1964 Chevelle
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V8 Exhaust Manifold Casting Numbers (Group 3.265)
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 | 1965 1966 |
283 283 327 |
195 195 275 |
1.96 | RH | Type 1. "Log"
type with rear outlet. No heat tube, no A.I.R. |
| 3840912 | 1965 1966 |
283 327 283 |
220 250, 300, 350 220 w/o A.I.R. |
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 |
