need help with 1969 427 decoding..

[Bill Pritchard]

Sounds cool! Photos and/or more details would be welcome

[TimG]

I believe the casting states "hi perf" and "pass". This means 427 in two or four bolt configuration and not a truck engine. The two and four bolt were cast the same way and configured differently with two and four bolt mains and a larger oil plug for oil cooling on the four bolt blocks.

[69hurstSC]

so the "hi perf" has no relation to the hp of this 427 (335,390,425hp)? also, is there specific reasoning for stamping "pass" (assuming this means passanger) vs "conv" (again, assuming this stands for convertible) on the block?
we have all the casting #'s written down and i'll get them on here for you guys soon!

[TimG]

Correct, all the blocks were "born" the same way and machined differently.

[JHS]

Another difference between the 390 and 425hp is that the latter has a solid lifter configuration. Does the car still have the emmissions sticker on the rad support? It will denote the hp rating of the engine, I believe.