octane and other additives, was : IML: 100 octane in a 58 Imp????

["D. Dardalis" <dardal@xxxxxxxxxxxxxxx>]

At 01:26 PM 2/26/2002 -0500, you wrote:
>Thanks for the info.  The additives I was referring to were to compensate 
>for the lead that has been removed from modern gasoline.  I had a 71 caddy 
>and ended up with a burnt valve in 91 because I didn't compensate for the 
>missing lead.  I will spend the addition for higher octane fuel because I 
>feel that the engine will cleaner in the long run, and since I don't use 
>my cars as daily drivers it isn't that  much extra.
>Bob Becker

  Lead in gasoline had two separate functions.  One, was an inexpensive 
additive to raise octane number of the fuel, and Two, was lubricate the red 
hot exhaust valve.  Now, lead additives have been replaced with other more 
expensive additives to raise the octane, but unfortunately, these do not 
have the lubricating abilities of the tetraethyl lead.  So, running higher 
octane fuel than your engine need does not really offer any added exhaust 
valve protection...
D^2