Gads Spark attack-decay

Andrew W. Macfadyen am018 at post.almac.co.uk
Sun May 31 10:32:09 GMT 1998


I favour a  basic approach if an engine is so sensitive to ignition advance
that 1 or 2 degres make a big difference in  bhp surely something is wrong
with either the combustion chamber design or  a localised hot spot exists.

PS. As an old  CCC reader  I belong to the David Vizard school  rather than
the Dave  Waker followers :-)

Robert Humphris wrote:

> The words that Dr. Pelican writes are similar to the Technical Editor of
> ( in my sad worthless opinion ) the UK's best tuning magazine: Cars and
> Car Conversions.  Dave Walker ( for that is his name ) reckons that the
> optimum set up is to run as little advance as gives the best power, eg
> not on the verge or pinking... why?  if you set it up on the limit you
> can find yourself over it in no time, environmental temperature
> increases, crap fuel, various odds and ends can push you over into the
> land of Pinking... and we don't like to live there do we?
>
> Rob
>
> >----------
> >From:  Bruce Plecan[SMTP:nacelp at bright.net]
> >Sent:  21 May 1998 13:39
> >To:    diy_efi at efi332.eng.ohio-state.edu
> >Subject:       Re: Gads Spark attack-decay
> >
> >From: Chris Conlon <synchris at ricochet.net>
> >Subject: RE: Gads Spark attack-decay
> >>
> >>Should I take it as given that you get maximum power with maximum
> >>spark advance, just short of ping? Not trying to stir up trouble, or
> >>asking for God's Word on stone, just wondering. It *seems* like it
> >>should be so, but what do I know? (And how about advance vs. emissions?)
> >>
> >>   Chris C.
> >>
> >Seems to be two schools of thought on this.  Some want to run at
> >the verge of "ping", and my personal favorite, is as little as possible
> >consentant with best torque.  First one is easy to tune to the second
> >much more time consuming.........
> >  I beleive a safe statement would be as you recover more power from
> >burning a mixture NOX raises.
> >  Next the more fuel you burn CO raises (ignoring lean misses).
> >  Next the better you burn the fuel drops HC....
> >Please feel free to use the word react in lieu of burn.
> >Let's see how this flies..
> >Cheers
> >Bruce
> >
> >






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