Basic principle for timing - as far advanced as you can get it (with the
fuel you usually use) without the engine pinking (or pinging, as it's called
in the US).
Go for a run. With the engine warmed up, floor the accelerator in a high
gear with low revs (around 1500-2000rpm). Do you get a somewhat diesely
knocking noise? If not, try advancing the timing a little. Repeat test,
advance some more, until you do get pinking. Then back the timing off
slightly.
Using a higher octane fuel will allow you to have more advance, but if you
then change to a lower-grade fuel you may start pinking.
Modern electronic ignition systems do this in a more clever way. They have
a "knock sensor", and will constantly advance the timing until the engine is
on the verge of knocking. This way, you can stick any old fuel in a modern
car and it will automatically adjust the timing to get the best out of the
fuel. Note - this applies to modern engines with complete engine control
systems, not to an old Triumph with a Pertronix conversion!
Correct timing should help fuel economy, at least a bit. It's also
important to get timing right before you start mucking about with carbs.
Oh, and before you start fine-tuning your ajustment, check that the system
is operating as it should do. Check the points gap. Detach the vacuum tube
from the manifold and suck on it, you should see the plate rotate. Smear
some vaseline on the distributor cam to lubricate it. Check the condition
of the distributor cap (should have no cracks). Check the condition of the
spark plugs, check the spark plug gap (you'll need a feeler gauge, I'm
afraid I can't remember the correct gap off the top of my head). Borrow or
buy (they aren't too expensive) a timing light, use it to get the initial
timing setting, and make sure that the timing advances as the revs rise.
Hope that helps!!
Richard
On 25 April 2010 23:32, Ryan <s1500@comcast.net> wrote:
> With the Spit out and such, I'm getting horrible fuel economy with my DGV.
> I even set the fuel pressure regulator to 2.0 lbs. Next step: Adjusting the
> timing.
>
> Is there a good web page, etc to do timing adjustments for dummies? I've
> never done it before. If the timing changes doesn't work, I'm considering
> switching to an electric fuel pump.
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