Steve,
You mention recurving the distributor. I'd work on the timing issues as well
as looking at the mixture. Sounds like the timing's getting advanced too far
too soon, particularly if it's pinging in city driving. Gary certainly seems
to have a handle on what these cars like.
I know that on the larger custom L-Series 4 cylinder motors, usually built
by starting with either a Z-20 or Z-22 bottom end and adapting a small
chamber/large port L-series SSS head, like a big chunk (15 degrees) of
initial advance, then less advance curve and total advance in the 27 to 28
degree range. That's quite a bit less than the 32 to 35 degrees that the
stock L-16/L-18 use.
Having said that, Happy Thanksgiving to everyone. While waiting for our son
to arrive from Fort Worth with the grandkids, I'm dumping the original 16
episodes of American Muscle Car being aired on Speed TV directly into my
computer. Then I'll cut out the commercials. It's fun to have toys like this
to play with.
Happy Holidays everyone,
Ron
>Fred:
> The mixture is set by adjusting the mixture nuts on the bottom of the carb.
> The needle determines the mixture profile. That is, mixture at different
> carb openings. Don't mess with the fuel pressure. They are designed to
> operate at 3.5 pounds (more or less).
>
> Defiantly sounds like you are running lean. Not a good thing at all. Too
> lean raises chamber temperatures and does all kinds of nasty things to your
> engine. Either learn to set them yourself or find someone who can. Running
> lean is bad news.
>
> Here are a few links that you can take a look at regarding the care and
> feeding of SU's.
>
> http://www.team.net/www/morgan/tech/tuning.html
> http://web.tiscali.it/no-redirect-tiscali/abosco/moto/carb/su2.html
> http://www.jetlink.net/~okayfine/su/sumain.html
>>Steve:
>> I tend to run with a little choke when city driving. Helps keep the
> >pinging
>> to a minimum when accelerating. I imagine I'm running a little lean, but
> >I
>> hesitant to start messing with a carb that runs well otherwise. Any other
>> way of richening the mixture w/o changing needles? Higher fuel pressure
>> perhaps? I've tried recurving the distributor and various timing
> >settings,
>> but it looks like Boone's elect dizzy may be the cure. I do notice that I
>> can chirp the tires from a start with the choke on, but not off.
>> Steve
>> 70' 1600
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