Hi all!
I've finally finished my engine rebuild, except for the fine tuning. But
it's nice to hear it run without that "knock knock" noise! Anyway it
seemed to have a pretty weak spark, so I started checking and the point
gap was way off, so fixing that should help.
My confusion is related to the vacuum advance though. The distributor is
a 25D, model 41271. No according to the chart on Paul Tegler's page
(http://www.teglerizer.com/mgstuff/advance_curves.htm) this thing should
be getting it's vacuum from the carb. The car had a really weird
homebrew setup with a single barrel carter on it when I got it and I
converted back to SUs. I can't remember exactly what AUD# the carbs are,
but I do recall they match the #s given at Burlen Fuel systems for a
1971 Midget, so I thought they were right. They have the connections for
the crankcase ventilation, but not for the vacuum advance so I
unknowingly connected the advance to the manifold. I thought there was a
problem though since at idle it seems to be fully advanced, and when you
shut it off after a second or two you can hear the advance release where
it was pulled back so hard it was slightly stuck.
So what to do? I really don't want to replace the carbs! Should be
looking for another distributor that works off the manifold vacuum, or
just swap advance units with one one that does? As long as I match the
vacuum source to the advance unit, does it otherwise matter? The engine
is mostly stock - only changes are 030 over and a Kent 256 cam.
Somewhere (Minimania, perhaps?) I've seen one of those phenolic carb
spacers with a vacuum port. Maybe look for one of those?
Thanks for any suggestions!
Eddie
1971 Midget - Bebop
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