Engine Displacement

If you’re looking to up your engine size then this handy calculator will determine your engine displacement depending on the stroke of crankshaft and the bore of the barrels and pistons.

Engine total displacement is calculated by this calculation:

Bore x Bore x Stroke x 0.0031416



Aircooled VW Engine Displacement Barrels and Pistons

The bore of the engine is the size of the pistons. The larger the diameter the piston the more cubic capacity (cc’s) it has. A 1300cc to 1600cc crankcase can fit up to an 87mm Piston without the need for any machining. Any larger than this will require your crankcase to be machined.

Standard Piston Sizes

1200cc – 77mm

1300cc – 77mm

1500cc – 83mm

1600cc – 85.5mm


Aircooled VW Engine Displacement Crankshaft

The measurement of the centre of the crankshaft to the centre of the connecting rod is called the ‘throw’. Multiply this number by two and it will give you the stroke of the engine.

A 1200cc engine uses a 64mm stroke crankshaft. All other Type 1 engine sizes use a 69mm stroke crankshaft as standard.

Longer stroke crankshafts are used to increase the engine displacement. When the stroke is longer, more torque is developed at lower RPM but the issue with larger strokes is a reduction in top end RPM. Maximum stroke in an Aircooled VW crankcase is 84mm (any larger would not fit in the case) this does not cause an issue. So the larger the stroke the better!

Hopefully this information has helped you to calculate your engine displacement. If however you are still unsure then please do not hesitate to contact us.  You can email us at sales@coolairvw.co.uk, Facebook Message us or call our shop on 01322 335050