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Old 04-27-2012, 04:52 PM
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Originally Posted by Big_rig
I'm not sure what you mean by suffix. If you could explain, I would like to know all I can about this engine before I tear into it and put it in my truck.
The numbers I have are;

Block casting: 3788378
Head casting: 3824435
Pad behind distributor: S19754
Rear passenger side: CON3 A 30 2

That's all the numbers I can see without stripping all the paint off the block for a closer look. If those numbers have the suffix you're talking about please do fill me in. Thanks.
OK, "CON3" is a foundry ID code, it's no help in ID'ing the engine.

"A 30 2" is a date code: Jan 30 of a year ending in 2. If this is a 250, that would be 1972.

The suffix (also called the "application" code) will be in a string of letters and numbers. The string is usually a letter followed by a date code, followed by 1, 2 or 3 letter code. This is found in the area where you were looking near the distributor, above the fuel pump (prolly near where you found "S19754"). The suffix string of letters/numbers are always stamped in, not cast into the block like the date code or foundry ID code.

Some suffix codes for '72:

CAL - 250cid w/3-speed manual (Taxi)
CBA - 250cid w/3-speed manual and NB2
CBG - 250cid w/3-speed manual
CBJ - 250cid w/Powerglide
CBK - 250cid w/Powerglide (Taxi)
CDL - 250cid w/Powerglide and A.I.R.
CDM - 250cid w/3-speed manual and A.I.R.
CSD - 250cid w/Powerglide and NB2
Note- "NB2" refers to exhaust emissions

There may also be a partial VIN number stamped in a separate string of numbers near the suffix string. If your block is missing the suffix and partial VIN, there's no way to know what the engine might have come in originally, unless there were other bolt-on clues like a carb w/a governor on it (would be on a heavy truck or bus), or if it had a large bellhousing and a HD "granny low" trans (also HD truck/bus application). If the crankshaft has a pilot bushing in it, that would mean it had been used w/an auto trans- although this could have been added later.

I don't know what the "S19754" stands for. Maybe someone else can tell you more about this.
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