this means) can use regular Unleaded with no problems.

Any ideas on this?

Petri
'71 Notch

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