1975 Firebird Engines

RPO Code	UPC Code	Type	Source	Displ cid	Bore & Stroke	Carb	Comp	HP/RPM Net	Torque/RPM	VIN	Engine Block code(s)	Trans RPO	UPC	Transmission	Axle	Opt Axle	Base	Esprit	Formula	Trans Am	Notes
36D	L22	Inline 6	Chevrolet	250	3.875 x 3.531	1 bbl	8.25:1	105@3800	185@1200	D	JL, JT, JU	37B	M15	3 Speed Manual (Floor Shift)	2.73:1		S	n/a	n/a	n/a
36D	L22	Inline 6	Chevrolet	250	3.875 x 3.531	1 bbl	8.25:1	105@3800	185@1200	D	JL, JT, JU	37L	M38	3-Speed Turbo Hydramatic Transmission (Turbo 350)	2.73:1		A	S	n/a	n/a
36M	L30	V-8	Pontiac	350	3.875 x 3.75	2 bbl	7.6:1	155@4000	280@2000	M	YB	37L	M38	3-Speed Turbo Hydramatic Transmission (Turbo 350)	2.56:1		A	A	n/a	n/a
36E	L76	V-8	Pontiac	350	3.875 x 3.75	4 bbl	7.6:1	175@4000	280@2000	H	YN, YO	37E	M20	4 Speed Wide Ratio Manual Transmission	3.08:1		A	A	S	n/a
36E	L76	V-8	Pontiac	350	3.875 x 3.75	4 bbl	7.6:1	175@4000	280@2000	H	ZP	37L	M38	3-Speed Turbo Hydramatic Transmission (Turbo 350)	2.56:1		A	A	A	n/a
36S	L78	V-8	Pontiac	400	4.125 x 3.75	4 bbl	7.6:1	185@3600	310@1600	R or S	WT	37E	M20	4 Speed Wide Ratio Manual Transmission	3.08:1		n/a	n/a	A	S
											WT	37F	M21	4 Speed Close Ratio Manual Transmission	3.08:1		n/a	n/a	A	A	No cost option in Formula and Trans Am
											YS	37L	M38	3-Speed Turbo Hydramatic Transmission (Turbo 350)	2.56:1		n/a	n/a	A	A
36W	L75	V-8	Pontiac	455 HO	4.15 x 4.21	4 bbl	7.6:1	200@3500	330@2000	W	WX	37E	M20	4 Speed Wide Ratio Manual Transmission	3.08:1		n/a	n/a	n/a	A	The 455 HO was introduced mid-year
36W	L75	V-8	Pontiac	455 HO	4.15 x 4.21	4 bbl	7.6:1	200@3500	330@2000	W	WX	37F	M21	4 Speed Close Ratio Manual Transmission	3.08:1		n/a	n/a	n/a	A	The 455 HO was introduced mid-year

1975 Firebird Transmissions

RPO Code	UPC Code	Type	Usage	Codes	Base	Esprit	Formula	Trans Am	Notes
37B	M15	3 Speed Manual Transmission, Floor Mounted	L22 250 cid Inline 6 Cylinder		S	n/a	n/a	n/a
37E	M20	4 Speed Wide Ratio Manual Transmission (Floor Shift)	L76 350 cid V8		A	A	S	n/a
			L78 400 cid V8 4bbl		n/a	n/a	A	S
			L75 455 HO		n/a	n/a	n/a	A
37F	M21	4 Speed Close Ratio Manual Transmission (Floor Shift)	L78 400 cid V8 4bbl		n/a	n/a	A	A	No cost upgrade to Formula and Trans Am
37F	M21	4 Speed Close Ratio Manual Transmission (Floor Shift)	L75 455 HO		n/a	n/a	n/a	A	No cost upgrade to Formula and Trans Am
37L	M38	3-Speed Turbo Hydramatic Transmission (Turbo 350)	L22 250 cid Inline 6 Cylinder		A	S	n/a	n/a
			L30 350 cid V8		A	A	n/a	n/a
			L76 350 cid V8		A	A	A	n/a
			L78 400 cid V8 4bbl		n/a	n/a	A	A

1975 Engines

Where to find the Engine ID stamping

Chevrolet made Inline 6 Cylinder Engine (Typical)

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.