On Thu, 3 Feb 2005 14:22:05 -0800, "Chip Louie" <[EMAIL PROTECTED]> wrote/replied to:
>Actually increasing the octane level is used to delay the onset of >detonation or predetonation of fuel in the combustion chamber. Increasing >the octane number of gasoline ideally should not delay flame propagation in >the combustion chamber, only the point of uncontrolled detonation. Modern >combustion chamber designs and materials are much more tolerant of high >compression than the older, say 1995 and earlier designs. Almost all high >performance combustion chamber/piston designs are capable of between 1-1.5 >points higher compression ratio for a given octane number than these older >CC designs were capable of suppressing the onset of pre/detonation. > >I know something about engine management software. I taught Aaron Neumann >(one of the principals of the highly regarded company Neuspeed and APS the >distribution arm), how to modify the engine management programs in Bosch FI >systems over 14 years ago. Even way back then there was already a fall back >for low octane fuel in the engine management programs. This subroutine has >propagated to even the lowest level of automobile engine sold in the USA due >to emissions warranties here in the states. Totally offtopic, but modern high compression engines now use a detonation detector to avoid pinging with the low octane fuels used today. Basically the same device used on turbos. -- Jim Davis, Nature Photography, http://easternbeaver.com/ Motorcycle Relay Kits * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
