Ron,
Sounds like you did the right things. Static timing is a good place to
start. With 15 degrees initial and 15 degrees centrifigal (re-curved
dizzy) you are at 30 degrees total which should be fine. I would check
the timing and dwell with a timing light and dwell meter. Since you are
back to running points you may get soME more performance improvement by
getting the dwell spot on (hotter spark).
BTW with all this burned piston stuff I decided to double check my
timing. I put a 35 degree mark on the pully, hooked up the timing light
and ran the revs up to check max advance. Uh oh! 42+ advance. Then I
remember the vacuum advance is still hooked up -- duh. Rechecked with
vacuum advance plugged, 35 total (20 initial, 15 centrifical). Whew! I'm
running the B cam, and SUs on my U20. Runs great at still gets 25 mpg.
Todd Osborn
68 DATSFUN
Ron & Julie Edgar wrote:
> My 1600 by all viewable signs is in good running order. Compression is 185+
> in all cylinders. New head gasket, fuel pump, water pump, starter, ect.The
> internal parts such as timing chain, rocker arms ect can be viewed on my web
> page, all are clean. Engine could be a rebuild but not knowing the history
> of the car I do not know. The car does have headers and a new non-smog re-
> curved distributor.
>
> Car starts every time, hot or cold, by the second try with no choke. (never
> had one) Carbs are worn but they are running great at the moment. It did
> have electronic ignition up to a month or so ago but I pulled a stupid stunt
> and left the battery cable on while I was working on the carbs. (Note:
> always disconnect your battery when working on you car) I grounded out the
> starter lead with a wrench and it was a great fire works show. From that
> time on we started seeing performance go down hill. Wouldn't idle and seemed
> to be running on 3 cylinders. After trying different coils, ballast
> resisters,cleaning and adjusting the carbs I was still unhappy. So I finally
> got to looking at the distributor and decided to pull the CDI and restore
> the old points. Well it appears the voltage spike that scared me to death
> had found its way to the CDI and damaged it. Now with points the old girl
> came back to life and ran better but still not great. Then I got to
> thinking how we tuned up our motorcycles when I was younger. With a two
> wire test light. So I set the point gap, turned the engine until #1 was at
> TDC then carefully set the timming marks on 15 deg before TDC. I then placed
> the ground lead on my light on ground and held the hot lead on the points.
> I then slowly turned the distributor until the points turned on the light.
> I did this very carefully and locked the distributor down at just the point
> where the light came on. Well the car has improved so much in performance
> its hard to believe. But it didn't stop there I changed to Mobil 1 Oil and
> performance increased again.
> Still had a small idle problem and a friend suggested BOSCH Platinum plugs.
> Put them in and a now the I can see out my rear mirror at idle (1800
> rpm)Have been driving the car this way for over 6 weeks, taken a few 100
> mile trips. Cruise at 80 if I would let it. Have pushed it past 90. (for a
> short time) Car runs better then ever. Only draw back is in the morning I
> must let it hit 150 degrees temp before starting down the road. (remember
> no choke)
>
> So gurus :-) What have I done that's different and am I set up to burn a
> piston also?
> How do I know if I am too far advanced or too lean? I used 15deg to avoid
> being too advanced?
>
> Ron Edgar
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