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Holden HK to WB Engine Numbers
Holden HK to WB Engine Numbers Engine Numbers The are several numbers stamped or cast on a block that identify the capacity of the motor and the…
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Engine Numbers
The are several numbers stamped or cast on a block that identify the capacity of the motor and the vehicle it was installed in.
Prefix:
This refers to the identification of the engine. For a variety of reasons, engines need to be correctly identified, and it is this prefix which clarifies areas such as capacity, compression ratio, transmission, etc. The location of the engine number prefix varies depending on the type of engine.
- On all L6 (in-line 6 cylinder) engines, the prefix can be found stamped on a pad on the right (viewed from the rear) side of the engine block above the engine mount
boss. - On 307, 327 and 350 cubic inch VB engines, it is located on a pad in front of the right (viewed from the rear) side cylinder head on the block.
- On 253, 308, 4.2 litre and 5.0 litre VB engines, the prefix is stamped on a pad above the engine mounting on the left (viewed from the rear) side of the block.
Block:
Each engine block has a casting number integral with metal castings for identification purposes. The block casting number can tell you important things likestandard bore diameter & stroke length, performance characteristics, and in the case of a Chevrolet V8 block, the crankshaft journal size and very often but not always the type of main bearing caps (ie two or four bolt).
- On all L6 engines, the casting number is located on the left (viewed from the rear) side of the block, just forward of the engine mounting boss
- On all 307,327 and 350 cubic inch engines, it is located on the left (viewed from the rear) top rear surface of the block near the bell housing attachment.
- On 253, 308, 4.2 litre and 5.0 litre V8 engines it is located on the left (viewed from the rear) side of the block slightly above and forward of the starter motor mounting pad.
Head:
- All L6 cylinder heads can be identified with the engine complete. The casting number is to be found on the top left (viewed from the rear) side toward the front of the engine. A locationg ear on the rocker cover gasket will need to be removed to expose the full casting number.
- All V8 engines require the rocker covers to be removed to expose the number.
Abbreviations:
Most of these require no further explanation, however lu=limited use and uu=uncertain usage do. These terms are limited to the HK, HT, HG and HQ models. The rules of Series Production racing in the 1960s demanded that vehicles involved in this motor sport had to compete in showroom stock condition. This was the sale reason why Model Number 81837 was created. This vehicle enabled GMH to successfully compete in motor sport despite the parent company world-wide ban on motor sport involvement
lu=limited use - means exactly what it says. Certain parts used in the manufacture of cars were available ‘officially’ for very short periods of time. This satisfied the rules and as a result, these effectively ‘modified’ vehicles were eligible for competition.
uu=uncertain usage - is a term used where no one, not even GMH can completely clarify the correct usage of these parts, Vehicles exist in original condition with these variations, and documentation exists to support this, sometimes only in very sketchy form.
