Engine date vs engine component dates?

[Jeff H]

Some recent posts have me wondering what engine components should be dated for the time frame before the engine was assembled vs what components could be after engine assembly but before the car's assembly. When an engine was assembled, what was actually installed on the motor as it was initially assembled? Heads & intake?

So would the following components need to be dated before the engine assembly date?
- distributor
- alternator
- fan
- exhaust manifolds
- carb
- spark plug wires
- pulleys

Is there a known assembly sequence that allows for dating certain components? I'll use my 1970 L78 as an example. My car is 01C of 1970 and the motor is T1030CKO of 69. So should the components on the engine all be dated before 10/30 or can I use components from Nov, Dec and Jan as long as they are prior to the car's build date? I've always thought everything should be dated prior to the engine's assembly date but if a motor sat in a corner for a while, would it be a fully dressed motor?

[68SSCamaro]

Al Colvin's "Chevrolet By The Numbers" covers this subject. Use that and the Assembly Manual to determine what components are part of the Engine Assembly and what is added at the Car Assembly plant.

The engine assembly includes the long block including distributor and flywheel. So block, heads, intake, exhaust manifolds and water pump. Also thermostat housing, engine lift brackets and for pre-69 the smog bracket on the intake.

Car assembly include alternator, starter, carburetor, smog pump, power steering pump, coil, air conditioning, pulleys, fan and all the brackets that go with these.

There are a bunch of little things that go on the engine at various points that maybe someone else can help with. These would include spark plug wire stands, distributor vacuum line stand, power brake vacuum fitting on intake, etc. This would make a good project for someone to put together.

[70-SS/RS-L78]

Jeff there is a VERY INFORMATIVE thread at Nasty Z28 which I asked the same question. A GM Engineer from the motor shop answered many of assembly and engine painting procedures that have puzzeled me over the years...

[Mr70]

Sounds like JohnZ.
He frequents here too.

[JohnZ]

The easiest way to determine what came on the engine from the engine plant and what was installed at the car assembly plant is to look in the assembly manual; anything that has a part number callout was installed at the car assembly plant, and anything that doesn't came as part of the engine assembly as shipped from the engine plant.

Chevrolet engines were pretty bare-naked leaving the engine plant, as posted above; automatic engines just had a flexplate, and manuals had the flywheel, clutch, bellhousing, and clutch fork. Other than the distributor, that was about it, except for the orange-painted parts.

Here's a photo from the shipping dock at Flint Engine, taken in 1955; engine state of dress at that point didn't change until the early 80's.