engine colour change

[aussie]

Does anyone know when the engine colour changed from hemi orange to blue on a 340, think it was around mid to late 71. If anybody can help that would be great. 

[73_Cuda_4_Me]

http://www.mymopar.com/enginecolors.htm

[JH27N0B]

I've seen the subject discussed a number of times on forums before, and my recollection is that it was around March of '71 that 340 engine production changed to a different plant, and that is when the color change from orange to corporate blue happened.
Maybe Scott Smith will chime in, he's the 340 guru!

[Cuda Cody]

   I bet @ScottSmith_Harms  knows

[ScottSmith_Harms]

It changed when they changed engine plants from Windsor Ontario Canada (orange) to Mound Road Michigan (blue). The engine assembly info was stamped on the face of the block. A 71 Windsor engine was stamped GW340Pxxxx and a 71 Mound Road engine was stamped GM340Pxxxx.

[Cuda Cody]

I learned something new today!   

[6bblgt]

the specific date is a difficult question to answer, but the "blue" engines started to appear in cars during March of '71

the date is going to vary based on the specific 340 engine and rate of use (and inventory control) at each plant
A, B & E-body engines - automatic & manual transmission engines - A/C & non-A/C engines - assembly plant: 1A, 1B, 1E & 1G engines

if you have your original engine - the GW340 "orange" VS GM340 "blue" stamping is the first place to look

[aussie]

Thanks guys, Yes the engine is not original to the car and the stamping on front just below the left head has one number which is just hard to make out. What I do know is the block was cast on 20 January 1971 (1.20.71) is orange with not a hint of blue colour to be found. The engine number is HM 340R  3_64 0130 and was trying to narrow down what it may be, trying to figure out when it was built.

[6bblgt]

..... The engine number is HM 340R  3_64 0130 .....

that's a '72 model year engine - it was originally painted "BLUE"

H = 1972 model year
M = Mound Rd. engine assembly plant Detroit, MI
340 = cu.in.
R = regular fuel
3_64 =
* 3564 = Sat.  5/1/71
* 3664 = Mon. 8/9/71
* 3764 = Wed. 11/17/71
* 3864 = Fri. 2/25/72
0130 = engine assembly sequence number

what is the partial VIN stamped on the block?

[6bblgt]

what are you planning to install it in?  What's the VIN?
does it have a broadcast sheet and door sticker?

steel or cast crank? cast crank started with HM340R 3911 8000 (Wed. Apr. 12, 1972)

[Shane Kelley]

I have a blue January 1971 motor. It has the 2.02 J heads also.

[6bblgt]

I have a blue January 1971 motor. It has the 2.02 J heads also.

3553 = Tues. 4/20/71 

[aussie]

Thanks for helping,  VIN 2R197713 on block near sump and don't know which crank is in it but it does have J heads. Engine was in the car when I got it and runs great, last owner did nothing to it except drive it less than 3000 miles in 15  years. She is trying to contact who she bought it from, so I can get more history on the car, no build sheet as i stripped the interior etc when I got it.   

[ScottSmith_Harms]

Like Dan said that 72 340 should have been blue originally. While it appears that it's always been orange I would wager that it has an older rebuild on it and that it was stripped to bare iron during the process and re-painted in orange. Completely bare iron is not an uncommon result of a good hot tanking or shot blasting. What I can't see on your block pics are the next 4 digits after HM340R which would be the 4 digit assembly date. Can you read them?

[aussie]

Yes I can read all but one number which is the 2nd in the sequence HM340R 3_64 0130,  VIN 2R197713 above sump pan, Block Casting Date 20 January 1971. I know the engine is not original to the car, just trying to find out the 2nd number which is very faint, looks a different number each time you look at it.