| HK Engines | ||||
|---|---|---|---|---|
| Engine | Type | Comp. Ratio | Power | Eng No. Prefix |
| 161 HC | L6 | 9.2:1 | 114 (85) @ 4400 | 161H |
| 186 | L6 | 9.2:1 | 126 (94) @ 4200 | 186P |
| 186S* | L6 | 9.2:1 | 145 (108) @ 4600 | 186S |
| 307 | V8 | 8.75:1 | 210 | 307 |
| 327 | V8 | 8.75:1 | 250 | 1st type 327xxxxxTxxxxH5 |
| 327 | V8 | 8.5:1 | 235 | 2nd type (Any other 327 prefixed engine not represented as per above is from a GMH built Pontiac, Chevrolet etc.) 327xxxxxKxxxxH |
| *HK with optional 186S 2bbl. carb |
| HT Engines | ||||||
|---|---|---|---|---|---|---|
| Engine | Type | Bore | Stroke | Comp. Ratio | Power | Eng No. Prefix |
| 161 HC | L6 | 9.2:1 | 114bhp (85kw) @ 4400 | 161H | ||
| 186 | L6 | 9.2:1 | 130bhp (97kw) @ 4400 | 186P | ||
| 186S* | L6 | 9.2:1 | 145bhp (108kw) @ 4600 | 186S | ||
| 253 | 253L | |||||
| 253 | V8 | 3.625” | 3.062” | 9.0:1 | 185bhp (138kw) at 4400rpm | 253H |
| 307 | V8 | 3.875” (98.4mm) | 3.25 inches (82.6mm) | 8.75:1 | 210bhp (157kw) at 4600rpm | 307 |
| 308 | V8 | 4.00” (101.6mm) | 3.00” (77.8mm) | 9.0:1 | 240bhp (179kw) at 4000rpm | 308H |
| 350 | V8 | Pagewood only | ||||
| 350 | V8 | 10.25:1 | 300 | 350M (manual) | ||
| 350 | V8 | 9.0:1 | 275 | 350A (auto) | ||
| *HT with optional 186S 2bbl. carb |
| HG Engines | |||||||
|---|---|---|---|---|---|---|---|
| Engine | Type | Bore | Stroke | Comp. Ratio | Power | Eng No. Prefix | Ident. Code |
| 161 HC | L6 | 3.375” | 3.00” | 9.2:1 | 114bhp (85kw) @ 4400 | 161H | |
| 186 | L6 | 3.625” | 3.00” | 9.2:1 | 130bhp (97kw) @ 4400 | 186P | |
| 186S* | L6 | 3.625” | 3.00” | 9.2:1 | 145bhp (108kw) @ 4600 | 186S | |
| 202 LC | L6 | 3.62” | 3.25” | 7.8 : 1 | 129bhp (96kw) @ 4400 | 202H late HG High Compression | GL |
| 202 HC | L6 | 3.62” | 2.25” | 9.4 : 1 | 135bhp (101kw) @ 4400 | 202L late HG Low Compression | GM |
| 253 LC | V8 | 3.625” | 3.062” | 253L | |||
| 253 HC | V8 | 3.625” | 3.062” | 9.0:1 | 185bhp (138kw) at 4400rpm | 253H | |
| 307 | V8 | 3.875” (98.4mm) | 3.25 inches (82.6mm) | 8.75:1 | 210bhp (157kw) at 4600rpm | 307 | |
| 308 | V8 | 4.00” (101.6mm) | 3.00” (77.8mm) | 9.0:1 | 240bhp (179kw) at 4000rpm | 308H | |
| 350 | V8 | 4.00” (101.6mm) | 3.48” (88.39mm) | 10.25:1 | 300bhp (224kw) at 4800rpm | 350M (manual) | |
| 350 | V8 | 4.00” (101.6mm) | 3.48” (88.39mm) | 9.0:1 | 275bhp (205kw) at 4800rpm | 350A (auto) | |
| *HG with optional 186S 2bbl. carb |
| HQ - WB Engines HQ Series 1971 to 1974 | |||||||
|---|---|---|---|---|---|---|---|
| Engine | Type | Bore | Stroke | Comp. Ratio | Power | Eng No. Prefix | Ident. Code |
| 173 cu. ins. | L6 | 3.50” | 3.00” | 8.3 : 1 | 112bhp (84kw) @ 4400 | QE | E |
| 173 cu. ins. | L6 | 3.50” | 3.00” | 9.4 : 1 | 118bhp (88kw) @ 4400 | QD | D |
| 202 cu. ins. | L6 | 3.62” | 3.25” | 7.8 : 1 | 129bhp (96kw) @ 4400 | QM | M |
| 202 cu. ins. | L6 | 3.62” | 2.25” | 9.4 : 1 | 135bhp (101kw) @ 4400 | QL | L |
| 253 cu. ins. | V8 | 3.62” | 3.06” | 8.0 : 1 | 174bhp | QS | S |
| 253 cu. ins. | V8 | 3.62” | 3.06” | 9.0 : 1 | 185bhp | QR | R |
| 308 cu. ins. | V8 | 4.00” | 3.06” | 9.0 : 1 | 250bhp | QT | T |
| 350 cu. ins. | V8 | 4.00” | 3.48” | 8.5 : 1 | QU | U | |
| Engine Serial Number Stamping Location L6 - On Pad above Engine Mounting Bosses RH side of engine. V8 - 253 & 308 cu. in - On Pad at top front LH side of Cylinder Case. V8 - 350 cu. in. - On Pad RH side top surface of Cylinder Case, front of Cylinder Head Note: The Statesman Engines carry an additional prefix of “11” preceeding the Alphabetical Prefix |
