* Head bolt pattern: While the overall bolt pattern might *seem* similar, the precise location and potentially even the number of head bolts may differ between the 1992 and 1997 heads. Forcing mismatched heads onto the block can lead to warped heads, cracked blocks, or head gasket failures.
* Intake manifold: The intake manifold bolt pattern is likely different, making it impossible to use the correct intake manifold.
* Valve train: The valve train components (pushrods, rocker arms, etc.) might have different specifications. Using mismatched parts will affect valve timing and could lead to engine damage.
* Internal differences in the block itself: While less likely to be directly incompatible, there's a chance of minor differences in the block deck height or other internal dimensions that could create issues.
In short, while both are SBCs, the year difference is significant enough to render the combination problematic at best and disastrous at worst. You need cylinder heads designed for the 1997 350 short block to ensure proper fit and function. Using the wrong heads risks expensive engine damage.
