RM Racing Electronics · Universal wire-in ECU · SKU 104
Runs your engine.
Shifts your 8HP.
RM-Primis is a universal wire-in standalone ECU — 1–12 cylinders, full sequential to 6, two-channel knock control, drive-by-wire and OEM CAN. Native ZF 8HP gearbox control is built in. No second controller. No second software. $0 extra.
8HP control: $0.00
Free engineer support / Full docs portal / Ongoing firmware & software updates
The problem we removed
An 8HP swap used to need two controllers.
Engine management on one box, gearbox control on another, two wiring jobs and two programs to learn. RM-Primis collapses all of it into one ECU that already knows load, throttle, torque and RPM — and shifts the box accordingly.
The usual parts list
- Standalone engine ECU
- Separate ZF 8HP controller box
- Second wiring & power plan
- Second software to learn
- Two support queues when it plays up
The RM-Primis parts list
- One ECU — engine and gearbox on CAN
- One software — RM-Tuner for tuning, logging and 8HP diagnostics
- Original 8HP TCU retained — ZF8HP45 / ZF8HP70
- One support team — the engineers who built it
- 8HP control on the invoice: $0.00
Order sheet
Everything below ships for one price.
OPTIONS AT CHECKOUT: DRIVE-BY-WIRE SET · LSU 4.9 WIDEBAND · 3 M UNIVERSAL HARNESS
Capabilities
Spec’d for swaps, boost and track time.
These aren’t spec-sheet fillers. They’re the functions you reach for when the car is on the lift with a laptop plugged in.
Power delivery PWR
- Launch control for repeatable starts
- Rally-style antilag, external bypass valve supported
- Flat shift — torque cut for no-lift gear changes
- Boost control, open/closed-loop PID with dual tables
Engine protection PRT
- Rev limiter configurable by temp, cut type and events
- Lean cut and boost cut before things get expensive
- Overrun fuel cut adjustable by CLT, RPM, MAP
- Programmable safeties on any analog sensor — oil & fuel pressure
Knock & ignition IGN
- 2-channel knock control, per-cylinder thresholds
- Timing pull & recovery configurable per knock event
- VR and Hall crank/cam trigger support
- Sequential ignition to 6 cyl, wasted spark / batch to 12
Throttle, cam & idle CTL
- Drive-by-wire with auto-tune PID, targets and feedforward
- VVT / VANOS / VVTi closed loop, 2 solenoids per cam
- Idle control via DBW, ignition or 1/3-wire valve
- Rotary modes — sequential fuel, RX-7 wasted spark
Transmission
ZF 8HP control. Included, not sold separately.
RM-Primis talks to the original ZF 8HP TCU over CAN bus. The ECU that already runs your engine handles the gearbox — shifting, shifter, paddles and diagnostics — inside the same RM-Tuner software.
- No separate 8HP controller box to buy, mount or wire
- Original TCU & mechatronics retained — ZF8HP45 / ZF8HP70 supported
- BMW F-Series shifter support where fitted
- Paddle-shift inputs for compatible setups
- TCU flashing supported where required
- Engine + gearbox diagnostics in one software
Setup docs: 8HP CAN transmission · 8HP paddles
Software
RM-Tuner is free. The updates don’t stop.
Tuning, real-time datalogging, output configuration and diagnostics in one program — included with every ECU, no licence tiers. Firmware and software are updated constantly, and new functions are regularly added from customer requests. Wideband input for Bosch LSU 4.9 / 4.2 gives you closed-loop fueling from day one.
Process
Order to first start, three moves.
Spec it
Pick your throttle set, wideband and harness at checkout. Not sure? Send your engine details and we’ll confirm the right configuration before you pay.
Wire it
Connector and terminals ship with every ECU; the 3 m universal harness saves hours on custom installs. Wiring references live in the docs portal, and engineer email support is free.
Start it
Verify sensors and triggers live in RM-Tuner, fire it up, then tune fuel, ignition, boost and protections. Running an 8HP? The gearbox comes alive in the same session.
Configuration
Spec your ECU before you hit buy.
