Help with 340 decoding

[Troy]

I'm waaaaay out of my element on this one and, so far, the information I've found on the internet is far from conclusive. Seller claims it's from a 71 Challenger based on GG book.

Casting #: 2780930-340-8
There are at least two large '4' castings
Casting Date: 6-17-71
Arrow pointing at 3:00
Arrow pointing to 'D' (on 'D'/'N')
VIN Stamp hard to read but looks like "2A121**8"
Stamping on front pad: "HM 340R 720142"
Has a steel crank drilled for a 4-speed.
Intake casting number matches 1972 340 and it has a trashed Thermoquad.
Color is dark blue - never been painted that I can tell.

Looks like a very late 71 casting date for an early 72 Lynch Road car. I have no idea how to decode that last part on the front stamp. What was manufactured at that plant?

I'm definitely lost on the heads:
one has "3418915H" casting with 2590 date
other has no discernible part # but has "34 80 6"(?) with a large 'D' in the same spot and 2880 date
Both say "AAWJ"

Looks like it's never been apart. Pulled it out of a pickup so the pan and motor mounts are incorrect for a car. Any ideas on value?

Troy

[Challenger6pak]

71 340's were blue.  It might be a motor for a late 71 Road Runner. I am pretty sure if it was an Ebody motor the VIN start 1B. 

[Troy]

I got an answer elsewhere and it appears to be from a 72 Charger Rallye. Still not sure why the heads are so much earlier than the rest of the engine.

I had read that the engines after April 71 were blue and earlier were still orange.

Troy

[polarbear123]

Those are the right heads for 71, 72, 340.

[Challenger6pak]

The 72 should have a cast crank.

[Troy]

The 72 should have a cast crank.

Um, not always. This is why I said "the information I've found on the internet is far from conclusive". For example, Allpar actually contradicts itself saying steel cranks through 1973 in one spot but later lists "1972-1973: cast crank" then later states "crankshaft was switched from forged to cast somewhere in the production cycle, believed to be in early April 1972; a milder camshaft was used".

From what I've found and heard from guys with more knowledge than me in the last few days, Chrysler changed the color from orange to blue in late 71 and switched to cast cranks some time in 72. So, not all 71 engines were orange and not all 72 and later engines had cast cranks. On the crank issue, if they switched in April 1972 that would be 9 months into 1972 model year production so most would have had a steel crank. This is how I got all confused looking at the engine - none of the numbers and "supposed to have" pieces that I'd read about previously were there. This one for sure doesn't have a cast crank or balancer.

Troy

[72rtchallenger]

the restoration book i have says anything with a engine cast date  before july was in the same year car like 71 and anything after was 72,,not sure if that helps

[Moparal]

My 72 340 cuda had a steel crank and the 72 340 I just built for a MCG member was steel also.  72 440 chryslers were steel too.  I have found all 73 engines cast so far. Just from experience and no book reading

[Troy]

the restoration book i have says anything with a engine cast date  before july was in the same year car like 71 and anything after was 72,,not sure if that helps

Hard to say on that. Engine lead times ("assembly" dates) were anywhere from 2-6 weeks (sometimes a LOT more depending on application). Casting dates could have been 2-6 weeks (or more) prior to that. Production of cars for the next model year started about the middle of July and they needed a supply of engines on hand so, assuming 2 weeks from cast to assembly and 2 weeks from assembly to installation all July built cars would have June or earlier engines. Make that 4 weeks each and your July cars had May engines.

This engine is an example of one that proves your book wrong. It was cast on June 17 but not assembled until October 4. That's 109 days (15.5 weeks) from casting to assembly. The original car is long gone but it was probably built in late October or early November. The heads would have been 14-15 months old at that time.

There has to be at least some lead time because engines were built in different plants than the cars. I have a 440 in another car that was assembled 10 days prior to the car. That's about the closest I've seen. A friend of mine has a 440 that was assembled nearly 8 months prior to his car's build date. They didn't produce Hemis in 1967(or was it 68?) because they made too many in 1966. Most 1968 Hemi cars (at least early ones) had engines over a year old.

I have learned that it's hard to be definitive about anything when discussing Mopar.

Troy

[72rtchallenger]

Hard to say on that. Engine lead times ("assembly" dates) were anywhere from 2-6 weeks (sometimes a LOT more depending on application). Casting dates could have been 2-6 weeks (or more) prior to that. Production of cars for the next model year started about the middle of July and they needed a supply of engines on hand so, assuming 2 weeks from cast to assembly and 2 weeks from assembly to installation all July built cars would have June or earlier engines. Make that 4 weeks each and your July cars had May engines.

This engine is an example of one that proves your book wrong. It was cast on June 17 but not assembled until October 4. That's 109 days (15.5 weeks) from casting to assembly. The original car is long gone but it was probably built in late October or early November. The heads would have been 14-15 months old at that time.

There has to be at least some lead time because engines were built in different plants than the cars. I have a 440 in another car that was assembled 10 days prior to the car. That's about the closest I've seen. A friend of mine has a 440 that was assembled nearly 8 months prior to his car's build date. They didn't produce Hemis in 1967(or was it 68?) because they made too many in 1966. Most 1968 Hemi cars (at least early ones) had engines over a year old.

I have learned that it's hard to be definitive about anything when discussing Mopar.

Troy

yea i know the book is just a reference only and cant be seen as 100% correct,,was just throwing it out there,,I have seen many mopars that are not exact as what there suppose to be even if its numbers matching,,my own 72 challenger has some 71 left overs

[Troy]

Ok, slight modification...

it looks like I'm missing 2 numbers from the front pad. They would be the ones corresponding to the assembly date. Guessing at the most likely date gives "3672" or August 17 which makes it 2 months after the casting date. That looks more realistic than October (we had guessed "3720" before but that didn't leave enough for the sequence which are the last 4 digits).

If this thing were 2 years older it would almost exactly match my Challenger...

Troy

[Chryco Psycho]

72 were steel crank , 73 were cast