| HJ Engines 1974 to 1976 | |||||||
|---|---|---|---|---|---|---|---|
| Engine | Type | Bore | Stroke | Comp. Ratio | Power | Eng No. Prefix | Ident. Code |
| 173 cu. ins. | L6 | 3.50” | 3.00” | 8.3 : 1 | 112bhp (84kw) @ 4400 | QE | E |
| 173 cu. ins. | L6 | 3.50” | 3.00” | 9.4 : 1 | 118bhp (88kw) @ 4400 | QD | D |
| 202 cu. ins. | L6 | 3.62” | 3.25” | 7.8 : 1 | 129bhp (96kw) @ 4400 | QM | M |
| 202 cu. ins. | L6 | 3.62” | 2.25” | 9.4 : 1 | 135bhp (101kw) @ 4400 | QL | L |
| 253 cu. ins. | V8 | 3.62” | 3.06” | 8.0 : 1 | 174bhp | QS | S |
| 253 cu. ins. | V8 | 3.62” | 3.06” | 9.0 : 1 | 185bhp | QR | R |
| 308 cu. ins. | V8 | 4.00” | 3.06” | 9.0 : 1 | 250bhp | QT | T |
| Note: The Statesman Engines carry an additional prefix of “11” preceeding the Alphabetical Prefix |
| HX Engines 1976 to 1977 | ||||||
|---|---|---|---|---|---|---|
| Engine | Type | Bore | Stroke | Comp. Ratio | Power | Ident. Code |
| 3300 engine, 3.298lt, man trans, 1976 - 1977 | L6 | 118bhp (88kw) @ 4000 | XQL | |||
| 3300 engine, 3.298lt, auto trans, 1976 - 1977 | L6 | 109bhp (81kw) @ 3900 | XQL | |||
| 3300 engine, 3.298lt, low comp, 1976 - 1977 | L6 | 75kw | XQM | |||
| 4.2L engine, 4.142lt, 1976 - 1977 | V8 | 3.625” (88.8mm) | 3.062” (75.0mm) | 9.4:1 | 120kw | QR |
| 5.0L engine, 5.044lt, 1976 - 1977 | V8 | 4.0” (101.6mm) | 3.062” (75.0mm) | 9.7:1 | 161kw | QT |
| HZ Series Engines 1977 to 1980 | ||||||
|---|---|---|---|---|---|---|
| Engine | Type | Bore | Stroke | Comp. Ratio | Power | Ident. Code |
| 3300 engine, auto 3.298lt, 1977-1980 | L6 | 118bhp (88kw) @ 4000 | XQL,ZL | |||
| 3300 engine, man 3.298lt, 1977-1980 | L6 | 109bhp (81kw) @ 3900 | ||||
| 4.2L engine, 4.142lt, 1977-1980 | V8 | 3.625” (88.8 mm) | 3.062” (75.0mm) | 9.4:1 | 120kw | QR,ZR |
| 5.0L engine, 5.044lt, 1977-1980 | V8 | 4.0”(101.6 mm) | 3.062” (75.0mm) | 9.7:1 | 161kw | QT,ZT |
WB Statesman DeVille and Caprice 1980
Engine
Type
Bore
Stroke
Comp.
Ratio
Power
Ident.
Code
5.0L engine, 5.044lt, 1980
V8
117kw (single exhaust)
126kw(dual exhaust)
WT
BLOCK CASTING NUMBERS
You can actually find the exact day on which that engine was cast by finding the date code on the engine block. This will be located on the very top front of the engine block near where the water pump bolts on (just forward of the front edge of the inlet manifold). Just behind the top of the timing casing/water pump. It will be a 3 or 4 digit code consisting of several numbers and at least one letter. There will also be a little clock symbol just near it. This clock actually signifies the exact time of day that the block was cast. Casting dates are very simple to decode The first on or two letters are the day of the month.
The letter is the month
A = January
B = February
C = March
D = April
E = May
F = June
G = July
H = August
J = September
K = October
L = November
M = December
(I is not used so H=August then J=September). The last number is the year. 2=72, 3=72 etc. Earlier blocks (which have a different prefix on the engine number [253H]) will have the month before the day in the date code. Later blocks such as 82, 83 etc can be distinguised from 72, 73 by having 4.2 cast on the side instead of 253. There are also other differences as well but that is a very simple one.
Also see: Holden 6 Cylinder Engine - Background To Identification | Holden Engine Identification Guide | Holden Engine Numbers
