Reading a Vacuum guage

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Anonymous

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Quite a few questions from me tonight!

I going over my engine again tonight, little tuning here and there, and I hooked up my vacuum guage to the intake and noticed that the needle was vibrating VERY rapidly.

I checked my maunal and never saw a description for what I saw.

I know that I have low vac on my engine - always have, about 14hg at idle. It's been steady, so I know there are no leaks.

This time the needle was at 14hg, but flickering like a madman. No up-down sweeping, just really fast flutter.

Anyone have an idea what might be causing this?
 
HELLO CC

.....YOUR GAGE IS FEELING EVERY PULSE OF THE MOTOR. THIS IS DAMPENED OUT BY A RESTRICTION FITTING AT THE END OF THE VACUUM HOSE. THE HOLE IN THE FITTING SHOULD BE ABOUT .005 TO .01 OF AN INCH. THIS WILL SMOOTH OUT THE NORMAL PULSES AND ONLY SHOW THE LOSSES OF VACUUM. YOU ARE READING RAW VACUUM AND THAT MAKE THE READINGS UNREADABLE. CHECK TO SEE IF YOU HAVE THIS FITTING IN-LINE WITH THE GAGE. IF NOT THEN THE VACUUM IS TOO STRONG FOR THE GAGE.

.....ALSO AS I REMEMBER YOU HAVE A HOTTER CAM. THIS WOULD ALSO MAKE THE READINGS HARDER TO READ, AT LOW RPM'S.

.....IF YOUR MOTOR IS STUMBLING AT LOW RPM'S THEM RAISE THE IDLE TO SMOOTH THE MOTOR. THE HIGHER SPEED OF THE MOTOR WILL GIVE YOU MORE PULSES PER MIN. AND LESS TIME FOR THE PULSES TO RISE AND FALL.

.....IF YOU DON'T HAVE THE DAMPENER IN-LINE THEN,.... WHAT YOU SAW WAS A NORMAL READING. WHICH ISN'T EASY TO INTERPRET.

LIVE IN GRACE

LEROY POLL
 
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