BMW S68B44 Specs: 89 x 88.3 mm (3.5039 x 3.4764 in), 617-717 hp

See other engines in this family

BMW S68B44 specs: 4.4L (268 ci) 8-cylinder, 89 x 88.3 mm (3.5039 x 3.4764 in) bore and stroke, 10.5:1 compression. Rated 617-717 hp, 2023–2026.

The BMW S68B44 is close to square: 3.5039" bore against 3.4764" stroke, within 0.8%, which splits the difference between a high-revving layout and a torque layout. The 3.4764" stroke puts mean piston speed at 4,000 ft/min around 6,900 RPM, which is where a production bottom end is generally considered at its limit. Each of the 8 cylinders displaces 33.5 ci (549 cc).

10.5:1 is in the range that usually runs on pump premium.

It is one of 12 engines in the BMW 268ci family, all of them 268 ci — the differences between them are in compression, heads and rating, not displacement. 9 factory variants share these dimensions, rated from 617 to 717 hp across 2023–2026.

Dimensions

Displacement268 ci / 4.4 L
Bore3.5039"
Stroke3.4764"
Cylinders8
ConfigurationV8
Compression ratio10.5:1
Bore/stroke ratio1.008

Construction

Fuel typegas
Advertised HP617–717 hp
Years2023–2026

Factory ratings by year

YearVersionHP @ rpmTorque @ rpmComp.
2024S68B44 net617 @ 6000553 lb-ft @ 180010.5:1
2025S68B44 net617 @ 6000553 lb-ft @ 180010.5:1
2026S68B44 net617 @ 6000553 lb-ft @ 180010.5:1

Factory specification sheet.

What these numbers mean

Bore/stroke character1.008 — square — bore and stroke are within 5%, a balanced compromise
Mean piston speed at 6,000 RPM3,476 ft/min — conservative for a street engine
Displacement per cylinder33.5 ci
Static compression10.5:1 — in the range that usually runs on pump premium

Run the numbers for this engine

Each link opens the calculator with this engine's specs already filled in.

Variants sharing these dimensions (9)

These records share identical bore, stroke, displacement and compression. They differ by model year and factory power rating.

YearAdvertised HPCode
2023—S68B44
2024—S68B44
2024617 hpS68B44
2025—S68B44
2025617 hpS68B44
2025717 hpS68B44
2026—S68B44
2026617 hpS68B44
2026717 hpS68B44

What cars have the S68B44?

3 factory vehicles, 2023–2026. Each year opens that model's engine table.

Similar engines

← All BMW 268ci engines