Acura B20A Specs: 81 x 95 mm (3.1890 x 3.7402 in)

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The same engine also has a main page: Honda B20A5.

Acura B20A specs: 2.0L (119.5 ci) 4-cylinder, 81 x 95 mm (3.1890 x 3.7402 in) bore and stroke. Used in the Honda Prelude. Rod ratio and piston speed.

The Acura B20A is undersquare — the 3.7402" stroke exceeds the 3.189" bore by 14.7% — a layout that trades peak RPM for leverage and torque low in the range. The 3.7402" stroke puts mean piston speed at 4,000 ft/min around 6,400 RPM, which is where a production bottom end is generally considered at its limit. Each of the 4 cylinders displaces 29.9 ci (490 cc).

It is one of 15 engines in the Honda B-series family, sitting between the 97 ci and 121.8 ci members.

Dimensions

Displacement119.5 ci / 2 L
Bore3.189"
Stroke3.7402"
Cylinders4
Bore/stroke ratio0.853

Construction

Fuel typegas
Firing order1-3-4-2

What these numbers mean

Bore/stroke character0.853 — undersquare — stroke exceeds bore, which favours low-end torque
Mean piston speed at 6,000 RPM3,740 ft/min — in the range typical of performance street engines
Displacement per cylinder29.9 ci

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What cars have the B20A?

1 factory vehicle, 1988–1991. Each year opens that model's engine table.

Similar engines

← All Honda B-series engines