Casting numbers say which part a block or head is; the stamp and date code say when and where the engine was built. Start with the VIN for what the car left the factory with, then check the engine itself, since engines get swapped.
Where the numbers are and what they mean
Engine stamp pad — What: Stamped engine ID pad with displacement, assembly plant, date and sometimes a letter for high-performance/low compression; plus partial VIN stamp on 1968-up blocks.. Location LA: FACTORY: left front corner of the block, below the (left) cylinder head (1988 truck service manual; 1994-96 parts catalog). The 1964 318 in Fig. 4 is the A-engine 'poly' 318, not LA.. low-deck B 361/383/400 do not have that pad. First pass status: not_found. Chrysler Corp. 1964 Plymouth/Valiant Service Manual (factory): factory: https://archive.org/details/1964-plymouth-valiant-service-manual: p.5 'Vehicle and Engine Numbers' (Figs. 3-5); p.9-35 'Oversize and undersize engine component markings': ENGINE NUMBER: ... The 318 engine number contains the model, cubic inch displacement and serial number (Fig. 4). The numbers are stamped on a boss on the cylinder block as shown. [Fig. 4 photo shows 'V318-100001'] ... 318: .001 U/S crankshaft = Maltese Cross following engine serial number; .010 U/S = B following engine serial number; .020 O/S bores = A following engine serial number.; Chrysler Corp. 1970 Dodge Challenger/Dart Service Manual (factory), Group 9 Engine: factory: https://archive.org/details/70-dodge-challenger-dart-sm: OVERSIZE AND UNDERSIZE ENGINE COMPONENT MARKINGS (318/340): .001 U/S crankshaft R or M ... milled flat on number eight crankshaft counterweight; .010 U/S crankshaft RX or MX; .020 O/S cylinder bores 'A' following engine serial number; .008 O/S tappets 3/8 in. diamond shaped stamp - top pad - front of engine and flat ground on outside surface of each O/S tappet bore; .005 O/S valve stems 'X' milled pad adjacent to two 3/8 in. tapped holes on end of cylinder head.: p.9-94; Chrysler Corp. 1988 Dodge Trucks Service Manual (factory), Introduction 'Engine Serial Number': factory: https://archive.org/details/1988-dodge-trucks-service-manual-with-ocr: Introduction, Fig. 4: On 318 C.I.D. (5.2 liter) and 360 C.I.D. (5.9 liter) 8 cylinder engines, the engine serial number is located on the left front corner of the block, below the cylinder head.; Mopar 1994-1996 Dodge Light Truck and Van Parts Catalog (factory), General Information 'Engine Identification Numbers': factory: https://archive.org/details/1994Through1996MoparDodgeLightTruckAndVanPartsManualOCR1141Pages: INF-7, INF-8: 3.9L, 5.2L & 5.9L Engine Typical: 'B 318 1024 2579' = Model Year and/or Plant / Displacement / Date Code (1024 = Oct. 24) / Daily Sequence Number (Optional). Serial Number Pad Located: 5.2L, 5.9L Left Front of Block below Cylinder Head. Symbols: A = Oversize Cylinder Bore, E = Cast Crankshaft, H = Standard 4 BBL., HP = High Performance, K = Toluca Engine Plant, LC = Low Compression, M = Mound Road Engine, PC/R = Passenger Car Engine, S = Special Engine, T = Trenton Engine/Truck, W = Windsor Engine, X = O/S Valve Guide, DIAMOND = O/S Tappets, MALTESE CROSS = .001 U/S Crankshaft, X followed by MALTESE CROSS = .010 U/S Crankshaft.. Decode factory: Pad carries model-year/plant letter, displacement, 4-digit date code read as month+day (parts-catalog example 1024 = Oct 24), optional daily sequence number, plus symbols (HP, LC, A = .020 O/S bores, diamond = .008 O/S tappets, Maltese cross = .001 U/S crank, X + Maltese cross or B = .010 U/S crank).. Status note: The decode example is a 1990s truck stamp; 1960s-70s LA stamps may differ.
