454?
 

Looked at a 4 bolt main block out of a boat, supposedly a 454. Eng cast number is 1401544, kinda iffy on the first number as its rusty from all the salt water. Number on a front pad reads T10045XFF. Does say Hi Perf Pass on the block but my guess is that it is a mid 70's truck block??? It does have the extra external oil cooler hole by the filter. Appreciate any help decoding this if I have enough to go on here.

Re: 454?
 

the 1401 part of the number is most likely correct, but you're missing a digit in the last 4. The GM numbers with the 1401 prefix are 8-digit numbers.

Re: 454?
 

One book I have says: 14015445 454 75-87 TRUCK LIGHT-DUTY

Re: 454?
 

Makes sense, lot of 454 truck blocks in boats around here, didn't figure it was anything significant, but I didn't have anything close to the number. Next time I'm over there I will take a brush to it, quite a bit of rust to deal with.
Thanks Anders