Mercury 383ci Specs: 4.30 x 3.30 in

Mercury 383ci specs: 4.30 x 3.30 in (109.2 x 83.8 mm) bore and stroke. Displacement, compression and factory ratings, plus rod ratio.

At a glance

Displacement	383 ci
Cylinders	8
Bore	4.300"
Stroke	3.300"
Compression	10.5:1
Advertised power	280–330 hp
Years	1958–1960

This engine

Engine	Displacement	Bore × Stroke	CR	HP
Mercury 383ci (1958–1960)	383 ci	4.3" × 3.3"	10.5:1	280–330

Factory cars with a Mercury 383ci

• Mercury Montclair: 1958, 330 hp; 1959, 322 hp
• Mercury Monterey: 1958, 312 hp; 1959, 280 hp; 1960, 280 hp

What varies across the family

This family is represented by a single engine in the database: 383 ci, 8 cylinders, a 4.3" × 3.3" bore and stroke.

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.

← All Mercury engines