Chevrolet 400ci Specs: 4.125 x 3.75 in

Chevrolet 400ci specs: 4.125 x 3.75 in (104.8 x 95.3 mm) bore and stroke, shared by all 7 versions. Displacement, compression and factory ratings.

At a glance

Displacement	400 ci
Cylinders	8
Bore	4.125"
Stroke	3.750"
Compression	9.0–10.2:1
Advertised power	150–265 hp
Years	1970–1979
Cylinder head data	3 of 7 engines

Engines in this family

Engine	Displacement	Bore × Stroke	CR	HP
Chevrolet 400ci · 4.125" × 3.750" · 9.201:1	400 ci	4.125" × 3.75"	9.201:1	170–255
Chevrolet 400ci (1973) · 150 hp	400 ci	4.125" × 3.75"	9.031:1	150
Chevrolet 400ci · 4.125" × 3.750" · 10.201:1	400 ci	4.125" × 3.75"	10.201:1	175–180
LF6	400 ci	4.125" × 3.75"	—	150–265
Chevrolet 400ci (1976–1978)	400 ci	4.125" × 3.75"	—	175
LF4	400 ci	4.125" × 3.75"	—	175–185
LT4	400 ci	4.125" × 3.75"	—	175

Factory cars with a Chevrolet 400ci

• Chevrolet Bel Air: 1970, LF6, 265 hp
• Chevrolet Caprice: 1970, LF6, 265 hp; 1971, LF6, 255 hp; 1972, LF6, 170 hp; 1973, LF6, 150 hp; 1974, LF6, 150 hp; 1974, LT4, 180 hp; 1975, LT4, 175 hp; 1976, LT4, 175 hp
• Chevrolet Impala: 1970, LF6, 265 hp; 1971, LF6, 255 hp; 1972, LF6, 170 hp; 1973, LF6, 150 hp; 1974, LF6, 150 hp; 1974, LT4, 180 hp; 1975, LT4, 175 hp; 1976, LT4, 175 hp
• Chevrolet Monte Carlo: 1970, LF6, 265 hp; 1974, LF6, 150 hp; 1974, LT4, 180 hp; 1975, LT4, 175 hp; 1976, LT4, 175 hp
• Chevrolet Chevelle: 1974, LF6, 150 hp; 1974, LT4, 180 hp; 1975, LT4, 175 hp; 1976, LT4, 175 hp
• Chevrolet El Camino: 1974, LF6, 150 hp; 1974, LT4, 180 hp; 1975, LT4, 175 hp; 1976, LT4, 175 hp
• Chevrolet C/K Pickup: 1975, 175 hp; 1976, 175 hp; 1977, 175 hp; 1978, 175 hp; 1979, LF4, 185 hp
• Chevrolet K5 Blazer: 1975, LF4, 175 hp; 1976, LF4, 175 hp; 1977, LF4, 175 hp; 1978, LF4; 1979, LF4, 185 hp
• Chevrolet Suburban: 1975, 175 hp; 1976, 175 hp; 1977, 175 hp; 1978, 175 hp; 1979, LF4, 185 hp
• GMC Jimmy: 1975, LF4, 175 hp; 1977, LF4, 175 hp; 1978, LF4, 175 hp; 1979, LF4, 185 hp

What varies across the family

All are oversquare — bore larger than stroke, which favours revs over low-end torque.

Each engine page carries rod ratio, mean piston speed, bore/stroke character and cylinder head specs where published, and links into the calculators with its dimensions already filled in.

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