Emery,
Dunno about the misprint. I know what
I did. Also I'll get you that P/N for
the 15 Hg advance mechanism. I posted it
about 2 weeks ago and haven't been out
to the "Sweat Lodge" to get that for you
but I will this weekend. I know my base
is now set at 12-13 degrees advanced and
seems to do pretty well. The EKE works
only when needed and overall I am
satisfied.
Amazing what an impact that the base
timing, springs and vacuum advance all
make individually to the timing as a
whole which translates to performance
and economy. Change one and it moves
everything around. Where it might have
been pinging at low end with a slight
adjustment now pings at midrange or if
you're real lucky not at all! Sometimes
I'm best off to make a chart of what
I've changed and what impact it's made.
Then after road tests and later over a
beer or two I can evaluate the situation
to see if I'm really where I want to be.
I wound up at a base of 12+ degrees,
medium springs and a 15 Hg advance
mechanism. Don't forget the Caspro EKE
too. Probably not for everyone but with
the Caspro engine it works well for me.
Nate '75GB (Doesn't know if it wants to
rain here or not) Omaha
>
Date: Thu, 22 Jun 2000 18:58:12 -0600
From: "Emery L. Stora"
Subject: GMC: Vacuum advance
A couple of days ago I had posted that
the 1975-76 Maintenance Manual
and the 77-78 Supplement show the same
vacuum advance control 1973523
for the 1975-76 and the 1977
non-California 455 engine but the max
advance is shown as 12 degrees for the
75=76 and as 24 for the 1977.
Is this a misprint? Does any know the
correct amounts? Should it be
12?
Anyone have an answer to this?
Emery Stora
77 Kingsley
Santa Fe, NM
