Originally Posted by F-BIRD'88
Holley sec metering plates can be modified to accept holley main jets.
the 134-9 plate is way too lean. Drill Hole A to .081" at least.
or get a #21 and #27 plate. ( #21 plates are found in 3310 holleys)
Or drill and tap for holley screw in main jets and block Holes A
start rich.... work towards lean
Start at 80 pri and 78 sec with power valve plugs installed.
An educated guess suggests you will end up with best power jetting
right around 74 to 76 jets square ( with no power valve)
That means the Hole A in the metering plate will want to be +/- .080"
Start tuning rich big jets and work leaner noting power and spark plug appearance.
Do not go to the dyno test with just 4 jets. and no power valve plugs or carb bowl/metering block gaskets.
Bring extra spark plugs.
cheers - the dyno shop stock loads of accesories for holleys , so they have everything i need , thats great help on my sec plate as i did want to jet it . will have a look at the weekend .
also just to confirm i cannot use a distributer , i dont have the room so i cant stick one in,
i also have a ranges of jets from 70 to 80 ,they have all pv sizes ,
will get another set of plugs aswell .