Charles
Excellent reply from Mark, but if the springs and weights in the distributor
haven't been touched, they should be correct for the average engine (note
the key words "should be" and "average"). Here is how I have timed my 1275
engined cars for years.
Too far advanced causes the following problems:
Engine hard to turn over.
Engine idles too fast even with carb idle screw all the way out.
Engine detonates (pings) under heavy load, especially when hot,
potentially damaging pistons and valves.
Engine runs on after ignition is switched off (diesels).
Not enough advance causes the following problems:
Engine needs to crank over too long to start.
Idle too slow unless carb idle screw is turned quite a way in.
Lack of power.
Delayed acceleration when throttle opened under full load (engine bogs
down).
Engine runs too hot, potentially burning exhaust valves.
Poor fuel economy.
Perfect balance between what can be achieved with carb mixture and timing is
a back and forth thing. Best to static time the distributor timing, then
dial in the carbs, then go back to the timing. Fill up with the octane fuel
you plan to use on a regular basis. On a hot day, try accelerating at full
throttle up a steep hill from 30 mph in top gear. If the engine doesn't
ping, advance the timing a little bit, and try again. Continue this drill
until the engine pings, then back off just enough until the pinging goes
away. If any of the symptoms listed above under "too far advanced" occurs,
back the timing off a little more, until the symptom goes away. YMMV, no
warrantees expressed or implied, for entertainment purposes only, yada,
yada, yada.
David Riker
74 Midget
78 Midget
63 Falcon
http://personalweb.sunset.net/~davidr
----- Original Message -----
From Charles D. Sorkin <cdsorkin at ix.netcom.com>
To: Spridget List <spridgets@autox.team.net>
Sent: Tuesday, February 01, 2000 6:26 AM
Subject: Timing without a timing light (LBC content a-plenty)
> Dear list:
>
> Since odds are nobody is getting any in their Spridget in this weather (in
> the Northeast) my thoughts naturally turned to subjects more mechanical.
>
> Since I replaced the ignition system in the '74 Midget last month, setting
> the timing has been perplexing for me. I started out with the static
timing
> method described in the book, but that was just a coarse approximation.
> When I turn the distributor to the direction in which the engine idles
> fastest, and sounds most healthy, is the timing correct, or should it be a
> couple of degrees retarded? It didn't sound quite right at higher RPMs.
>
> Another engineering question: when I adjust the timing to 'x' degress
> advanced or retarded, am I actually changing the timing by 2x, to account
> for the fact that the crank makes two turns per revolution (one for intake
> valve, on for exhaust)?
>
> Regards,
>
> Charles
> '74 Midget
> '68 Sprite
> cdsorkin@ix.netcom.com
> Bloomfield, NJ
>
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