Quote:
Do you clip that one on the top of the rocker, it does not seem to have enough hook to grab the shaft 
it hooks under the rocker arm by the push rod and rests on top the rocker over the spring. They recommend setting up your springs on a bench style pressure checker and then use the supplied shims to calibrate so that the readings are the same and you are good to go. Mine was calibrated right from the box. It comes in very handy at the track and can also be used to check for any binding.
1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.42@138.27
Livin and lovin life one day at a time
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