bhp

[Jeffrey Engel]

> 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
> 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 :)
> > 
> The spark energy influences the power (by increasing the burn rate) more
> than the spark plug itself, and this is related to the stored coil
> energy and not necessarily the plug specification. 
> 
> 50 hp sounds like a lot, but if you've got a 2000 hp Merlin XX then it
> seems feasible.  In the real (automotive) world, you might see a 2-3%
> change.
> 
> Andrew Rabbitt 
> 
Sometimes something a lot less awesome than a Merlin.  Several 
thousand miles ago I changed from Bosch Platinum plugs to Motorcraft. 

My 2.3l Turbo Coupe motor LOVED 'em!  I must have picked up 25 hp.  
My guess is that the Bosch plugs were misfiring enough to screw up my 
a/f ratios but not enough to detect in the seat-o-pants dyno.  

Cumulative effects like that could add up to 50 hp quickly.   I'm 
thinking 5 liter and a paxton-type supercharger.

je
jengel at fastlane.net

     "I can resist anything but temptation"
                                  Mark Twain