Pontiac V8 engine

Pontiac V8 engine
Overview
ManufacturerPontiac (General Motors)
Also calledStrato Streak
Production1955–1981 Pontiac Assembly
(engine block and heads)
Saginaw Metal Casting Operations
Layout
Configuration90° V8
Displacement265 cu in (4.3 L)
287 cu in (4.7 L)
301 cu in (4.9 L)
303 cu in (5.0 L)
317 cu in (5.2 L)
326 cu in (5.3 L)
347 cu in (5.7 L)
350 cu in (5.7 L)
370 cu in (6.1 L)
389 cu in (6.4 L)
400 cu in (6.6 L)
421 cu in (6.9 L)
428 cu in (7.0 L)
455 cu in (7.5 L)
Cylinder bore3.72 in (94.5 mm)
3+34 in (95.3 mm)
3.78 in (96 mm)
3+78 in (98.4 mm)
3.9375 in (100.01 mm)
4 in (101.6 mm)
4+116 in (103.2 mm)
4+332 in (104 mm)
4.121 in (104.7 mm)
4.1525 in (105.47 mm)
4.342 in (110.3 mm)
Piston stroke2.84 in (72.1 mm)
3 in (76.2 mm)
3+14 in (82.6 mm)
3.5625 in (90.49 mm)
Cylinder block materialCast iron
Cylinder head materialCast iron
ValvetrainOHV 2 valves per cyl.
Compression ratio7.9:1, 8.0:1, 8.4:1, 8.5:1, 8.6:1, 8.9:1, 10.0:1, 10.25:1, 10.5:1, 10.75:1, 11.0:1
RPM range
Max. engine speedvaries
Combustion
TurbochargerGarrett TBO-305 (in 301)
Fuel systemRochester or Carter carburetors
Fuel injection
Fuel typeGasoline
Cooling systemWater-cooled
Output
Power output120–310 hp (89–231 kW) SAE (370 bhp)
Torque output245–500 lb⋅ft (332–678 N⋅m)
Dimensions
Dry weight550 to 650 lb (250 to 290 kg)[citation needed]

The Pontiac V8 engine is a family of overhead valve 90° V8 engines manufactured by the Pontiac Division of General Motors Corporation between 1955 and 1981. The engines feature a cast-iron block and head and two valves per cylinder. Engine block and cylinder heads were cast at Saginaw Metal Casting Operations then assembled at Tonawanda Engine before delivery to Pontiac Assembly for installation.

Initially marketed as a 287 cu in (4.7 L), it went on to be manufactured in displacements between 265 cu in (4.3 L) and 455 cu in (7.5 L) in carbureted, fuel injected, and turbocharged versions. In the 1960s the popular 389 cu in (6.4 L) version, which had helped establish the Pontiac GTO as a premier muscle car, was cut in half to produce an unusual, high-torque inline four economy engine, the Trophy 4.

Unusual for a major automaker, Pontiac did not have the customary "small-block" and "big-block" engine families common to other GM divisions, Ford, and Chrysler. Effectively, production Pontiac V8 blocks were externally the same size (326-455) sharing the same connecting rod length 6.625 in (168.3 mm) and journal size of 2.249" (except for the later short deck 301 and 265 produced in the late 1970s and early 1980s before Pontiac adopted universal GM engines). The crankshaft stroke and main journal size changed among the years with the more popular 389CI and 400CI having a 3.00" diameter main journal and the 421/428/455 sharing a larger 3.25" diameter main journal.

The V8 was phased out in 1981, replaced by GM "corporate engines" such as the Chevrolet 305 cu in small block V8.