Engine stamp pad — What: Stamped engine ID pad with displacement, assembly plant, date and sometimes a letter for high-performance/low compression; plus partial VIN stamp on 1968-up blocks.. Location B RB: FACTORY: stamped on a boss/pad at the top front of the block beside the distributor (1964 photo covers 361/383 B and 426 RB wedge; 1970 Fig. 43 shows the 383-440 numbering pad at the top front). First pass status: not_found. Chrysler Corp. 1964 Plymouth/Valiant Service Manual (factory): factory: https://archive.org/details/1964-plymouth-valiant-service-manual: p.5 'Vehicle and Engine Numbers' (Figs. 3-5); p.9-35 'Oversize and undersize engine component markings': ENGINE NUMBER: The 170, 225, 361, 383 and 426 engine numbers contain the model, cubic inch displacement and manufacturing date, Figs. 3 and 5. The numbers are stamped on a boss on the cylinder block as shown. [Fig. 5 'Engine Number Location (361, 383 and 426)' photo: pad beside the distributor stamped 'V36 HP 7-22'] ... 361/383/413/426: .001 U/S crankshaft Maltese Cross, top pad - front of engine.; Chrysler Corp. 1970 Dodge Challenger/Dart Service Manual (factory), Group 9 Engine: factory: https://archive.org/details/70-dodge-challenger-dart-sm: Fig. 43 - Showing Location of External Engine Numbering Pad [photo: pad at the top front of the block] ... A Maltese Cross stamped on the engine numbering pad indicates ... .001 inch undersize ... A Maltese Cross with an X indicates .010 inch undersize journals. ... A diamond shaped marking stamped on the engine numbering pad indicates that some tappet bodies are .008 inch oversize.: 383-440 section p.9-52/53, 9-61. Decode factory: 1964: model-year letter + displacement + optional HP + month-day build date (photo 'V36 HP 7-22' = 1964 (V) 361 HP, July 22). Maltese cross = .001 U/S crank journals, X + Maltese cross = .010 U/S, diamond = .008 O/S tappets.. Still open: 1968-up partial-VIN stamp location and plant letters: not in these factory texts.
Engine stamp pad — What: Stamped engine ID pad with displacement, assembly plant, date and sometimes a letter for high-performance/low compression; plus partial VIN stamp on 1968-up blocks.. low-deck B 361/383/400 do not have that pad. First pass status: not_found. Chrysler Corp. 1970 Dodge Challenger/Dart Service Manual (factory), Group 9 Engine: factory: https://archive.org/details/70-dodge-challenger-dart-sm: [426 Hemi section] A diamond shaped marking stamped on the engine numbering pad indicates that some tappet bodies are .008 inch oversize. ... A Maltese Cross stamped on the engine numbering pad indicates that engine is equipped with a crankshaft which has one or more connecting rods and/or main bearing journal finished .001 inch undersize ... A Maltese Cross with an X indicates .010 inch undersize journals.: 426 section p.9-67 to 9-85. Factory summary: Factory confirms the Hemi carries an engine numbering pad with diamond (O/S tappets) and Maltese cross (U/S crank) marks. Pad LOCATION for the Hemi is not stated in the text read.. Scope: marks only; location still open
Engine stamp pad — What: Stamped engine ID pad with displacement, assembly plant, date and sometimes a letter for high-performance/low compression; plus partial VIN stamp on 1968-up blocks.. low-deck B 361/383/400 do not have that pad. First pass status: not_found. Chrysler Corp. 1998 Ram Truck 1500-3500 Service Manual (factory), Group 9 Engine: factory: https://archive.org/details/98-dodge-ram-truck-sm: 9-59, 9-93 Fig. 2: The engine serial number is stamped into a machined pad located on the left, front corner of the cylinder block. ... 'X M 5.9L T XXXX XXXXXXXX': X = Last Digit of Model Year; M = Plant - M Mound Road, S Saltillo, T Trenton, K Toluca; 5.9L = Engine Displacement; T = Usage - T Truck; XXXX = Month/Day; XXXXXXXX = Serial Code - Last 8 Digits of VIN No.; Chrysler Corp. 1998 Ram Truck 1500-3500 Service Manual (factory), Group 9 Engine: factory: https://archive.org/details/98-dodge-ram-truck-sm: 5.9L engine specifications: .020 O/S cylinder bores 'A' following engine serial number; .008 O/S tappets 3/8 in. diamond-shaped stamp top pad - front of engine and flat ground on outside surface of each O/S tappet bore; .005 O/S valve stems 'X' milled pad adjacent to two 3/8 in. tapped holes on each end of cylinder head; .001 U/S crankshaft R or M milled flat on number three crankshaft counterweight.; Mopar 1994-1996 Dodge Light Truck and Van Parts Catalog (factory), General Information 'Engine Identification Numbers': factory: https://archive.org/details/1994Through1996MoparDodgeLightTruckAndVanPartsManualOCR1141Pages: INF-7, INF-8: Serial Number Pad Located: 5.2L, 5.9L Left Front of Block below Cylinder Head.. Location: FACTORY: machined pad on the left front corner of the block, below the cylinder head.. Decode factory: Last digit of model year + plant letter (M Mound Road, S Saltillo, T Trenton, K Toluca) + displacement + usage letter (T truck) + MMDD build date + last 8 digits of the VIN (1998 Ram service manual).