Behemoth Helix IS Independent Suspension EV Gearbox – E30 / E40 Limited-Slip

The Behemoth Drivetrain Helix IS is a limited-slip differential gearbox for electric vehicles with independent suspension. The motor bolts straight to the back of it on a splined input, and half-shafts run to each wheel, so one unit replaces both the transmission and the rear end. Run it at the front or the rear.

Choose your model

• E30 (Dana 30): compact and light, for sports cars, rear-IRS Porsches and Volkswagens, restomods, buggies and other lightweight to mid-size EVs.
• E40 (Dana 44): heavy-duty, for heavier vehicles, bigger tires, off-road, commercial and motorsport use.

Both are engineered for the torque, RPM and heat of an electric motor and are self-contained like any conventional differential, with no external cooler or pump to plumb. Built and assembled in the USA.

Gearing

The Helix IS uses standard Dana ring-and-pinion sets. On the E30, common choices run from 3.73 for top speed up to 4.88 or 5.13 for launch and bigger tires. Changing ratio later is a normal diff job. Tell us your motor, tire size and target top speed and we'll recommend one.

Notes from the Current EV team

Everything we sell is a part we use in our own builds. The E30 is small and strong: it fits where bigger diffs won't and still handles serious motor torque. It works really well in rear-IRS cars like Porsches and Volkswagens, and we like that you can run it at the front too, which opens up dual-motor and all-wheel-drive builds. When the vehicle is heavier or the tires get bigger, the E40 gives you the same layout with Dana 44 strength.

Specifications

If you're keeping a solid rear axle, see the Behemoth Helix IL inline gearbox.

Typical lead time is 6–8 weeks. Ships by pallet freight, quoted separately. Contact our engineers to confirm model, fitment and ratio.