Mercury 430ci Specs: 4.30 x 3.70 in

Mercury 430ci specs: 4.30 x 3.70 in (109.2 x 94 mm) bore and stroke. Displacement, compression and factory ratings for each, plus rod ratio and piston speed.

At a glance

Displacement	430 ci
Cylinders	8
Bore	4.300"
Stroke	3.700"
Compression	10.5:1
Advertised power	310–400 hp
Years	1958–1960

This engine

Engine	Displacement	Bore × Stroke	CR	HP
Mercury 430ci (1958–1960)	430 ci	4.3" × 3.7"	10.5:1	310–400

Factory cars with a Mercury 430ci

• Mercury Montclair: 1958, 400 hp; 1960, 310 hp
• Mercury Monterey: 1958, 400 hp
• Mercury Park Lane: 1958, 360 hp; 1958, 400 hp; 1959, 345 hp; 1960, 310 hp

What varies across the family

This family is represented by a single engine in the database: 430 ci, 8 cylinders, a 4.3" × 3.7" 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