bhp

[Tom Cloud]

From: Andrew Rabbitt <AERabbitt at rce.ricardo.com>
To: "'diy_efi at coulomb.eng.ohio-state.edu'"
	 <diy_efi at coulomb.eng.ohio-state.edu>
Subject: RE: bhp
Date: Wed, 11 Jun 1997 08:51:01 +0100
Sender: owner-diy_efi at coulomb.eng.ohio-state.edu
Precedence: bulk
Reply-To: diy_efi at coulomb.eng.ohio-state.edu


> > Can you imagine how out of tune an auto would have to be for ANY
> spark
> > plug change to give an additional 50 Horsepower?
> 
> The purpose of the plug is to ignite the fuel.  In some circumstances,
> 
> different materials are more or less prone to oxidation in heated 
> environments, so yes, in theory, different plugs might make a
> difference. 
>  Also, plugs come in temperature ranges, different gap settings,
> different 
> insulator materials.  I've honestly never figured out technically the 
> reasons why, but if someone on the list can explain why a plug is not
> a plug, I'm all ears :)

aside from the obvious necessity for an insulator to force
the spark to jump a gap rather than taking a resistive path
to ground (which includes the insulator getting hot enough
to burn off any crud deposited on it -- but not too hot  :-)
 ... some electrodes for the spark to jump between; a
terminal to connect the plug wire too; and a good compression
seal, I can't see much either.  However, things like the
quality of workmanship and of the materials used, plus the
care in controlling the heat range, plus the type of materials
chosen for the electrodes so they don't corrode in the combustion
chamber environment -- seems there's definitely the possibility
of good and bad plugs.  What's being said (I think) is that
there's an awful lot of hype (lies) about plugs.  Actually,
there's hype in every area, not just automotive -- seems
you and I discussed your former employer (or do you just own
their stock) who specializes in selling **cheap** electronic
parts and equipment to unsuspecting, trusting novices  8-0

Tom Cloud <cloud at peaches.ph.utexas.edu>