I just bought an 1986 Z28 parts car. According to the VIN, it should have the LG4 engine. I was looking at the engine today when i was pulling the Eldebrock intake off of it. And i noticed that the valve covers were corner bolted down. And the valve covers on my 87 LG4 are center bolt. Are these engines different between the two years? Or has one or the other been swapped out for something else? I didnt have time to write down casting numbers.

 

I forget. I think my 87 was corner bolt. However, the engine was replaced earlier in the cars life.

 

You have two "transition" years for LG4's.

'87 got center bolt valve covers and roller cam.

'86 got one-piece rear main seal.

'85 got higher compression, knock sensor, electric rad fan (at least that's what I've heard - may not be across-the-board).

Every later year kept everything the previous year had.