Some thoughts on why the engine stumbles when you put your Uni-Syn over
one carb, but not the other. Lets try to look at things from a couple of
different viewpoints:
-It's possible that the carb you are blocking is doing most of the work, and
when you block it, you are running off a poorly adjusted carb.
-One side may rusult in a bigger change in air-flow than the other.
-Leaky throttle shaft.
-Throttle opening on other carb too small.
-This is a Z-S. -could a perforated diaphram on one carb
or the other cause this symptom?
-Is there a blocked internal air (or fuel) passage?
-Fuel mix on other carb off.
-Where are the vacumn lines connected? The advance may be changing.
-Why should blocking the float vent affect short-term operation?
-Sticking float valve, causing some vacumn, instead of drawing in
more fuel.
-Wrong fuel (float) level? This is actually a good candidate, as
many people don't bother to "sync" their float levels. (In an SU
anyhow, you can remove the piston/needle, look down and *see* the
*assembled* float level in the bottom of the jet. I should add
this to my "Tuning SU Carbs" tech note.) When you block the air
intake, you are likely to cause a richer mixture, especially if the
fuel level is high, or the needle is off.
________
/___ _ \ Roger Garnett (garnett@tcgould.TN.CORNELL.EDU)
/| || \ \ Agricultural Economics | The All New:
| |___|| _ | 3 Warren Hall | South Lansing Centre For
| | \ | | | Cornell University | Wayward Sports Cars
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