Re: hotter plugs on hopped rebuild

["Bruce Plecan" <nacelp@bright.net>]

In a word, NO.
With the info., you've supplied, your just slightly hotter then stock, and
if anything you would venture to cooler not hotter plugs.  The hotter the
plug the more likely you are to have a detonation, problem.  The whole idea
is trying to keep the chamber cool other then at the moment of ignition.

  You have so much spark energy. Period.  You eat away at that jumping air
gaps.  Have a big enough air gap, and the spark won't even happen.
   You need to have enough energy in the spark to generate reliable
ignition.
   There is some (minor) advantage in huge air gaps, in that they get the
"fire" ball to a diameter of .10" faster.  With that you can decrease the
timing a couple degrees.  Trouble is the plugs don't last long, erode fast,
and are prone to misses.  In the 80s GM tried running .060" gaps and what a
huge waste of, time, effort, and money that was.
   Use the oem's for a while, and then READ THE PLUGS.
   Why the caps?.  This makes the 3,354,879,726,973 time I've said it, and
try reading tuning.doc at the FTP..
Grumpy



> I just had my LO5 TBI350 truck motor rebuilt. It was bored 30 over and now
> has a cam with 204/214 duration, 420/440 lift and separation of 110. The
AC
> Delco book list a plug of CR43TS with a gap of .035. I am wondering if
> moving to a CR45TS and widening the gap would be beneficial. .035 seems
> awfully tight for a HEI ignition. Anyone see a problem with the hotter
plug?
> Paul Washburn
> lpwcruzr@netzero.net


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