I did my 1993 3.8, that was four steps up to 59. New bolts must always be used due to stretching. Here it is out of my Ford book:
Always use new cylinder head bolts to ensure a leak-tight assembly. Torque retention with used bolts can vary, which may result in coolant or compression leakage at the cylinder head mating surface area.
4. Install cylinder head bolts (eight each side).
5. Tighten cylinder head retaining bolts in sequence as follows:
a. 50 N-m (37 lb-ft)
b. 60 N-m (45 lb-ft)
c. 70 N-m (52 lb-ft)
d. 80 N-m (59 lb-ft)
Do not loosen all of the bolts at the same time, only work on one bolt at a time.
In sequence, retighten bolts one at a time in the following manner:
e. Long bolts: Loosen bolt and back out two or three revolutions. Retighten long bolt to 15-25 N-m (11-18 lb-ft). Then tighten bolt an additional 85-95 degrees and go to the next bolt in sequence.
F. Short bolts: Loosen bolt and back out two or three revolutions. Retighten to 10-20 N-m (7-15 lb-ft), then rotate an additional 85-95 degrees. Go to next bolt in sequence.
When cylinder head retaining bolts have been tightened using the above procedure, it is not necessary to retighten bolts after extended engine operation. However, bolts can be checked for tightness if desired.
Friday, April 13th, 2007 AT 7:37 AM