After some work I did on my GT6 mk3, it's not running quite the same and
hopefully the net wisdom can help. Thanks in advance for any
suggestions.
Background:
The car was running fine, except for a noisey distributor. Found a
brand new Delco D204 on the list. My old one was also a D204, but the
new one has a different vacuum advance (actually retard) unit. Other
than the cam oiler, it seems to be identical. Installed the
distributor, set the points, idle and timing. Just then it started
idling at ~1500 rpm. Found the front carb needle had dropped it's
retaining clip, pulling the needle up. I had a set of performance
needles Apple had sent with the rebuilt carbs 2 years ago. figured this
was a good time to install them. Put them in, synced the carbs,
adjusted the mixture to a very light blue on the colortune. Seems like
I couldn't get it any richer than that. Took it for a test ride. Not
enough power starting from a dead stop and the top end doesn't seemm to
be there either. Also, ran pretty crappy when cold. Lots of carb
backfiring, ocassionally once it warmed up. Also when it (the engine)
would get hot, the idle would creep up to ~1800 rpm. Drove the car a
week to work like this.
Fast forward to this weekend. Time for the Pasatiempo meet (great time
but that's another story). Cleaned and gapped the plugs to 0.025",
they're running white/very light brown color. Re-adjusted the points
to ~0.016", and changed the timing with the vacuum unit hooked up from
4 ATDC to TDC. Dwell reads 32 degrees, should be 42?? The car runs
noticebly better, but it still lacks the power it should have when
starting from a dead stop and the top end isn't like it was. Also, it
still sometimes idles really high when it gets hot (during the run this
happened, engine temp between 3/4 mark and red).
Any suggestions?? From reading the Haynes manual, the vacuum unit
actually retards the timing and timing advance is done mechanically.
I've read some of the thread on the TR6 timing issue. Is there a
better way to time it than dynamically at idle? I'm also wondering if
the distributor is that much different than the old one to cause these
problems. Or could it be the cahnges I made in the carbs?
Thanks,
Mike
(lots of questions, but no answers :^(
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