The 35 comes from trial and error, more advance and it pings too much, less
advance and it wants to run on. It will still ping a little under WOT at
heavy load but when the head was off I saw no sign of detonation. At one
point I had an MSD unit with an in-car timing adjustment knob. I could vary
the timing by a total of 15 degrees (+/- 7 degrees from the physical (dizzy
position) timing) and played with this until I got what I thought was the
best over all performance. At that point it was running at 35 degrees total
advance verified with an adjustable timing light. After the MSD was removed
(it broke) I set the timing to 35 degrees total advance and left it there.
Most of the oil is being burned. It drips a little but not a significant
amount.
I add an octane booster that helps some. Mostly I back off and downshift
when my ping detector says "It's pinging".
I do need to get the tools to do a leakdown test.
Larry Miller
----- Original Message -----
From "Robert E. Shlafer" <pilotrob at webtv.net>
To: "Larry & Sandi Miller" <millerls@ado13.com>; "Bugeye"
<bugeye@yahoogroups.com>; "Spridget" <spridgets@autox.team.net>
Sent: Tuesday, June 28, 2005 5:55 PM
Subject: Re: Engine Smoke Question
> Larry...
>
> I like your compression #'s....I bet it goes
> like hell! :):)
>
> Ass-u-me(ing) you are using a 20/50 NON-
> synthetic oil, the difference between wet and dry compression figures MAY
> be the
> answer to a quart every 400 miles despite
> excellent engine performance.
>
> A leakdown check may help to confirm how
> much compression may be escaping and
> most importantly, the source of same (valves or rings).
>
> With such high compression, whatever
> oil is getting into the combustion process
> is obviously getting pretty much burned off
> rather than escaping as "blue" smoke except during the (relatively)
> "cooler" periods of deceleration.
>
> Of course we are ass-u-me(ing) you are
> "using" it rather than "losing" (leaking) it? :)
>
> Incidentally, where did you come up with
> a total advance of 35 degrees at 12.0-1
> using today's "garbage" octane premiums?
>
> Sounds like a little much even with the
> cooler running alum. head. You using a mix
> of unleaded pump premium and racing
> octanes (CAM2, Turboblue, etc.)?
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