Help -- L98 aluminum head plug torque - 1989-1990 ??

Mar 04, 2007 2 Replies

Factory shop manual (1989) discusses aluminum head considerations (anti-seize etc.) and says 22 Ft-lbs.



Happened to look in Haynes for C4s. It says 22 Ft-lbs for cast iron heads and 12 Ft-lbs. for aluminum heads. Does not distinguish between L98s and LT-1s.



Misprint in the 1989 Factory Manual ??? Wonder what the



1990 manual says?

The old plugs came out very-very easily. Measured the cold torque on two of the old plugs -- 15 on one, 19 on another.



Ideas? Anyone have a 1990 manual?


No longer have my '92 manual but the LS1 says 15 Ft-lbs. for a new head and 11 Ft-lbs. for subsequent installations. Cadillac Northstar says 11 Ft-lbs. guessing not many install new heads on their Caddy.

Thanks Dad, I'll go with 12 and consider the 22 in the book as an accidental carry-over from the '88 manual (cast iron figure). Thanks too for the LS-1 figure -- couple of years away for plugs on that one.

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