Engine casting number

[blown motor]

My 340 has the following numbers cast in the block. 2780930-340-2 Does the 2 mean that it was cast in '72?

[LEMOOREACE]

Its first digit in the "serial number" you want, not the casting number.  Cody taught me that.

http://www.cuda-challenger.com/cc/index.php?topic=95034.msg943122#msg943122

[blown motor]

Thanks. Looks like I'm going back under the car. 

[RzeroB]

My 340 has the following numbers cast in the block. 2780930-340-2 Does the 2 mean that it was cast in '72?

The date the block was cast can be found on cast into the opposite side of the block from the 2780930-340-2. Depending on when it was cast in '72 it could have went into a '72 or '73 model year car. Like Lemooreace said, the first digit in the stamped partial VIN on the passenger side oil pan rail will tell you what year car it was installed in and at what plant it went into the car. The "-2" suffix after the 2780930-340 is the casting mold revision number for that particular mold. When adjustments to the mold were made they would change the suffix number to reflect it. I have seen suffix numbers up to "-8" but I think that they could have gone as high as "-10" before the foundry would scrap the mold. Supposedly the lower the suffix number the better the block - but this could be another "urban legend".

[blown motor]

Well I'm out from under the car and the date is 5-31-72. The vin is 3010_713. So it went into a 73 car. What is the 0 or o? 10_713 will be the sequential number of the car, correct? The number where I put the _ is either a 6 or an 8. The bottom circle is there but the top of the number is missing so I'm not sure which it is.

[RzeroB]

The eight character partial VIN on the oil pan rail should start with a number indicating the production year, then a letter for the final assembly plant, then the six digit sequence number unique to the car the engine was installed in. So what looks like a "0" should be a letter and may be either a "C" for the Jefferson plant or a "G" for the St Louis plant??

[blown motor]

I'll look again tomorrow for to try and verify the second digit. The engine is not original to my Challenger and I don't think it was originally in a Chally or Cuda so it wasn't out of the Hamtramck plant. What cars were built at Jefferson and St. Louis? Stay tuned.

[Chryco Psycho]

The -2 on the end is the second time the mold was used
The year the block was cast is under the casting #2780930 on one side