Help with 409 number identification

[57Chevy_409]

Hi Folks. I've been struggling with this for awhile now, but so far here is my interpretation of what my 409 engine is:

1. 1964 since casting is 3844422 and has “x” On Block.
2. CFD casting indicates that it came from the Central Foundry Division.
3. By the Julian Date Code "233" (leap year) it was manufactured August 20, 1964.

Did I get this correct so far? Is there any other information that I can extract from the numbers. Thanks!

 

[409forever]

What about the stamped # on the front passenger side should be 2 different #s one the last 8 of vin of car it was from and the last series of # would be from engine plant in Tonawanda NY

 

[427John]

Also does it have the compression notch since could also be a truck block?

 

[57Chevy_409]

I have not been able to locate a suffix code as of yet, but I was told that it was a "QG" which was for a 340HP Pass. Car.

 

[64ss409]

I believe the Julian date of 233 on a 422 block would probably be August 21, 1963. The Julian date on my 422 block in my 64 is 155. My car was built the 1st week of October, 1963.

 

[DaveN]

Julian date is only the day of the year 001 is Jan 1 and goes up to the end of the year leap year adds 1 day into the julian calendar every 4 years

 

[57Chevy_409]

Still can't find the typical suffix code, but I think that is because it came from the Central Foundry Division (marked "CFD") rather than the Tonawanda plant. The original machine shop (Elby's Automotive Machine Shop in Dublin, CA) that rebuilt the engine on 2/2/2012 had made a note on the original receipt saying that it was a 409 340 HP with 10:1 Compression (Hydraulic Lift Camshaft) which corresponds to a passenger car. It was bored .060 over. A couple of years ago, my friend (a retired machinist) found this engine, tore it apart and checked the build. He then added an ISKY Racing Cam and a RAB Serpentine kit and got the engine up and running. Eventually, this will get dropped into my 1957 Chevy Bel Air, 2-door Hardtop.

 

[BSL409]

Most likely the block was decked so they are gone

 

[409forever]

Hi Folks. I've been struggling with this for awhile now, but so far here is my interpretation of what my 409 engine is:

1. 1964 since casting is 3844422 and has “x” On Block.
2. CFD casting indicates that it came from the Central Foundry Division.
3. By the Julian Date Code "233" (leap year) it was manufactured August 20, 1964.

Did I get this correct so far? Is there any other information that I can extract from the numbers. Thanks!

The Julian date on the block was the date it was cast not built
if you can get a picture of the pad on the passenger front side and hopefully see the stamped # that will give you the date it was assembled
but as BSL409 said it could have been decked at some time

 

[blkss64]

I think there maybe a discussion about this topic in a previous post. I think it was brought up that law enforcement agencies use acid or another product to try and find the number that was stamped on the pad. I may be wrong on this. I am sure the more tech savvy people on this forum may have better information.

 

[57Chevy_409]

The Julian date on the block was the date it was cast not built

My mistake on the "casting" date.
If I am looking at the correct location, the pad on the passenger front side looks clean. I can't imagine decking would remove the entire number?
I was under the impression that you guys just needed a picture of the shadow cast by one of these engines to tell everything there is about it.

 

[Don Jacks]

It could have been built from a service replacement block.They had no numbers on tthe pad either.

 

[57Chevy_409]

This is worse than looking for the VIN on the frame of my '49 F1. I guess it'll remain a mystery.

 

[427John]

Dang that pad looks like someone took a grinder to it, it may just be the photo but it looks like there are divots from a grinding wheel. Run your finger across the top of that and feel the surface, if it was decked and that removed the numbers or if it was never stamped to begin with it will be a perfectly flat machined surface,if its an uneven surface with divots in it then someone may have used an angle grinder to obliterate the numbers something that was commonly done back in the day when a car was stolen, after all this time and changes of hands there is no telling what this engine has seen. I've seen a block or 2 that has had that done to it.

 

[32witha409]

Looks like there is paint under the new paint and something on the pad under the paint. I would razor blade the paint off and see what's under it.

 

[57Chevy_409]

I was thinking of removing the paint, but I am guessing that I will just find a smooth surface. I see the divots that you are referring to but I also see some casting marks as well (more apparent in the higher res pic). Not sure if this was done with a hand-held grinder but who knows. Here's another angle:



One other clue is that the original owner or machinist circled the suffix code "QG" on a copy of the 348/409 Suffix Codes. Wouldn't this have been information contained in this number?

 

[409forever]

looks rough but as 32witha409 Fine sand paper and a razor blade to clean the area would defiantly clarify if any number can be seen
as blkss64 stated the law enforcement does use an acid to bring out any remnant of a stamped number in metal

 

[57Chevy_409]

Thanks everyone for the help. I may try removing some paint at some point, but now looking more closely, I'm thinking that the decking is a great theory. I didn't realize that the stamping pad appears to be in exactly the same plane as the cylinder head surface. The original machine shop receipt shows resurfacing of the heads but nothing extra on the block. I suppose also a factory replacement block is also possible.

 

[Iowa 409 Guy]

looks rough but as 32witha409 Fine sand paper and a razor blade to clean the area would defiantly clarify if any number can be seen
as blkss64 stated the law enforcement does use an acid to bring out any remnant of a stamped number in metal

I tried raising one with muradic acid.. no luck for me.

 

[427John]

The reason the acid trick works is due to the localized compression of the metal beneath the stamp that makes it less porous and more resistant to the acid,but it is localized and if it is ground or milled deep enough you will get thru it and the trick won't work anymore.