Whats the sequence i need to follow when tightening head bolts on a 1999 chevy tahoe 5.7 liter 4 wheel drive

The 2014 Chevy Spark intake manifold torque sequence and torque specs depend on the engine type. Here are the torque specs and sequence for each engine type:
1.0L Engine:

• Step 1: Tighten the bolts to 44 inch-pounds (5 Nm).
• Step 2: Tighten the bolts to 89 inch-pounds (10 Nm).
• Step 3: Tighten the bolts to 18 lb-ft (25 Nm).

Torque sequence: 8 4 1 5 9 7 3 2 6 10
1.2L Engine:

• Step 1: Tighten the bolts to 44 inch-pounds (5 Nm).
• Step 2: Tighten the bolts to 89 inch-pounds (10 Nm).
• Step 3: Tighten the bolts to 18 lb-ft (25 Nm).

Torque sequence: 8 4 1 5 9 7 3 2 6 10
It's important to follow the torque sequence and torque specs carefully to ensure that the intake manifold is properly secured and sealed. Over-tightening or under-tightening the bolts can cause leaks or damage to the engine.

There were two designs that year.
First design with M11 bolts:
1) Tighten to 22 Ft/lbs in sequence
2) turn 90 degrees in sequence
3) turn another 90 degrees in sequence
4) turn 50 degrees in sequence

Second design with M11 and M8 bolts
1) tighten all M11 to 22 ft/lbs in sequence
2) turn all M11 90 degrees in sequence
3) turn all M11 70 degrees in sequence
4) tighten M8 bolts to 22 ft/lbs in sequence

Install the cylinder heads. Use new gaskets and tighten the bolts, in sequence, as follows:

1. Step 1: Bolts 1-8 to 20 ft. lbs. (27 Nm)
2. Step 2: Bolts 1-10 verify torque without loosening
3. Step 3: Bolts 9-12 to 10 ft. lbs. (14 Nm)
4. Step 4: Bolts 1-8 plus 1 / 4 (90 degree) turn
5. Step 5: Bolts 9-12 to 19 ft. lbs. (26 Nm)

You must use new bolts, failure to do so will result in redoing the job.

Tightening sequences
intakes side 15 13 11 12 14
center 10 3 1 5 9
exhaust side 7 6 2 4 8

Step 1
all 11mm bolts 22 ft lbs
Step 2
all 11mm bolts turn add 90deg
Step 3
11mm bolts 1-8 turn add 90 deg
11mm bolts 9 and 10 turn add 50deg
Step 4
all 8mm bolts 22 ft lbs

sure. 2.5 liter engine, right? Thanks for using FixYa!

Secure the head in place with the mounting bolts. Coat each bolts with clean engine oil, and hand-tighten. Tighten the cylinder head bolts to the following specifications:

1. Step 1: all bolts to 22 ft. lbs. (29 Nm).
2. Step 2: all bolts to 51 ft. lbs. (69 Nm).
3. Step 3: loosen all bolts by 180 degrees, then loosen an additional 180 degrees.
4. Step 4: bolts 1 and 2 to 25 ft. lbs. (24 Nm).
5. Step 5: bolts 3, 4, 5 and 6 to 11 ft. lbs. (15 Nm).
6. Step 6: all bolts plus 80-90 degrees.
7. Step 7: All bolts plus 80-90 degrees.

Fig. 1: Cylinder head bolt tightening sequence-2.0L SOHC engine





Fig. 2: Cylinder head bolt tightening sequence-2.0L and 2.4L DOHC engines

Tighten the bolts in 4 steps as follows:
a. First: all bolts to 25 ft. lbs. (34 Nm).
b. Second: all bolts to 50 ft. lbs. (68 Nm).
c. Third: all bolts again to 50 ft. lbs. (68 Nm).
d. Fourth: all bolts an additional 1 / 4 turn.

Do not use a torque wrench for the fourth step.

Hope helps (remember to rate and comment this).

from autozone.com:

1. Tighten the cylinder head bolts in the sequence shown in three steps, as follows:
   1. Step 1-27-31 ft. lbs. (37-43 Nm).
   2. Step 2-tighten an additional 85-95 degrees.
   3. Step 3-tighten another 85-95 degrees.

Fig. Fig. 9 Tighten the cylinder head bolts in three steps using the sequence shown-4.6L and 5.4L engines

1.8 liter..NOTE: Lubricate the cylinder head bolts using the specified engine oil.

Install the cylinder head bolts. Tighten the cylinder head bolts in 2 or 3 steps in the sequence shown to 76-81 Nm (56-60 lb-ft).


1.9 liter
Apply a light coating of engine oil to the threads of the new cylinder head bolts. Install the new cylinder head bolts to the cylinder head. Following the sequence shown below, tighten the cylinder head bolts to 40-60 Nm (30-44 lb-ft). Loosen all cylinder head bolts approximately two turns, then retighten the cylinder head bolts to 60 Nm (44 lb-ft) following the sequence shown. After tightening, turn all bolts 90 degrees, in the same sequence. Complete bolt tightening by turning them an additional 90 degrees, in the same sequence.

Cylinder heat bolt torque:
Torque sequence --------- front | 7 3 1 5 | | 8 4 2 6 | --------- Step 1: Torque all bolts in sequence to 14 Ft/Lbs Step 2: Torque all bolts in sequence to 29 Ft/Lbs Step 3: Torque all bolts in sequence to 36 Ft/Lbs Step 4: in the sequence, loosen the cylinder head bolts three turns. Step 5: Tighten short bolt to 15 - 32 Ft/Lbs Step 6: Tighten long bolt to 30 - 36 Ft/Lbs Step 7: Tighten all bolt to 175- 185 degree note: Do not loosen all of the cylinder head bolts at one time. Each cylinder head bolt must be loosened and the final tightening prior on the next bolt in the sequence.
Main bearing torque:
Torque sequence: Step 1: torque bolts to 91 Ft/Lbs with the exception of the rear main bearing cap Step 2: torque rear main bearing cap bolts to 88 Ft/Lbs Step 3: torque brace bolts to 40 Ft/Lbs
Connecting rod torque:
Torque sequence Step 1: Torque to 29 Ft/Lbs Step 2: Turn an additional 90 degrees

1. For 1.8L engines, tighten the bolts in sequence, as follows:
   1. Step 1: Bolts 1-10 to 22 ft. lbs. (29 Nm).
   2. Step 2: Bolts 1-10 to 43 ft. lbs. (59 Nm).
   3. Step 3: Loosen bolts 1-10 completely.
   4. Step 4: Bolts 1-10 to 22 ft. lbs. (29 Nm).
   5. Step 5: Bolts 1-10 plus 50-55 degrees.
   6. Step 5: Bolts 11-14 to 74 inch lbs. (8 Nm).
      
      Fig. Cylinder head torque sequence-1.8L engine
      
      
      Fig. Tighten the valve cover bolts in sequence-1.6L and 1.8L engines