8HP Conversions

The ZF 8HP is the most popular swap transmission on the market — sub-100-millisecond shifts, an 8-speed spread that keeps any engine in its power band, and enough factory production volume (15M+ units across 20+ brands) to keep donor transmissions cheap and easy to find. This collection covers the complete conversion: adapter kits, driveshaft adapters, transmission control, and the hardware upgrades that separate a swap that lasts from one that doesn't.

Start Here: The Full Range Explained

A walkthrough of every kit on the bench — which transmission variants are covered, which engines, and what is actually in the box. Read the written version →

Choosing Your 8HP Variant

All three variants handle meaningfully more than their factory rating in practice. For most builds, the 2015+ Dodge Charger/Challenger/300-sourced 8HP70 is the practical sweet spot — abundant, inexpensive, and backed by the widest adapter and controller support of any 8HP variant.

Why the BMW units cost more

BMW 8HPs mostly turn up in diesels, Mk5 Supras and newer BMWs running B58 and S58 engines. They are pricier, but they carry a noticeably smaller bell housing case — which is worth paying for when transmission tunnel clearance is the constraint.

The reason the cheaper Dodge and Jaguar units became viable at all is TCU support. As standalone controllers started covering more variants, the more plentiful transmissions opened up. That is why this range exists.

What Every ASE Kit Includes

• Billet flex plate with a brand new starter ring gear. Full solid pieces, everything integrated — factory flex plates are not reused where it can be avoided. On JZ applications this matters most: the factory plates are old and prone to cracking, and street car power has roughly doubled over the last several years.
• Stainless hex-drive dowel pins. Threaded rather than pressed, so they screw in and seat without risk of bending. Replaceable if damaged. Both common sizes use an 8mm hex drive. (BMW kits still use factory dowels.)
• Converter centering hardware. Adapter sleeves and alignment spuds let a single plate cover multiple converter diameters — on the Dodge kits, both second and third generation converter spuds. Retention lips and relief points mean a seized sleeve taps straight back out.
• Engraved torque specifications laser or machine cut directly into the face of most current flex plates and adapter plates.
• In-house 6061 billet machining in deliberately small batches, so revisions roll in between runs and a tooling issue costs one or two parts rather than fifty.

Don't See Your Engine?

If a combination is not listed, it has not come up the priority list yet — it is not a refusal.

The real constraint is access to an engine. A live engine on site is preferred for final fitment and for filming the install guide, but what is strictly required is a very high quality 3D scan of the crank side of the engine. Rolled edges and poorly defined transmission and crank holes are not usable — the ASE scanner resolves to roughly two microns, and that edge definition is what produces the fit on the finished plate.

Every transmission ASE has already adapted has been scanned: all the Dodge 45s, the 70 and 90 series, most of the BMWs including the V8 units, and the Jaguars. A good engine scan plus a transmission already covered can move quickly. Get in touch.

Coyote and VK kits are in development — both engines are on the stand and already scanned.

Not sure which kit fits your engine and donor transmission combination? Reach out before you buy — matching the right adapter, 8HP variant, and controller up front is a lot cheaper than discovering a mismatch mid-install.