|02-29-2012 10:15 PM|
|02-29-2012 09:14 PM|
|DoubleVision||Guess What? This thread is 4 years old.|
|02-29-2012 09:00 PM|
I remember years ago when I worked in a Salvage Yard that the old man at the counter sold 350 4 bolt engines per the 7th bellhousing bolt hole at the top, and the casting number 3970010 meant that it was for sure a 4 bolt, guess what,, I proved him wrong one day on a bet. It can be either 2 or 4 bolt. Even the # 3970010 on the back of the block, does not mean it is 4 bolt. That number was used on both 2 and 4 bolts. This number was to mean it had 10% nickle, As for as the .010 on the side or under the timing cove or where ever it might be, came along at a later date, say "80's, I have always been told it meant a 10% nickel content, hence the cylinders held up better for ware. The only way I would believe it for sure is to see it written down in a GM specs book somewhere... Dad
|04-04-2008 09:30 AM|
|XNTRCI-T||I'm pretty sure the 010 and 020 were on the back of my block, but I wouldn't bet a paycheck on it.|
|04-03-2008 04:10 PM|
You are correct as far as any numbers on the sides.
|04-03-2008 03:40 PM|
|DoubleVision||The marks on the rear or under the timing chain cover 010 and 020 represent the percentage of tin and nickel in the casting as mentioned, but on the side it means elsewise.|
|04-02-2008 07:12 PM|
|04-02-2008 06:21 PM|
|DoubleVision||Is the casting number 3970010? notice it ends in 010? this is common on these casting number blocks cause its part of the casting number. The past rumour of that 010 marking on the side indicates a 4 inch bore, but this has never been confirmed either as the true meaning, so it reflects back to what I just said, it means 3970010.|
|04-02-2008 04:08 PM|
|XNTRCI-T||My block has both 010 and 020 on it. It is a '79 350 out of a truck, 4-bolt. I have heard the 1% nickel - 2% tin explanation many times, including from the racing engine shop that built my short block. I don't know for sure if it's true, but it does help me sleep better at night!|
|04-02-2008 03:47 PM|
When high performance and heavy duty applications (early to mid 60s) caused blocks to fail, they started adding nickel to strengthen the blocks. By 1970 almost all blocks were cast with 1% nickel content, thus all of the blocks had 010 in the castings.
As for 020, my understanding is 2% nickel was used (I hadn't heard of using tin). I've never seen a block with 020 casting.
I can't recall where I read about this, and as always even if it's in writing, don't make it so.
|04-01-2008 04:07 PM|
I think the whole nickel tin thing is a big myth also. It supposedly means 010 is 1% nickel and 020 is 2% tin. Correct me if i'm wrong but If it was 10% nickel and 20% tin it would no longer be cast iron.
|04-01-2008 03:59 PM|
|Double_v23||That is just a myth, all blocks from that era had comparable amounts of nickel in them. Sometimed they put 010 on one side and 020 underneath it. So does it have 10 and 20 percent nickel? nope.|
|04-01-2008 03:23 PM|
|chevyman420||so it does mean something and it is stronger then because i think i got that from Mortec.com|
|04-01-2008 03:20 PM|
010 is 10% Nickel
Actually from some research I did on small blocks, the 010 cast into the side of the block signifies the percentage of nickel used in the iron for the casting. The 10% nickel content adds strength to the iron.
|04-01-2008 03:16 PM|
|chevyman420||OK cool but if i remember correctly i think i read somewhere that it means that there is more nickle or something and that it's stronger?|
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