>It turned out to be....the PCV hose. That is...the largish hose going
>from the carb to the valve cover. I *think* this is the PCV
>hose...right? Popped it back on and the car runs just fine.
>What's bothering me about this is that I can't remember this
>connection being so critical to the decent running running of
>any other car I've owned. I realize that I created a vacuum leak
>here, but somehow I always thought of the PCV connection point
>and being a somewhat...uh..."harmless" air intake port.
>An I making any sense here? :-)
Remember, a Spitfire doesn't have pcv in the normal sense. There is no
fresh air supply into the engine. That hose only drains off excessive
crankcase fumes. It's more like a Briggs&Stratton then anything else in
that sense. Don't much like it myself, because of the fumes that stay
in the crankcase.
So when you popped off the line, you really did create quite a vacuum
leak. What had been a sealed end hose (sealed with the engine block
that is), was now open to the atmosphere, and wreaking havoc with your
fuel mixture. Much like when you pop a fairly substantial vacuum hose
of a more normally designed engine.