[T3] Ign Timing questions

[Chris Wright <Christopher.Wright@Sun.COM>]

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Dan,

Having had a load of problems with timing recently, I'd say that if it's 
now not pinking under any conditions, it's no longer too advanced.

Also, be careful with the advice you get, helpful folks advise from 
within the experience of their own car and dizzy and you'd have to have 
exactly the same setup for it to work for you.
As an example, On the 64 1500S distributor, (Vac and Centrifugal)  the 
advance curve starts very low at about 600-700rpm.  Therefore to use the 
middle mark when it's on tickover at 900rpm is wrong.   The middle mark 
is 10degrees advance and should be used to set it static or with the 
engine running at 6-700rpm, which means removing 2 opposite side plug 
leads to reduce speed while you set it.  Once you put them back and are 
ticking over at 900rpm again, you find the timing is now on the RH mark 
which is 12.5degrees.  Most people would advise that 12.5 degrees was 
too advanced if they didn't know the circumstances under which it was 
measured.

The one thing that everyone is agreed about is the 009.  These are 
notorious for variations in manufacture so you set them for max advance 
of 30-32degrees, (usually at around 3500+ rpm).  Ignore the urge to 
check them at tickover or static because this may show some significant 
variance from the 10 degrees you'd expect.

Someone sent me the exact measurement round the pulley for 30 degrees if 
you don't have an advanceable timing light.  I can dig this out if you 
need it.

I'd be worried fitting the wrong vac advance dizzy to my car because 
they should be matched to the vac take off from the carb and VW used 
different takeoffs and vac units in different dizzys.  ie the 
aftermarket dizzy you were looking at might be right for a T1 with a 
PICT 34 carb but you'd need to get it analysed to see if the advance was 
right for your T3.


Rgds Chris

> > Why can't you be sure? Was it because any change was just too small to be sure
> > of, or because other things got changed at the same time? Were you doing the
> > switch to synthetic at this same time?
>  

i changed the oil to synthetic, hoping to get the temps down.  then,
after doing the drive once and noticing that temps were up rather than
down and not wanting to do any damage, i checked the timing to see if
that was the culprit.  it was way off, like i said, so i changed it to
the middle timing mark.  i know the old adage about only changing one
thing at a time, but i figured it wasn't worth overheating an engine
to get the diagnostic info.

> From your note I wasn't able to discern what problem you hope to

> > address. Your timing was overadvanced, you changed it, the pinging went
>  

i heard that just because you can't hear the pinging doesn't mean that
it's gone and you could still be doing damage to the engine and not
even hear it rattling.  so, my questions are:

1. is the middle timing mark the correct one for my engine setup?

2. if i go by hearing a ping or not, am i retarded enough to be safe?

3. if i have to retard it any more and lose more power, should i just
go for the ACN SVDA dizzy because it will give me a more correct
timing curve and the best of both worlds, supposedly, with a good
advance curve.

thanks,
Dan
---------------------------------------------------------
Dan Hoopes
1967 Red Squareback "Stanley"
www.hoopes.net/dan/square/before.html

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