1969 427 "512" Block Question

[Stefano]

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?

[BARRY]

HI MID DEC 1968

[SuperNovaSS]

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


Jason

[SuperNovaSS]

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

[Carleen]

<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

[69 Post Sedan]

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

Kurt

http://i300.photobucket.com/albums/nn2/brkyard/Parts/COPO-27.jpg

[the427king]

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

[Stefano]

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

[Carleen]

My Block is from mold GM4.

http://i517.photobucket.com/albums/u331/Nikkewi/SANY0007.jpg

[Fast67VelleN2O]

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

[bergy]

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.

[Steve Shauger]

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.

[Stefano]

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?

[Carleen]

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/u331/Nikkewi/sany0188_1295138117.jpg

[SuperNovaSS]

B 5 9 on the side:

http://i179.photobucket.com/albums/w301/super-novass/MarineL-88/CastingDateSmall.jpg

[black69]

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.

[Unreal]

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;

[Dicky]

<<GRAEMLIN_URL>>/haha.gif <<GRAEMLIN_URL>>/haha.gif <<GRAEMLIN_URL>>/haha.gif

[bergy]

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!

[6pakdave]

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/af228/6pakdave/70%20chevelle%20LS5/sschevelle074.jpg