O Listers (wiser than I)
On behalf of a net-imparied gent in our club who lives mere blocks away, I
did a cursory "tune up" on his 70 spit 1300, single carb. The motor has
maybe 2k since a full bearings-up rebuild.
One of the local Austin Healey guys opened the idle trimming screw on the
temp compensator (big brass one) and the idle was shite afterward. So much
for AH drivers (never had strombergs, anyway). I set the carb correctly
(piston test and idle speed) resulting in a somewhat splashy misfire
(slightly lean without air cleaner). The car drives well (for a 1300) but
is still "lacking something". I found this upon further investigation:
the car has a Delco CCW rotation distributor with a vacuum ADVANCE mechanism
and adjuster (like the 22d4 Lucas adjuster).
The car has only ONE vacuum port, which apparently communicates with the
carb, not the manifold vacuum. There is no vacuum signal at idle, and, on
rev up, there is about 10 in. hg.
@#$#@$%@^, what's up with that?!?!? Jim swears that nothing has been
changed, but as far as I can see, he has an emission carb setup desiring a
vacuum retard, but with a vacuum advance distributor. Let's not even start
about the actual ignition timing...
Any brilliant minds out there seen this on a Spitty and resolved it?
Dave T
PS: Jim also has a 2 x 1.25" SU setup (you know what I told him to do
immediately)
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