BMW GS7 7-Speed Short Ratio (E-Chassis) gear ratios
The BMW GS7 7-Speed Short Ratio (E-Chassis) is a seven-speed dual-clutch gearbox.
First gear is 4.78:1 and 7th is 1.00:1. Divide one by the other and the overall spread is 4.78:1. That is a wide spread: a short first to get the car moving and a tall top to bring cruise revs down.
Top gear is direct drive at 1.00:1, so there is no overdrive. Cruise revs are down to the final drive alone.
The biggest step is 1st to 2nd, where the ratio drops 39%. The smallest is 5th to 6th at 13%. On each upshift the revs drop by the same percentage as the ratio.
The final drive lives in a separate diff, so the speed table shows three common ratios: 3.42, 3.73 and 4.10. With a 3.73 final drive and 225/45R17 tyres, 7th at 6,000 rpm works out at 192 km/h (120 mph), and first runs out at 40 km/h (25 mph). At 70 mph in 7th the engine turns about 3,510 rpm.
Ratios
BMW GS7 7-Speed Short Ratio (E-Chassis): ratio per gear, and how far the ratio drops from the gear before.
Gear
Ratio
Step
1st
4.78:1
-
2nd
2.933:1
38.6%
3rd
2.153:1
26.6%
4th
1.678:1
22.1%
5th
1.39:1
17.2%
6th
1.203:1
13.5%
7th
1.00:1
16.9%
Road speed at 6,000 rpm
Road speed at 6,000 rpm on a 225/45R17 tyre (1.993 m rolling circumference), by final drive. No slip, no drivetrain losses.
Results are theoretical: stock ratio specs, your inputs, no drivetrain losses. Verify with your drivetrain supplier before spending real money.
Swapping the engine as well? StandaloneHQ counts the inputs and outputs the new engine needs and shortlists the wire-in ECUs that fit: ECU Pinout Planner.
BoxSelector crunches gear ratios, tyre sizes, and RPM figures to give you useful speed and cruise data for your build. The results are theoretical, based on stock ratio specs and your inputs, and assume perfect mechanical conditions, zero drivetrain losses, and a world without speed bumps, traction limits, or your right foot getting sweaty. Real-world results will vary. Probably a lot for automatics.
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Gear ratios may have changed, and manufacturers love to quietly update things.
We've done our best to source accurate ratio data from factory specs and reputable technical references. Some ratios (particularly on production variants with running changes) may differ from the figures listed here. Always verify critical specs against your actual unit or a current manufacturer source before committing to anything expensive.
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