V8 Exhaust Manifold Casting Numbers - 1964 through 1972

These exhaust manifold 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.

All factory exhaust manifolds are cast iron. Some may not have casting dates and the location of dates and/or casting numbers may vary from year to year.

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 exhaust manifold casting may be listed as being used from January to April doesn't imply that the engine assembly plants discarded all pre-January exhaust manifolds or on the 1st of May discard all exhaust manifolds they had in inventory to begin using the newer design. Many manifolds were used in multiple years.

Exhaust manifolds 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 Exhaust Manifold Casting Month Codes
A - January B - February C - March D - April
E - May F - June G - July H - August
I - September J - October K - November L - December

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

Manifold
Number
Year Engine Horsepower Outlet
Size
Outlet
Side
Notes
3834947 1964


1965


1966
283
327
283
327
283
327
195, 220
250
195, 220
250, 300, 350
195, 220
275
2.026 LH First "log" type used on Chevelle.



w/o A.I.R.
w/o A.I.R.
3840715 1964 327 300, 365. 2.46 LH One year only design. "Log" type with generator bracket, bell bottom, high performance.
3840912 1964
1965
1966
283
283
283
327
195
195
195
275
1.96 RH Type 1. "Log" type with rear outlet. No heat tube, no A.I.R.
3840912 1964

1965

1966
283
327
283
327
283
220
250
220
250, 300
220
1.96 RH Type 2. Identical to type 1 except it was drilled for heat tube.
3840912 1964 327 300 1.96 RH Type 3. Outlet machined to a larger bell bottom shape, rear outlet and drilled for heat tube.
3868874 1965
1966
1967
396
396
396
375
325, 360, 375
325, 350, 375
2.526
2.526
2.526
RH 1965 and 1966/67 have same casting numbers but 1965 units do not have boss for A.I.R. but only 1966/67 Chevelles that used A.I.R. were drilled and tapped.
3869925 1965 396 375 2.526 LH Bosses present for heat tube, no A.I.R.
3872729 1966 283
327
195, 220
275
2.026 LH Identical to #3834947 except drilled & tapped for A.I.R.
3872730 1966


1967


1968
283
327
283
327
307
327
195, 220
275
195
275, 325
200
250, 275, 325
1.96 RH Identical to #3840912 (type 2) except drilled & tapped for A.I.R.
1967 - w/A.I.R.

1968 - S/T w/A.I.R.
3872730 1966 283 220 1.96 RH Same as above except drilled for heat tube.
3883999 1966 396 325, 360, 375 2.526 LH One year only, used until June, 1966. Has A.I.R. bosses but only those equipped with A.I.R. are drilled & tapped.
3892679 1967

1968
283
327
307
327
195
275, 325
200
250, 275
2.026 LH Without A.I.R.

1968 - A/T w/o A.I.R
3892683 1967

1968
283
327
307
327
195
275, 325
200
250, 275, 325
2.026 LH Same as #3892679 except drilled & tapped for A.I.R.
1968 - S/T w/A.I.R.
3893608 1967

1968
283
327
307
327
195
275, 325
200
250, 275
1.96 RH Casting changed from #3840912 sometime late 1966 or early 1967 but date not known. Non-A.I.R.
3902401 1966
1967
396
396
325, 360, 375
325, 350, 375
2.526 LH June, 1966 through March, 1967 - cast from June, 1966 through December, 1966. Used for both A.I.R. and non-A.I.R.
3909879 1967
1968
1969

1970
396
396
396
427
402
454
325, 350, 375
325, 350, 375
325, 350, 375
425 (COPO)
330, 350, 375
360, 450
2.526 LH Replaced #3902401 in March, 1967.
3909880 1967 396 325, 350, 375 2.526 RH Used from approximately January through June of 1967.
3916178 1967
1968
1969

1970
396
396
396
427
402
454
325, 350, 375
325, 350, 375
325, 350, 375
425 (COPO)
330, 350, 375
360, 450
2.526 RH Same as #3909880 with minor interior & exterior casting changes. Entered production in early June, 1967.
3932376 1969
1970
350
307
350
250, 255, 300
200
250, 300
1.96 RH "Log" type. Identical to #3946826 except not drilled & tapped for A.I.R. A/T w/o A.I.R.
3942527 1969 307
350
200
250, 255, 300
2.026 LH Identical to #3942529 except drilled & tapped for A.I.R. S/T w/A.I.R.
3942529 1969

1970
307
350
307
350
200
250, 255, 300
200
250, 300
2.026 LH Identical to #3942527 except not drilled & tapped for A.I.R. A.T w/o A.I.R.
3946826 1969 307
350
200
250, 255, 300
1.96 RH Identical to #3932376 except drilled & tapped for A.I.R. A/T w/A.I.R.
3959562 1972 307
350
130 NB2
165, 175 NB2
2.026 RH Identical to #3973432 except drilled & tapped for A.I.R. NB2 equipment required on California vehicles, A.I.R. system and camshaft with longer valve overlap.
3973432 1971

1972
307
350
307
350
200
245, 270
130 w/o NB2
165, 175 w/o NB2
2.026 RH Casting #3959562
3989041 1972 307
350
115
145, 175
2.026 LH Identical to #3989403 except drilled & tapped for A.I.R. A/T w/A.I.R.
3989043 1971

1972
307
350
307
350
200
245, 270
130
165, 175
2.026 LH Identical to #3989401 except not drilled & tapped for A.I.R. A/T w/A.I.R. Casting #3989401 after 10/19/71.
3989310 1971

1972
402
454
402
454
300
365
240
270
2.526 RH  
3989343 1971

1972
402
454
402
454
300
365
240
270
2.526 LH