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I bought a rebuilt engine and have torn it apart to change the gaskets. It is an 1981 LT9 block, with mild edelbrock cam, and maybe 202 heads. When I purchased the motor I was told they were camel hump and misidentified them (they have a hump looking thing on them). I was wondering if anyone could help me identify them. I've tried to look up the casting number, but it's very very difficult to read and I haven't been able to find a match. I think the number are either 378468 or 376458. There's also a casting number GM12T
After comparing the casting identifiers to the casting numbers they look similar to 450s. I'll attach some pics. Any help would be appreciated. I'm not sure if I've gave anyone enough to go on.
Those are 305 heads and probably don't have 2.02 valves in them unless they were reworked. Highly unlikely though as the water jacket around the valves is pretty close to the valves in the stock configuration. Your casting mark is on the bottom right of the chart below with the corresponding casting numbers. Double hump heads are the casting mark shown in the upper left of the chart. I hope this helps.
Head Identification
