Chevelle V8 Cylinder Head Casting Numbers - 1964 through 1972

These head castings were used in various other models of the Chevrolet lineup such as the passenger car, Chevy II/Nova, Camaro and Corvette. Only Chevelle-specific information is listed here to conserve space. Some casting numbers are NOT listed as they may have been used in other models of the Chevrolet lineup but were NOT used in the Chevelle - such as the 1965 409cid heads #3830817 & #3852583 or 67 Camaro heads #3876775.

The casting number is probably the most significant feature on a cylinder head as it's the hardest to alter. The casting date is usually found near the casting number. Both are found under the valve cover be it a small block V8 (283/307/327/350) or big block Mark IV V8 (396/402/454).

It's important to remember the 'to' and 'from' dates listed may vary due to production lead time and stock inventories being depleted. For example just because a particular head casting may be listed as being used from January to April doesn't imply that the engine assembly plants discarded all pre-January heads or on the 1st of May discard all heads they had in inventory to begin using the newer design.

CHEVELLESTUFF  All Rights Reserved

CHEVELLESTUFF  All Rights Reserved

CHEVELLESTUFF  All Rights Reserved

Courtesy Chris Holcombe
Courtesy Chris Holcombe
Casting clocks. Note the 11 dots plus the number 0 indicating the particular hour of a shift the heads were cast.

Cylinder heads are normally date coded in the form of a letter for the month (see table below), two numbers for the day and a single number for the year.  For example, C259 indicates a date of March 25, 1969.

V8 Cylinder Head Casting Month Codes
A - JanuaryB - FebruaryC - MarchD - April
E - MayF - JuneG - JulyH - August
I - SeptemberJ - OctoberK - NovemberL - December

Caveats to production dates. Due to inventories, shipping schedules, etc. it is entirely possible that cylinder heads being phased out of production may still appear on Chevelles built after that time.

Head
Number
YearEngineHorsepowerValve Size
Int./Exh.
Combustion
Chamber cc.
Notes
37958961964283
327
195, 220
250
1.72/1.5059.669Used in 1964 and 1965.
37824611964
1965
1966
327
327
327
300
250, 300
275
1.94/1.5062.076Production ended approximately June of 1966 and replaced with #3890462. Casting symbol on exterior face of head is the infamous double-hump design.
CHEVELLESTUFF  All Rights Reserved
 1964
1965
1966
327
327
327
350
350
350
2.02/1.6062.0761966 is late March introduction.
37958961965283195, 2201.72/1.5059.669Casting symbol on exterior face of head is single centered pyramid on square block.
CHEVELLESTUFF  All Rights Reserved
38562081965396 3752.19/1.75108.989First square-port Mark IV head. Has spark plug shield boss.
38727021966396325, 3602.06/1.7298.427All oval-port applications. Has spark plug shield boss. It is debatable as to whether these plug shields were used on the Chevelle but the shields listed in Chevrolet parts books included the Chevelle application.
387385819663963752.19/1.72108.989All high performance square-port engine applications. Has spark plug shield boss.
38845201966
1967
283
283
195, 220
195
1.72/1.5060.530 CHEVELLESTUFF  All Rights Reserved
3890462 1966
1967

1966 **
1967
327
327

327
327
275
275

350
325
1.94/1.50
1.94/1.50

2.02/1.60
2.02/1.60
62.076
63.305

62.076
63.305
Similar to 3782461. Used from January 1966 through May 1967.
CHEVELLESTUFF  All Rights Reserved
39043901967396325, 3502.06/1.7298.427First head without spark plug shield boss. Used until January when replaced with #3909802.
39043911967 3963752.19/1.72106.8Used at least through May 1967 when replaced with #3919840.
CHEVELLESTUFF  All Rights Reserved
39098021967396325, 3502.06/1.72100.967January through April of 1967, with redesigned combustion chamber. June 1967 casting dates have been reported for this head.
39110321968307200 1.72/1.5069.629Used in 1968 only. Has temperature sending unit boss.
CHEVELLESTUFF  All Rights Reserved
39172151967
1968
396 325, 3502.06/1.72100.967First Mark IV oval-port with temperature sending unit boss, otherwise identical to #3909802. Production from May 1967 to May 1968.
39172911967
1968
3272751.94/1.5063.305Used in late 1967 (May/April) and all 1968. Identical to #3890462 except it has the temperature sending boss. The late 1967 unit has the temperature sending unit boss but is not tapped.
CHEVELLESTUFF  All Rights Reserved
3917291 1967
1968
3273252.02/1.6063.995Combustion chamber enlarged and valve guide boss diameter increased to accept the 2.02/1.60 valves.
CHEVELLESTUFF  All Rights Reserved
3917293 19683272501.72/1.5075.340Low compression, identical to #3884520 except for combustion chamber change and addition of temperature sending boss.
CHEVELLESTUFF  All Rights Reserved
39198401967
1968
1969
3963752.19/1.72106.8First Mark IV to have temperature sending boss. The late 1967 unit has the temperature sending unit boss but is not tapped. Identical to #3904391 except for temperature sending unit boss and two accessory bolt holes added.
CHEVELLESTUFF  All Rights Reserved
39198421969396375 (L89)2.19/1.84106.8Aluminum head with temperature sending unit boss, two accessory holes drilled and tapped, revised exhaust manifold surface. Two versions were used during 1968 (non-Chevelle) and 1969. The 1968 and early 1969 version had plugs in both ends of the cylinder head. Approximately June of 1969 one plug was eliminated.
39271851969
1970
3072001.72/1.5069.625Identical to #3884520 except has temperature sending unit boss. Three accessory bolt holes added to each end of the head and combustion chamber revised.
CHEVELLESTUFF  All Rights Reserved CHEVELLESTUFF  All Rights Reserved
39271861969
1970
350 3001.94/1.5063.305Similar to #3917291 & #3782461, but with temperature sending unit boss, three accessory holes and casting symbol was smaller.
CHEVELLESTUFF  All Rights Reserved
39310631969396325, 3502.06/1.72100.967 Similar to #3909802 & 3917215 with two accessory bosses above #3 (or #6) exhaust ports for air conditioning rear support bracket. Straight casting flashing.
39324411969
1970
350250, 255
250
1.94/1.5076.26Similar to #3927186 with redesigned combustion chamber.
CHEVELLESTUFF  All Rights Reserved
39470411969
1970
3503001.94/1.5063.305Similar to #3782461 with redesigned combustion chamber, addition of a temperature sending unit boss and three accessory holes on end.
CHEVELLESTUFF  All Rights Reserved
39642901969
1970
1970
396
402
454
325, 350
330, 350
360
2.06/1.72100.967Similar to #3931063 with spark plug seat changed to tapered, "peanut" plug but early castings had standard, "N" reach plug. Straight casting flashing.
39642911969

