Absolutely correct. In fact, you just described my Old 65 Alpine before it
melted a Piston. That poor tired engine had such little draw through the carbs,
that it was dam difficult to start when it was cold. And we are talking SERIOUS
blow by, which was it self, the cause of the picton melt down.
Note however, that if this engine is suspected of being tired with exsesive
blow by, it's also going to be smoking like John Force's funny car tires!.
There was a consistant blue clowd that follwed my Alpine, even with 2 cans of
STP and 50w oil !
To me...It sounds like this engine is fine, and all of the rough running can
be attributed to the gutted PCV valve (or just a tube in it's place), and the
attemps to tune it with that problem in place.
Replace the Valve, complete search for any other DPO or natural vacuum
leaks, and then a complete tune up, (to correct all previous attemps to do so),
and it should run perfectly. At least that's my remote view. It may still have
a cam, but the owner said it ran smooth when the vacumm gauge was in, which
leads me to believe that everything will be OK. Of course it's just my Opinion,
and I have seen/heard the car. I could be wrong. Hopefully the owner will
report back on his findings !!
Rich
>Rich,
>
>Not being one to pass up the opportunity for a little technical discussion,
>I have given your point of disagreement a little thought. If I understand
>you correctly, you agree that things like timing may affect vacuum, but
>indirectly and only for the reason that you don't have to open up the
>carburetor butterflies as much to get the same rpm, consequently, better
>vacuum.
>But what about blow-by? Certainly if it is significant, it would limit the
>amount of vacuum the pistons can create on the intake stroke. Take an
>extreme case, certainly you would have to agree that if there were no
>rings, then no matter what the cam profile was, the motor wouldn't generate
>any significant vacuum.
>
>Just some food for thought.
>
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