Three choices on the product page. Here’s how to get them right first time.
With or without drive-by-wire
Electronic throttle body on the engine? Take the DBW set — auto-tune PID makes setup quick. Cable throttle? Order without and save the difference.
LSU 4.9 sensor
Add the Bosch LSU 4.9 for closed-loop fueling and safer tuning — the right call on any turbo build. Already own a compatible sensor? Skip it, the controller input is onboard.
3 m universal harness or ECU only
The 3 m harness is the fast route for swaps. Building your own loom? ECU only still includes the connector and terminals.
Datasheet
RM-Primis, line by line.
| Parameter | Specification |
|---|---|
| Engine support | 1–12 cylinders. Full sequential fuel & ignition to 6 cyl; wasted spark or batch fire to 12. Rotary supported — currently up to 2 rotors, sequential fuel, RX-7 wasted spark modes. |
| Triggers | VR and Hall crank / cam sensors. |
| Onboard sensor | 400 kPa MAP sensor built into every ECU. |
| Inputs | 8 general-purpose analog inputs (0–5 V / thermistor) with programmable calibration, plus dedicated IAT, CLT and TPS channels. |
| Outputs | 6 low-side + 4 high-side outputs (5/12 V). Spare injector channels usable as extra outputs. PWM fan control. |
| Throttle & idle | Drive-by-wire with auto-tune PID, target tables, feedforward. Idle via DBW, ignition control or 1/3-wire valve, open/closed loop. |
| Cam control | VVT / VANOS / VVTi, open/closed loop, up to 2 solenoids per cam. |
| Boost & knock | Dual-table PID boost control. 2-channel knock with per-cylinder thresholds, timing adjustment and recovery per event. |
| Wideband | Onboard controller input for Bosch LSU 4.9 or LSU 4.2. |
| CAN bus | Full vehicle integration, multiple OEM CAN protocols, transmissions and advanced implementations. |
| Transmission | Native ZF 8HP control over CAN with the original TCU — included at no extra cost. ZF8HP45 / ZF8HP70, BMW F-Series shifter, paddle inputs, TCU flashing where required. |
| Software | RM-Tuner tuning & real-time datalogging, included with free ongoing updates. |
| In the box | ECU with female connector and terminals. Options: 3 m universal harness, LSU 4.9 wideband sensor, drive-by-wire set. |
Before you ask
Straight answers.
Will it run my engine?
Almost certainly: 1 to 12 cylinders, full sequential to 6, wasted spark or batch fire to 12, rotary engines up to 2 rotors, VR or Hall triggers, cable or electronic throttle. Send us your engine code and setup and we’ll confirm before you order.
Is the ZF 8HP control actually free?
Yes. 8HP CAN control is built into every RM-Primis at no extra cost — the original TCU and mechatronics stay in the car. You only add the transmission wiring parts your install needs, like the 8HP harness or timed relay. TCU flashing is supported where required.
Do I pay for the software?
No. RM-Tuner tuning and datalogging software is included, with no licence tiers. Firmware and software updates are free and ongoing — many new features come straight from customer requests.
What comes in the box?
The ECU with its female connector and terminals, ready for wiring. Depending on the options you choose: the 3 m universal harness, the Bosch LSU 4.9 wideband sensor and the drive-by-wire set.
Can I install it myself?
Many customers do. The documentation portal covers wiring, setup and configuration step by step, and email support from our engineers is free. For final power tuning, verify properly — on a dyno where possible.
What protects the engine while tuning?
A configurable rev limiter, lean cut, boost cut, overrun fuel cut, two-channel knock control with per-cylinder thresholds, and programmable safeties on any analog sensor — oil pressure and fuel pressure included.
RM-Primis · SKU 104
Engine and gearbox. One box.
From $780.
Sequential engine management, knock control, drive-by-wire, OEM CAN, RM-Tuner software and native ZF 8HP control — on one invoice. Configure yours, or send us the build and we’ll spec it with you.
Manufacturer-direct / docs.rmracingelectronics.com / Free engineer support