1978 Firebird Engines
| UPC Code | Type | Source | Displ cid | Bore & Stroke | Carb | Comp | HP/RPM Net | Torque/RPM | VIN | Engine Block code(s) | UPC | Transmission | Axle | Opt Axle | Base | Esprit | Formula | Trans Am | Notes |
| LD5 | V-6 | Buick | 231 | 3.80 x 3.40 | 2 bbl | 8.0:1 | 105@3400 | 185@2000 | A | EA, EC, EE | MM3 | 3 Speed Manual | | | S | S | n/a | n/a | Not available with 3 speed in Californa or High Altitude |
| MX1 | 3-Speed Turbo Hydramatic Transmission (Turbo 350) | A | A | n/a | n/a |
| LG3 | V-8 | Chevrolet | 305 | 3.74 x 3.48 | 2 bbl | 8.4:1 | 145@3800 | 245@2400 | U | TH, TJ, TK, 3N | MM4 | 4 Speed Wide Ratio Manual Transmission | | | A | A | S | n/a | Not available with High Altitude Package |
| 135@3800 | 240@2000 | MX1 | 3-Speed Turbo Hydramatic Transmission (Turbo 350) | A | A | A | n/a |
| LM1 | V-8 | Chevolet | 350 | 4.00 x 3.48 | 4 bbl | 8.2:1 | 170@3800 | 270@2400 | L | HF, HJ, HL, HR, 3T | MM4 | 4 Speed Wide Ratio Manual Transmission | | | A | A | A | n/a | Not available with 4 Speed in Californa or High Altitude |
| 160@3800 | 260@2400 | MX1 | 3-Speed Turbo Hydramatic Transmission (Turbo 350) | A | A | A | n/a |
| L78 | V-8 | Pontiac | 400 | 4.125 x 3.75 | 4 bbl | 7.7:1 | 180@3600 | 325@1600 | Z | YA, YU | MX1 | 3-Speed Turbo Hydramatic Transmission (Turbo 350) | | | n/a | n/a | A | S | Not available in Californa or High Altitude |
| W72 | V-8 | Pontiac | 400 | 4.125 x 3.75 | 4 bbl | 8.1:1 | 220@4000 | 320@2800 | Z | WC | M21 | 4 Speed Close Ratio Manual Transmission | | | n/a | n/a | A | A | Not available with 4 Speed in Californa or High Altitude |
| X7 | MX1 | 3-Speed Turbo Hydramatic Transmission (Turbo 350) | n/a | n/a | A | A |
| L80 | V-8 | Oldsmobile | 403 | 4.35 x 3.39 | 4 bbl | 7.9:1 | 185@3600 | 320@2000 | K | U2, U3, VA, VB | MX1 | 3-Speed Turbo Hydramatic Transmission (Turbo 350) | | | n/a | n/a | A | A | Standard on Trans Am and optional on Formula in California and High Altitude |
1978 Firebird Transmissions
| UPC Code | Type | Usage | Codes | Base | Esprit | Formula | Trans Am | Notes |
| MM3 | 3 Speed Manual Transmission | LD5 231cid V6 (Buick) | | S | S | n/a | n/a | Not availble in California or High Altitude |
| MM4 | 4 Speed Wide Ratio Manual Transmission | LG3 305 cid V8 (Chevrolet) | | n/a | n/a | S | n/a | Not available in California or High Altitude |
| LM1 350 cid V8 (Chevrolet) | n/a | n/a | A | n/a |
| M21 | 4 Speed Close Ratio Manual Transmission | W72 400 cid V8 | | n/a | n/a | A | A | |
| MX1 | 3-Speed Turbo Hydramatic Transmission (Turbo 350)* | LD5 231 cid V6 (Buick) | | A | A | n/a | n/a | |
| LG3 305 cid V8 (Chevrolet) | | A | A | A | n/a |
| LM1 350 cid V8 (Chevrolet) | | A | A | A | n/a |
| L78 400 cid V8 | | n/a | n/a | A | S |
| W72 400 cid V8 | | n/a | n/a | A | A |
| L80 403 V8 (Oldsmobile) | | n/a | n/a | A | A | California and High Altitude Only |
1970 Engines
V8 engines were painted in a light blue metallic color. 6 Cylinders were Chevrolet Orange.
The Buick sourced V-6, standard in the base and Esprit models is easily distinguished by it's small form.
The Chevrolet-sourced 305cid V-8 has a shorter air cleaner cover than the 350cid.
Chevrolet sourced engines are most easily identified in the Firebird line by having the alternator
mounted on the passender side of the engine and air conditioning unit (if so equipped) on the driver side.
This is opposite of Pontiac sourced engines.
The Chevrolet-sourced 350cid V-8 has a taller air cleaner cover than the 305cid.
Chevrolet sourced engines are most easily identified in the Firebird line by having the alternator
mounted on the passender side of the engine and air conditioning unit (if so equipped) on the driver side.
This is opposite of Pontiac sourced engines.
The Oldsmobile-sourced 403 is easily identified by the oil filler tube, sticking out of the top of the engine.
The Olds 403 is actually considered a small block.
The base 400 V-8 is basically the same block as the W-72 400 but was adorned with
blue-painted valve covers and an aircleaner with a round hose and round intake.
The W72 400 can be identified by the satin chrome valve covers and a larger, oval air hose opening to the
air cleaner.
Pontiac V-8 Engine (Typical)
Examples shown on this page consist of scanned images or reproduction artwork that can not be faithfully reproduced on a computer screen. Illustrations are for example only. Consult with your vendors offerring reproduction
parts for their historical accuracy.