Thread: trying to decipher block markings....little help??

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I have just been given a BBC for my '68 camaro project. I am told it is a 69 427, and the casting numbers are correct, now I am just trying to narrow down exactly what I have. I have looked all over the internet and tried to decode the markings, but I can not find any site that has anything except the casting numbers.
If anyone could give me a little help, I would much appreciate it.

I am trying to figure out exactly what the motor came out of , and what hp rating it origianally was....the casting number is 3963512, then there is a couple of markings on the front of the motor, I know one is a serial number (19c035500) the other is t0325LE and on the back of the block it is marked HI PERF PASS.

That block was used from 69-76. The best thing to try is look in Chevelle codes for 69 and see if there is a code TO listed. Then try the other body styles a big block was offered in. Otherwise its anybodys guess. As different years use different codes per vehicle.

thanks I will try that

What all i founf out is the motor is 427/450 69 to 71 hp 335-450 2 & 4 bolt mains (3963512)

thanx,
Your hp ratings for the motor have helped, that was really the main thing I was looking for.
I am still curious to see what it came out of, as I have started tracking down the TO blocks and have come up with zero as of yet.
You guys have been great with all of your help.

I just found out from another source that the LE for a V-8 is a 69 427 four bbl with a th350/th400. I am just curious as to how you arrived at the 335 hp. From my research the fact that it is marked as a hi perf pass should yield between 425 and 435 in stock trim. Is this not true?
Also, thanx for some help in narrowing down what the motor came out of, nobody so far has been able to narrow it down at all. everyone tells me it could have come out of any car that was available with the big block.
Now, could somebody tell me if the 427 LE was used in the COPO Camaros? I do not think this would be the case since they were supposed to be backed by auto trannys and I know all the COPO camaros were backed by 4 spds.
Just food for conversation.
Thanx
Craig

Pull out a spark plug and try to match it up with the correct year . Sometimes you can get lucky, when the different years change the plug code no. Taking into account the previous owner had the right plugs.