Vacuum gauge kit
Vacuum gauges are helpful in diagnosing a host of problems including sticky valves, leaky head gaskets, poor compression, and (very importantly) they give a good indication of elevated exhaust backpressure. Google “Vacuum gauge interpretation” for a host of other diagnostic techniques using a vacuum gauge.
These kits include a small “T” fitting which allows sharing the normal attaching point for the top of the scavenge tube to the intake manifold on late model engines. On engines with early model manifolds, the small round “donut-shaped” boss area in the intake manifold just aft of the carburetor mounting flange will need to be drilled and tapped for 1/8″ pipe threads. In our dynamometer tests, the scavenge tube makes only a minuscule difference in the vacuum indications when connected (or disconnected). Eight feet of tubing is provided for cockpit mounting. In cases where cockpit mounting is not practicable, the vacuum gauge can be mounted in the engine compartment by using the remote mounting bracket (product number GAUG_08.3_354).
NOTE: Except for warranty exchange, this gauge is not returnable.