Sean Johnson wrote:
>
> Continuing in the effort to get my Spit to run right:
>
> I'm dealing with the question of static timing an engine. I'd be grateful if
> someone out there who truly understands timing could answer a question or
> two.
>
> First, the Haynes manual says that static timing "isn't practical" for
> electronic ignition engines. Any idea why this would be true?
>
> Second. The older engines are about 10 degrees BTDC, static or dynamic. The
> newer are about 2 degrees ATDC. Does the timing between the pistons and
> valves allow either of these settings, or were the respective engines set
> differently?
>
> any help gratefully accepted.
>
> Sean Johnson
> '75 Spitfire, '79 engine, HS 2's
Sean-
The cams were possibly a little different in these engines. But the
main reason for the timing difference is that the older engines were
timed with the vacuum advance disconnnected from the distributor and
capped. The later engines had a vacuum RETARD distributor and the
timing was set with the vacuum ATTACHED. If you capped the retard, you
will find the reading close to the 10 BTDC of the advance type. Be
careful not to get the timing out of spec on a catalytic converter
model, or you can run too rich and burn up the cat and the car. That's
why they are call Spitfire.
Brian
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