1970
396
427
402
454
375
425
375
450
2.19/1.88109.037Similar to #3919840 with spark plug seat changed to tapered, "peanut" plug but early castings had standard, "N" reach plug. Last closed chamber cast iron square-port head. Produced in both plug designs for service replacement of 1965 through 1969 applications.
CHEVELLESTUFF  All Rights Reserved
39734871971
1972
350
350
245, 270
165, 175
1.94/1.5075.47Similar to #3832441 & #3782461 with redesigned combustion chamber, addition of temperature sending unit boss, three accessory bolt holes added to end of head, tapered spark plug seat and different external identification symbol cast near the internal casting number.
CHEVELLESTUFF  All Rights Reserved
3973487X1972350165, 1751.94/1.5075.47Used only in late 1972 and overlapped production with #3998993.
CHEVELLESTUFF  All Rights Reserved
398633919713072001.72/1.5074.56Similar to #3884520 with redesigned combustion chamber, temperature sending unit boss and tapered spark plug seat.
CHEVELLESTUFF  All Rights Reserved
39938201971402
454
300
365
2.06/1.75113.060Cast iron, oval-port and similar to #3931063 with change to open-chamber design, redesigned intake and exhaust valve seats, and tapered spark plugs.
39940261971454 4252.19/1.88118.000Cast iron, square-port with tapered spark plug. Last Mark IV square-port with open chamber design.
399899119723071301.72/1.5074.56Similar to #3795896 with tapered spark plug, redesigned combustion chamber, and temperature sending unit boss. First head to use hardened valve seats for unleaded fuel.
CHEVELLESTUFF  All Rights Reserved
39989931972
1973
1973
350
307
350
165, 175
115
145, 175
1.94/1.5075.47Introduced mid-year (January) to replace #3973487X.
CHEVELLESTUFF  All Rights Reserved
39992411972 402
454
240
270
2.06/1.72113.06Similar to #3993820 with tapered spark plug seat.
3530491973454245*2.06/1.72113.06Used for all 1973 454 applications.
3338821974-75
1974
1975
350
400
400
All
150, 180
175
1.94/1.5075.47Similar to #3998993 with tapered spark plug seat.
3367811974
1975
454
454
235
215
2.06/1.72113.06Used for all 1974 and early 1975. Replace by #346236 mid-year 1975.
34623619754542152.06/1.72113.06Replaced #336781 mid-year 1975.

* The 1973 454 Corvette engine was rated at 270hp. Since this head has the same intake/exhaust and cc volume, it's not known why it is listed at 245hp for 1973.

** The L79 327/350 engine was never available in the Chevelle lineup in 1966; this cylinder head was used on the 1966 L79/350 in the Chevy II/Nova and Corvette.

CHEVELLESTUFF  All Rights Reserved
1966 Oval port head; notice tapped bosses for spark plug shields.

CHEVELLESTUFF  All Rights Reserved

CHEVELLESTUFF  All Rights Reserved

CHEVELLESTUFF  All Rights Reserved
CHEVELLESTUFF  All Rights Reserved

The top head is the 'lower horsepower' version (300hp and under) used on 67-68 327 applications with 1.94 intake and 1.50 exhaust while the bottom head is the performance version (325hp and higher) used on 67-68 327 applications with 2.02 intake and 1.74 exhaust. These happen to be casting #3917291 with 63.305 and 63.995 cc combustion chambers respectively.  Other 'pairs' of 327 heads 1.94 vs. 2.02 intake valve size and different combustion chamber sizes are found in other years with casting numbers 3782461 (64-66 model years) and 3890462 (66-67 model years).