Oldsmobile LT7 Specs: 4.057 x 3.385 in, 85 hp

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Oldsmobile LT7 specs: 262 ci (4.3L) 6-cylinder, 4.057 x 3.385 in (103 x 86 mm) bore and stroke. Rated 85 hp, 1982–1985. Used in the Oldsmobile Cutlass. OHV.

The Oldsmobile 262ci (LT7) is oversquare — the 4.057" bore exceeds the 3.385" stroke by 19.9% — a layout that favors airflow and RPM over leverage at the crank. The 3.385" stroke does not reach 4,000 ft/min of mean piston speed until about 7,100 RPM, so piston speed is not what limits this engine's revs — valvetrain and breathing are. A rod ratio of 1.739 is in the range most production engines fall in. Each of the 6 cylinders displaces 43.7 ci (716 cc).

It is one of 2 engines in the Oldsmobile 262ci family, all of them 262 ci — the differences between them are in compression, heads and rating, not displacement. 3 factory variants share these dimensions, rated at 85 hp across 1982–1985.

Dimensions

Displacement262 ci / 4.3 L
Bore4.057"
Stroke3.385"
Cylinders6
ConfigurationV6
Rod length5.885"
Rod ratio1.739
Bore/stroke ratio1.199

Construction

Block materialcast iron
Head materialcast iron
ValvetrainOHV
Fuel typediesel
Advertised HP85 hp
Years1982–1985

What these numbers mean

Bore/stroke character1.199 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves
Mean piston speed at 6,000 RPM3,385 ft/min — conservative for a street engine
Rod ratio1.739 — moderate — the range most production V8s fall in
Displacement per cylinder43.7 ci

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Variants sharing these dimensions (3)

These records share identical bore, stroke, displacement and compression. They differ by model year and factory power rating.

YearAdvertised HPCode
198285 hpLT7
198385 hpLT7
198585 hpLT7

Factory cars with this engine

Similar engines

← All Oldsmobile 262ci engines