Date Codes

409forever

Well Known Member
Supporting Member 2
Looking for info on the date codes on a 348/409 specifically 65 409 with 2 digit date code on the heads and a single date code on the block
Heads 8 4 and 8 7 --These are 817 Heads

Block 5 -- cast part # 656 build date 0122 (stamped on front right side block)
When I look up this info all I see are multiple #'s rather than single and double #'s
Thanks In advance
 

409forever

Well Known Member
Supporting Member 2
Thanks
So theses heads could be either 1964 or 1965 because the year is not noted
the block also is puzzling could that be 5th day of the year being 1965 since the 656 block was only 65 and the build date 0122 ?
 

unclebrad

Active Member
Hope it's ok to jump onto this thread with my date codes question. I'll start a new one if that would be more appropriate.

Three questions, actually...

One -
Where is the location of the date code on this engine with the CFD casting in the location where date code should normally be?
(rear passenger side, based upon what I have been reading so far)

Two-
I am told that this is a 1963 engine but is there a stamp or casting that actually tells what year this engine is?

Three-
What is the stamped number to the left of the Suffix Code on the Front Passenger side? (and is it something that can be decoded?)

Note: this is an X Block engine.

Front Passenger Side 1.jpg
Rear Drivers Side 1.jpg
Rear Passenger Side 1.jpg
 

unclebrad

Active Member
Thanks!

So, that is the date code on the FRONT of the engine? Is that where they located it on the CFD engines?

I'm still confused about how you can tell the year though.

Any ideas about the "serial number" to the left of the Suffix code?

BTW, heddrik, based upon the charts here, it was originally a 400 HP engine with a single 4bbl, but now it has dual quads on it, which I think pushes it to 425HP?

BTW #2, this is the engine that was advertised here by CashGuzzler a couple weeks ago. I got hold of the owner again and we started talking about safe shipping options, but then his (very good) friend, who is known here as CashGuzzler offered to drive the engine down to the SF Bay Area, from N. Seattle, just as one of those things friends do for friends. I have a cousin in the way north of California, and said I could meet him there to save him about 6 hours, and that's what we did!
Next thing to do is get a transmission that will handle this monster (thinking 700r4) and then swap out the tired 348 and leaky th350 in the Cameo.
 

oldskydog

Well Known Member
Supporting Member 10
The numbers to the left of the suffix code are the engine assembly date, not the casting date. The 293 is the casting date expressed as a "Julian' calendar" day of the year (1-365).
The model year is determined by the casting number in conjunction with the Julian date as the casting number changed every year in 409 production.
 

IMBVSUR?

Well Known Member
Supporting Member 2
Thanks!

So, that is the date code on the FRONT of the engine? Is that where they located it on the CFD engines?

I'm still confused about how you can tell the year though.

Any ideas about the "serial number" to the left of the Suffix code?

BTW, heddrik, based upon the charts here, it was originally a 400 HP engine with a single 4bbl, but now it has dual quads on it, which I think pushes it to 425HP?

BTW #2, this is the engine that was advertised here by CashGuzzler a couple weeks ago. I got hold of the owner again and we started talking about safe shipping options, but then his (very good) friend, who is known here as CashGuzzler offered to drive the engine down to the SF Bay Area, from N. Seattle, just as one of those things friends do for friends. I have a cousin in the way north of California, and said I could meet him there to save him about 6 hours, and that's what we did!
Next thing to do is get a transmission that will handle this monster (thinking 700r4) and then swap out the tired 348 and leaky th350 in the Cameo.


Good deal on finding a motor. A later trans may have more strength capability and if you don't mind using a stand alone controller that would be fine. Keep in mind though that if I remember right, this is going into a truck. You are not going to get all that power to ground most likely so don't kill yourself on the trans. A 700r4 can be built to handle much more than you have and lockup is simply a 12 volt power wire. I prefer the simplicity of the 700's. Who is going to build your trans, or are you going to purchase one from one of these tans sites?
 

unclebrad

Active Member
Oh boy. I'm as confused as ever about the julian calendar.
I get the "three digits = the day of the year" thing, but how the heck are you seeing the actual year? (I am not questioning the truth of what you are telling me. I am just curious about the process.)

I think you are talking about the T1129 numbers just in front of the QA, yes? If I understand it right, those are the assembly date numbers.

But, in the picture I posted, there is a whole set of numbers stamped to the left of the T1129QB stamping. (You have to look close to see them.)
Do you know what those are? And do they contain additional information?
 
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63impalass409

Well Known Member
Supporting Member 2
Those are the vin of the car it came in. You can tell the year by the casting number which is the raised set of numbers on back of motor right above bell housing flange on drivers side. 068 is 62, 814 is 63 ,422 is 64 ,656 is 1965 . Don't always assume from passenger side front engine stamp is original and what motor is as there is a lot of people re stamping blocks to pass it off as something it's not and if it's been decked and re stamped the broach marks will be gone. In fact I just saw a joker trying to pass off a 656 1965 block as a QB stamped 425 hp short block when in fact there where no QB stamps in 65 as they all started with a J in 65 such as JA JB JC. But anyways wrong stamp and it's a truck block with the cylinder notches and front passenger holes are drilled and tapped for truck mounts and he is advertising it as a 425hp short block ( NOT)
 
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