The ZF 8HP70-behind-an-LS idea circulated in the swap community for years before anyone could buy the parts for it. That era is over — there are now two billet adapter kits on the shelf, one for Mopar/Ram donors and one for Jaguar/Land Rover donors. What's left are the mistakes builders keep making anyway: buying the wrong donor transmission, ordering a driveshaft before sorting gearing, and treating the flexplate as a leftover part.
Why the LS-to-8HP Combination Is Popular
LS engines are everywhere, cheap, and famously easy to build power into. The 8HP70 is rated to handle 700 Nm from the factory and, like other 8HP variants, is known to take considerably more than that in practice. Pairing the two gives you an engine platform with essentially unlimited aftermarket support behind a transmission that shifts in under 100 milliseconds and offers an 8-speed gear spread most GM automatics can't match.
The Adapter: No Longer a Fabrication Project
For a long time this swap was developed by individual builders and small shops rather than standardized by a kit manufacturer. Documented builds — including a widely discussed 1966 Fairlane project pairing a Holley Dominator ECU with a TurboLamik TCU over CAN — proved the combination worked, but the mechanical interface was one-off work: a plate machined to order, or a CD009-pattern LS adapter modified on the transmission side.
We machine that piece now, in two versions. Not every 8HP has the same bellhousing or torque converter, so the kit you need is set by where your transmission came from. Both adapt to any Gen 3, Gen 4 or Gen 5 LS or LT, and both include a billet flex plate that fully replaces the stamped OEM unit — the part builders most often got wrong when doing it themselves.
Mopar or Jaguar: Which Kit Fits Your Donor
The two kits are not interchangeable. Pick the donor first, then the kit that matches it.
| Mopar / Ram kit | Jaguar / Land Rover kit | |
|---|---|---|
| Transmissions | 8HP70, 8HP75, 8HP90, 8HP95 | 8HP45 and 8HP70 |
| Donor vehicles | Ram 1500 (2012–2024), Ram TRX, Charger, Challenger, 300, Durango, Grand Cherokee HEMI (2015–2023) | Jaguar F-Type, XF, XJ (2013–2020), Range Rover Sport V6/V8 (2014–2019) |
| Converter pilot | Press-fit steel pilot adapter included (46mm and 34mm) | Single-diameter pilot — no adapter needed |
| Starter clearance | Truck units have the pocket; car units need the bellhousing trimmed | Bellhousing needs clearancing for the stock LS starter |
| Other notes | Driver-side starter boss may need relief for header clearance | No converter bolt access window to cut |
| Price | $1,299.99 | $1,299.99 |
Donor Transmission: What Each Family Gets You
Mopar and Ram
The 2015+ Charger, Challenger and 300 8HP70 is the cheap, abundant pick. But car-platform 8HP units have no passenger-side starter provision cast into the bellhousing, so they need trimming to clear the LS/LT starter snout. Truck-spec units from the Ram side already have the pocket. If you'd rather not cut a bellhousing, buy a truck transmission — and if you want more headroom, the Ram TRX 8HP95 brings a higher factory torque rating in the same architecture.
Jaguar and Land Rover
Jaguar and Range Rover Sport units are worth a look if one turns up at the right price, and the install is simpler in two ways: no pilot adapter, and no converter bolt access window to cut. The bellhousing still needs clearancing for the factory LS starter, which then bolts up unmodified. Know which unit you're getting, though — the 8HP45 from the X250 XF and XJ is the lighter-duty transmission, rated around 450 Nm, and belongs behind a near-stock engine. For a built LS or LT, look for an 8HP70 from the F-Type, XF, XJ or Range Rover Sport.
Engine Fitment Is the Same for Both Kits
- Gen 3 LS — 4.8L, 5.3L, 6.0L. Does not fit early long-crank 5.3L and 6.0L engines.
- Gen 4 LS — 4.8L, 5.3L, 6.0L, 6.2L, 7.0L. 8-bolt and 9-bolt crankshaft variants by special order.
- Gen 5 LT — all variants.
- Gen 5 90° V6 — LV1 and LV3 4.3L direct injected.
Check your crank before you order. The early long-crank Gen 3 engines are the one fitment that catches people out.
The Flexplate Is Not a Leftover Part
Don't plan on reusing a factory GM flexplate designed around a 4L60E/4L80E-style converter bolt pattern — the 8HP converter has different mounting geometry entirely. Be equally wary of the spacer approach, where a plate sandwiches against the stock stamped flexplate to reach the ZF converter. That leaves the weakest component in the driveline in service on a swap that's usually making more torque than the plate ever saw stock. A full billet replacement is the right answer; both of our kits ship with one, carrying a new hardened steel starter ring gear.
A Standalone TCU
Non-negotiable on any LS-to-8HP build, whichever donor you pick — the 8HP is electronically controlled and won't shift without one. It's also the most mature part of the whole swap. TurboLamik lists explicit compatibility for GM LS-based ECUs (E37/E38), and builders running Holley EFI have already done the CAN integration work — the Fairlane project above used exactly this combination.
A Driveshaft Solution
The 8HP70's output shaft is rated to 8,500 RPM, which matters more than it sounds — with a 3.26 differential gear and 26" tires that's roughly 200 mph before you hit the shaft speed limit; with a steeper 4.10 gear the ceiling drops to around 160 mph. Know your gearing before you finalize driveshaft length and U-joint spec. Both kit pages offer a matching driveshaft adapter as an add-on, so the transmission-side flange is covered when you order.
Rounding Out the Build
Each conversion kit is the mechanical package — adapter plate with integrated dust shield, flex plate and hardware, plus the converter pilot adapter on the Mopar kit. Flywheel bolts are standard-length OEM GM or ARP manual transmission bolts, six or eight depending on your crank, and aren't included; use ARP on anything making real power. The adapter plate takes all seven fasteners with a factory GM cast oil pan, or five with a fabricated steel pan. The transmission, converter, controller and mount are sourced separately.
If your donor is a used unit, change the fluid and filter before it goes in the car — budget for a ZF service kit alongside the adapter. A billet pan is the one upgrade worth adding on almost any 8HP swap: more cooling capacity and real protection for the mechatronics unit against road debris.
The hard part of this swap moved. It used to be the adapter plate; now it's picking the right donor — Mopar or Jaguar, truck or car, 8HP45 or 8HP70 — before you spend money on the wrong one.
If you're planning this build and want to talk through your engine and chassis combination before you buy a donor transmission, reach out — we'd rather help you avoid the wrong 8HP variant than sell you parts for a mismatch.