DeTomaso Mailing List: March 2000, Message #144

Glidden was a drag racer. Engines can stand quite a lot more spark advance in 
a very short acceleration contest than they can after a few more minutes of 
running. Sure, in a cold engine with a radical cam, with 108-octane fuel, in 
a drag race, extra spark sometimes makes the engine feel like it's snappier. 
But experience has shown that on the street with a hot engine, you WILL 
detonate a hole thru a piston running more than about 38 degrees of total 
spark, and with the 87 octane weed-killer now sold in CA as 'gas', I wouldn't 
go over 36. I remember a chassis dyno run on Mike Drew's Mustang 302 in which 
the hot engine made MORE power with 32 degrees total spark lead than it did 
with the 36 he drove in on.  Total spark lead is a measure of combustion 
chamber efficiency and the burn speed of the fuel. My 2¢- J DeRyke