FB engine welch plug size

[Fraze]

The two welch plug cavities behind the side plate on my FB engine measure 1.208" - the nearest "real" size is 1.218" -     (1 7/32"). In my Holden master parts catalogue the size is listed as 1 1/4". Can any one throw some light on this discrepancy? Thanks Frazer

[weddo]

Frazer,
Only 1/32 difference. Put the welsh plugs in the freezer for a couple of day, your motor out in the sun for a few hours then tap then in

regards
Weddo

[Fraze]

The correct welch plug for the FB engine (behind the side plate) is 1 7/32", contrary to what is shown in my GMH parts book. Cheers Frazer