Although many people use this method I have a good publication from Repco,
of Repco Brabham fame, which suggests that this is not too wise as the over
advance may not be apparent and can cause crankshaft fatigue cracking among
other things.
Having experienced a broken crank I am a little cautious.
With a Healey 6 cyl setting the timing to 5/8" BTDC static is pretty safe;
presuming of course that the distributor centrifugal advance system is
operating correctly.
Michael Salter
www.precisionsportscar.com
-----Original Message-----
From: owner-healeys@autox.team.net [mailto:owner-healeys@autox.team.net] On
Behalf Of John Miller
Sent: Sunday, May 29, 2005 5:35 PM
To: Healey List
Subject: Re: advance ignition timing 3000 MK1
tnewton wrote:
> I am sure this has been covered to death over time, but could some one
please
> confirm a couple of details regarding ignition timing. What is the general
> consensus on how much advance seems to be best, and from the TDC timing
mark
> on the pulley how many millimetres per degree (in other words what is the
> circumference of the pulley divided by 360.
> Although my car engine seems to like the present setting, when I checked
the
> setting it measures at least one inch (25mm) advanced from TDC - I don't
know
> what this would be in degrees but I suspect this is a very advanced level?
Please don't take this as gospel, but just another data point: with an
engine of this vintage, provided the vacuum and centrifugal advances are
working, the correct timing is the point at which you can just get it to
ping under extreme load (typically lugged down beyond the point at which
you would reasonably operate the engine). To put it another way, if you
set the timing to spec with a light, and the engine either pings
excessively or you can't get it to ping under any circumstances, then
you might want to consider adjusting the timing away from "spec."
--
John Miller
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