My impression has always been that the MSD et al would give power gains
only if the "stock" ignition was in trouble for whatever reason. If normal
points/coil ignition could get the fire lit, and the combustion parameters
allowed reasonable burn, then the MSD wouldn't do better than that for
you. But if you were over the edge in your motor for whatever reason (18:1
C/R in a Winston Cup restrictor plate motor of a few years ago leaps to
mind, as do some early 4 valve race motors that had truly crappy
combustion) then the added voltage potential and multiple sparks of the MSD
could get you out of trouble.
Said another way, perhaps the MSD could allow you to design and build a
motor that wouldn't run well using points/coil ignition. But if you do
build a motor that runs well on points and coil, then the MSD wouldn't help.
Since MSD isn't allowed in our club, I never actually tried one. It would
probably help in my Martin engine - that is a three valve head with two
intake valves. The design has no swirl in the combustion chamber and a
very big flat chamber with virtually no squish - and the recommended timing
is 48 deg BTDC. I never tried over 44 deg, and we had to run it very
rich. That motor ran perhaps 30 - 40 degrees hotter than the 1600
cross-flow that I now run. The interesting thing is that the pistons came
out absolutely clean and shiny - almost zero carbon buildup. I took that
as an indication that it was running pretty close to detonation.
brian
At 09:23 AM 7/6/01 -0400, Phil Babcock wrote:
>Jack
>
>Contrary to claims but manf. & magazines we have not seen a single gain
>on any car before / after. Six changes were done while still strapped to
>the Dyno in our shop.(fairly stock engines) In fact on my Lotus I
>actually lost 2 HP, when I called MSD at first they tried to give me the
>runaround, then when they realized that I owned a Dyno, wanted to use the
>MSD (really for the soft touch rev limiter) they gave me a guy, who
>suggested changing the timing and jetting. I did so and was back to where
>I started.
>
>However, I think the car starts easer, and it would seem is a little more
>responsive. If one had an engine "balls out" with very high compression,
>I am sure there would be some gain, due to possible flame blowing BUT I
>have not seen the gain in here. All the really balls out cars already
>have them installed.
>
>Hope this helps
>Phil
>
>"Jack W. Drews" wrote:
>
> > Haas anyone seen actual dyno results of an engine with and without an
> > MSD ignition?
> >
> > --
> >
> > uncle jack and New Blue
>
>--
>Phil Babcock
>The Dyno Shop, Inc.
>Air Fuel Ratio Meters - Laser Alignment Tools - Dynojet Chassis Dyno
>Race Set up - Auto Restoration
>http://www.thedynoshop.net
>mailto:phillipbabcock@att.net
Brian Evans
Director, Canada
MCI Wholesale Internet Services
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