340 engine serial number decode

[Plumcrazy67gt]

Hi I have a 340 with a 727 in my 67 GT

I found the serial number and was wondering if anyone could decider it for me GM340P33640452

Thanks in advance

 

[crackedback]

Not the serial number That's above pan rail

G - 1971
M - Mound Road Plant
340
P - Premium Fuel
3364 - 10/13/1970 Build date
0452 - 452 unit that day.

 

[gunmetal72]

how does 3364 decode to 10/13/1970? just curious

 

[Plumcrazy67gt]

Awesome many thanks. It was the number on the drivers side at the front of the block just below the head

 

[Rocky_JS]

Chrysler used a 10,000 day calendar starting in July of 61.
http://maxwedge.com/articles/10k.php
Day 3364 is Tuesday, October 13, 1970 as stated. This is the date the engine was "assembled" at the engine factory stated. Then it was sent to the car plant and the vin stamp was added when assigned to a car. The pan rail VIN for a Hammy car with this engine would be 1BXXXXXX 1 being the model year 1971, B car plant is Hamntramck then X the last 6 of the cars vin.

how does 3364 decode to 10/13/1970? just curious

 

[DA4AD]

Just to clarify using the following #'s
340 Block
Casting # Right side 1-27-71.................. Date forged/cast (Jan 27, 1971).
Casting # left side 2780930-340-5........... Part #.
Pass Side # 1B365483............................Last eight digits of car serial #.
Front Left # GM 340P 35460007..............Date machined (April, 13 1971).

So for instance a 1973 car could have a 1972 block?
please correct me if I'm wrong as i am trying to find a correct date coded motor for my car.

 

[Rocky_JS]

as the model year started before the calendar year ended. So it could likely be cast the previous year. 3 to 6 months from what I have seen is typical from cast to assembly to assigned to a car. The above example is about 3 months.

Just to clarify using the following #'s
340 Block
Casting # Right side 1-27-71.................. Date forged/cast (Jan 27, 1971).

YES

Casting # left side 2780930-340-5........... Part #.

Casting number the -5 is a mold revision number from the original mold after x amount of revisions molds are replaced.

Pass Side # 1B365483............................Last eight digits of car serial #.

close. the 1 = 1971 model year of vehicle, B = car assembly factory in this case B = Hamtramck, last 6 of car VIN.

Front Left # GM 340P 35460007..............Date machined (April, 13 1971).
So for instance a 1973 car could have a 1972 block?

YES

please correct me if I'm wrong as i am trying to find a correct date coded motor for my car.

yes need to know the build date of the car. but a 73 model vin block will start with a 3 even if casting date is 72

 

[DA4AD]

Thanks, just using the #'s for reference.
My car was built Feb 15, 1973.

 

[Rocky_JS]

You likely would have a block cast +/- 3 months prior to car date

Thanks, just using the #'s for reference.
My car was built Feb 15, 1973.

 

[mbaird]

You likely would have a block cast +/- 3 months prior to car date

not necessarily , If I remember correctly your dart has a low vin.. the factory would use left over blocks I would imagine. I don't believe there were a lot of 340 cars built in 73... could be wrong..

 

[gunmetal72]

Chrysler used a 10,000 day calendar starting in July of 61.
http://maxwedge.com/articles/10k.php
Day 3364 is Tuesday, October 13, 1970 as stated. This is the date the engine was "assembled" at the engine factory stated. Then it was sent to the car plant and the vin stamp was added when assigned to a car. The pan rail VIN for a Hammy car with this engine would be 1BXXXXXX 1 being the model year 1971, B car plant is Hamntramck then X the last 6 of the cars vin.

Thanks, I did not know that, I learned someting new today,cool:cheers: