Hello Lance!
On 22 Apr 95, Lance Maresh hammered on the keyboard to James Dixon:
 LM> The only time you run into problems with an ABC engine and nitro
 LM> is when you break it in on low % and then later try to run it on
 LM> hi%. If you break it in on 30% and then later want to run 20 or
 LM> 15% you shouldn't have any problems, as a matter of fact if the
 LM> engine is getting tired and has been running 30% you may find a
 LM> bit more life in it by going to a lower % nitro fuel.
It's the other way around.  As you increase the nitro content, the
cylinder temperature rises, causing more expansion of the piston,
which generally expands more than the sleeve and case.
You can 'breath new life' into a tired ABC by going from 10% to 15%,
but not the other way around.
C-ya! Rich
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