I recently purchased an E Block 400 and have some questions about some casting numbers.
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Clearly shows 390925 E, please ignore the red.

It has a.i.r California C heads, which i have never seen in the wild until i got this. However, the stamp on the passenger head indicates what i assume to be service replacements?

SR = service replacement? Instead of the Vxxxxxx.




It also has the Forged steel crank "L" mark on the crankshaft to flywheel flange


But what really has me stumped is the casting number on the distributor pad. I expected to see 66 or 67 but behold....


I am open to any and all interpretations but i am thinking a service replacement block with heads built in 69? Is that even possible? Please let me know your thoughts. Thanks in advance.

 

Class racing. It will be interesting to see what is inside of that thing, but I suspect that's a class legal engine a couple years into it to whup the G block's butt. That might be a mean engine.

 

First of all, every single crank Olds put into 1964-67 model year engines was forged. Second, 69 is the day of the year and has noting to do with the actual year. The 5 above it is the mold number.

 

Thanks Joe. That solves the distributor pad question. Is there a way to tell the difference between a 66 and a 67 block? Also, am i right in guessing service replacement on the C heads per stamp? Any way to tell year of the heads? Thanks!

 

My 67 block also has a 5... not sure that's conclusive.

My 64 dated B block 400's are "1"
My 65 dated B block 400's are "2"

 

Again, my point that the large number isn't the year of casting. Also, pay attention to the calendar day - I've seen blocks where the large number might have correlated to the correct calendar year for the car, but the actual casting date was so late in the year that it would have been cast after the model year changeover. And if one really subscribes to the large number as casting year myth, a "5" on an E-block would be 1970, so clearly that can't be true. As another example, I've seen a block from a Rallye 350 with a "3" mold number (which the myth claims is 1969) but the casting day is 33, which is Feb 2, 1969. Clearly not realistic for a car built in the 1970 model year. I've seen a D-block with 4 and 5 mold numbers, E-blocks with 4, 5, and 6, a 455 with a 1969 VIN derivative and a 4, etc, etc.

 

I don't think the large # is year...just the casting/mold # after modifications.

But with that said, my B block 64/65 casting #'s DO seem to correlate to the end of the 64 year.
(Mid-December specifically with that #2 December 18th(352) block.

My 1's are mostly 300's, my 2's 0-100's.

I find this stuff kinda interesting.

 

Peter, here's a B-block to add to your collection of photos. I'll just leave this here.

 

Dayum!
I actually HAVE that picture in my grid above(2 next to each other actually!) never noticed...
(or I did and that's why I circled it in pink!)

So do you think that's a early production Feb, 64 block?
Or did they drag the #1 mold out in feb '65? (or just continued using it indefinitely?)

 

Well, either it's an insanely rare pre-production block, or it was cast in Feb 1965 using a #1 mold. Guess which one I think is true.

 

I have owned E blocks with 3, 4, 5 and 6. Date codes 4, 34, 87, 114, 152, 158, 199, 242.

 

I know which one you’re thinking, Joe..
How early do you believe they would start casting production blocks for a new engine debuting October/November?

That that’s good information RUND… 4 molds for 2 years of blocks.
I wonder what 68-69 and 70——through whenever had?

 

Peter, your sheet shows not one but two blocks with 1 and 51. Your calendar calls them 1965s.