604 New Engine Check List — (Basic Prep)

Questions or Problems contact us at: Ph.: 330-540-7223 or email brad@race-1.com

(all information below is a recommendation from Race-1 not necessarily from GM)


Inspect Cylinders for debris (bore scope)

Inspect intake manifold for straight and square

Inspect and insure lifter bars are in place

Inspect fuel pump pushrod bore for debris and burrs


Remove rocker arms and lubricate roller


Check torque on rocker studs — 55 to 58 ft. lbs.

Check torque on head bolts — 65 ft. lbs. (No specific order is necessary)

**special note** the 2 short bolts adjacent to the factory seal bolt should be checked at a reduced torque 63 to 64 ft. lbs. recommended


****CHECK Posi lock threads for low percentage of thread*****

Reinstall rocker arms adjusting valves and locking the posilocks in the appropriate manner.


Check rear galley plugs above camshaft (¼” square)

Check head plugs on the side of the heads in between ex. Ports (5/16 square)

Degree balancer and mark desired timing lines

Install oil pressure fitting

Add silicone sealer to the top of the soft plug that blocks the factory dipstick hole


Grind the Right Front (middle) (long) timing cover bolt (604)

This is the long bolt on the fuel pump side and it will interfere with many water pump set ups—REMOVE the bolt and grind 3/4 of the head reinstall** (check clearance to water pump)


Check oil pan bolts for tightness

Check rear seal housing fasteners for tightness

Check oil drain plug for tightness

Check oil filter adapter bolts for tightness

Turn the Breathersshield should be towards the front of the engine.


PRO SERIES PREP >>>> the valve springs can be removed for testing and installed height can be checked and adjusted with shims. (1.780 Min for 604) **check specific rules on shims**

**During this procedure you can insure that no debris was left around the valve guide area**

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