1969 427 "512" Block Question
 

1969 427 "512" Block Question?

Does anyone know a definative time period as to when the casting dates went from the side of the 427s to the rear of the block on top by the belhousing?

Re: 1969 427 "512" Block Question
 

HI MID DEC 1968

Re: 1969 427 "512" Block Question
 

I think it was mid 69. I have a B 5 9 block here with the casting date on the side.


Jason

Re: 1969 427 "512" Block Question
 

I just looked in, "Chevrolet by the Numbers" by Alan Colvin. He says the change was made Nov 17th, 1969. The date location was changed at the same time the distributor boss was changed from the high to the short tower design.


Jason

Re: 1969 427 "512" Block Question
 

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SuperNovaSS</div><div class="ubbcode-body">I just looked in, &quot;Chevrolet by the Numbers&quot; by Alan Colvin. He says the change was made Nov 17th, 1969. The date location was changed at the same time the distributor boss was changed from the high to the short tower design.


Jason </div></div>

Its not true.

http://i517.photobucket.com/albums/u331/Nikkewi/003.jpg

Re: 1969 427 "512" Block Question
 

My MN block was cast January 27th and it's cast on the side of the block.

Kurt

http://i300.photobucket.com/albums/n...ts/COPO-27.jpg

Re: 1969 427 "512" Block Question
 

It is a great reference book, but has a few errors in it.

Re: 1969 427 "512" Block Question
 

I wouldn't think the same plant would go back and fourth with where they placed the casting dates?

Re: 1969 427 "512" Block Question
 

My Block is from mold GM4.

http://i517.photobucket.com/albums/u...i/SANY0007.jpg

Re: 1969 427 "512" Block Question
 

I have a May of 1969 block and its stamped on the back of the block.

Re: 1969 427 "512" Block Question
 

If my memory is correct, the location of the date tags were changed in late February thru March of 1969. They were changed simply because date tag charactors wouldn't draw properly from that angled surface. Thus, the date charactors on the early castings were often hard to read. Also, the cope (top) mold machine operator had to index his pattern out of the machine once per hour to change the time clock - so he could better clean/monitor the date tag condition. It was a running change on the patterns. The muller on the MIV block line was the oldest and least efficient ( I believe that it was made by Baker Perkins) of the 8 sand mullers (the rest were all Simpson mullers). Thus casting finish on the BB blocks was never great.

Re: 1969 427 "512" Block Question
 

I don't have a definitive date but late Feb is when I believe the casting date switched from the side to the top. I think the earliest pic I have with date on top is C 5 9.

Re: 1969 427 "512" Block Question
 

Thanks for the info, guys.


Since there were more 427 Corvettes than Camaros, does the NCRS keep any of this data?

Does anyone have a January or earlier cast block with the date on the top?

Re: 1969 427 "512" Block Question
 

I was looking at the block at ebay and the earliest block that has Casting in the rear that I found was a C 5 9 Casting.

http://i517.photobucket.com/albums/u...1295138117.jpg

Re: 1969 427 "512" Block Question
 

B 5 9 on the side:

http://i179.photobucket.com/albums/w...gDateSmall.jpg

Re: 1969 427 "512" Block Question
 

I have seen more than a few 396 L78 blocks with A 69 codes on top side (old shortblocks, never rebuilt). I know where the engines are, but never took pictures. The dates were later in january (I think one was 22-24 ish)
I see no reason why a 512 block would be any different.

Re: 1969 427 "512" Block Question
 

Bergy, you must be an old foundryman!

Reminds me of the story of an old foundryman who, every morning, would unlock his top drawer, look at a piece of paper, and then return it to the drawer and re-lock it. His colleagues would ask him what was on the paper, but he refused to tell. This went on for years and years. Well, unfortunately, he died one weekend, and a few weeks later when his replacement moved into the his old office, the new guy pried open the drawer, and found the note, which read, &quot;Cope is the top, Drag is the bottom.&quot;

Re: 1969 427 "512" Block Question
 

[img]<<GRAEMLIN_URL>>/haha.gif[/img] [img]<<GRAEMLIN_URL>>/haha.gif[/img] [img]<<GRAEMLIN_URL>>/haha.gif[/img]

Re: 1969 427 "512" Block Question
 

Good one Gary! Notice how difficult it is to read the date on the picture that Jason posted above? That's why the date tag was moved to the TOP pattern!

Re: 1969 427 "512" Block Question
 

This was in a 70 SS Chevelle I bought. Was claimed to be a LS5 warrenty engine, I think it was an early 1970 date code , if I recall the car was a late 69 build.

cheers Dave

http://i1010.photobucket.com/albums/...hevelle074.jpg