About this guide

The Regal Rover Classics Rover V8 EFI kit brings Haltech Nexus R3 engine management, a purpose-built engine harness and modern sensors and ignition components to your Rover V8.

Owners can complete the mechanical installation and wiring by following this guide and the supplied EFI harness pinout. We strongly recommend workshop installation, or workshop inspection of owner-completed work before ECU setup and the first start. ECU setup and tuning must be completed by an experienced Haltech specialist familiar with Nexus R3 and NSP. Use this guide with the crank-trigger guide, current Haltech documentation and the correct factory workshop manual. Vehicle specifications and previous modifications vary.

The crank-trigger kit must be mechanically installed before the EFI installation is commissioned.

Before you begin

• Read this entire guide and the crank-trigger guide before dismantling the vehicle.
• Confirm the kit contents and the vehicle configuration.
• Save or photograph the existing installation and wire routing.
• Obtain the correct factory workshop manual and verify all relevant torque values.
• Disconnect the battery negative terminal, followed by the positive terminal.
• Relieve fuel-system pressure using the workshop-manual procedure.
• Work in a ventilated area away from sparks, flames and hot surfaces.
• Label every retained vehicle wire and connector before cutting or disconnecting it.
• Never rely on wire colour alone. Continuity-test every retained circuit against the EFI harness pinout.

Remove the factory system

First complete the wire-identification and retention step in “Before you begin”. Keep the labelled ignition, A/C and purge wires in the vehicle at the original ECU location.

Remove only the redundant engine-management loom from the engine bay back to the ECU, where fitted. Remove the old ECU and the redundant components being replaced by your kit, such as the airflow meter, distributor, ignition coil, injectors, idle-control components and engine-management sensors. The exact removal work depends on your current engine setup. Retain the starter, alternator and body circuits.

The starter, alternator, charging system, body wiring and other non-engine-management circuits remain with the vehicle. Take care not to cut or remove them.

Where the original engine loom shares routing with retained vehicle wiring, unwrap it only as far as necessary to separate the engine-management wiring from the retained vehicle wiring. Carefully cut the factory firewall grommet only as much as required to release the original harness. Clean the grommet thoroughly and retain it for installation on the new harness. Feed the original engine harness back through the firewall and remove it from the engine bay.

Fit the new components

4.1 Fuel Injectors

Remove the original injectors. Lightly lubricate the supplied Bosch injector O-rings with clean engine oil. Install the injectors into the rail and manifold, confirm that every O-ring is fully seated, and tighten the rail using the factory procedure. Do not energise the fuel pump until all fuel connections have been checked.

4.2 Intake-Air Temperature Sensor Housing

Remove the original MAF and install the supplied Regal Rover Classics MAF-replacement intake tube in the factory location using the original hose connections and clamps. The intake-air-temperature sensor is supplied already fitted to the tube. Connect the labelled IAT harness connector after the harness has been routed. A threaded boss is provided for the breather-hose connection. Drive-by-wire customers are supplied with a 90-degree fitting for this port because the original connection on the intake plenum is no longer used.

4.3 Throttle-Position Sensor (TPS) · Cable throttle

The current TPS fits into the factory throttle-position sensor location. Fit the sensor supplied with your kit, confirm correct engagement with the throttle spindle and check that the throttle moves freely and returns fully to its stop. Connect the labelled TPS harness connector.

Your experienced Haltech specialist must calibrate the closed and fully open positions in NSP and verify a smooth signal through the complete throttle range before the first start.

4.4 Inline idle control · Cable throttle

The supplied inline idle-control valve fits into the factory air hose that runs from the intake ahead of the throttle body to the back of the plenum.

1. Inspect the existing hose. If it is in good condition, cut it to fit the inline idle-control valve between these two connection points. Replace the hose if it is perished, damaged or unsuitable for the new arrangement.
2. Fit the valve into the hose. Position it clear of the throttle mechanism and check that it does not contact or restrict the throttle through its full range of movement.
3. We recommend removing the original idle-control stepper valve from the side of the plenum near the back, on your left when viewing the engine from the front. Fit the supplied M20 threaded blanking plug into the opening and ensure it seals correctly.
4. Connect the inline idle-control valve to the labelled harness connector. Your experienced Haltech specialist must configure and test idle-control operation before the first start.

Manifold-pressure connection

Connect the manifold-pressure hose to a suitable manifold vacuum source below the throttle plate and route it with the harness to the Nexus R3 MAP connection, following your kit-specific instructions. Keep it sealed, free of kinks and clear of heat and moving parts. Confirm a plausible MAP reading during ECU setup.

4.5 Cam-Sync Sensor

Remove the original distributor and install the supplied cam-sync assembly. Confirm that the drive engages correctly and the O-ring seats without being pinched.

1. Set cylinder 1 to top dead centre (TDC) on its compression stroke.
2. Remove the cam-sync cap so the rotating trigger and fixed sensor can be seen.
3. Clock the assembly so the rotating trigger pickup sits roughly 180° opposite the fixed cam sensor at this engine position. This is the recommended initial mechanical position to help separate the cam trigger event from the crank reference event.
4. Secure the assembly and refit the cap, checking that the final position has not moved.

This initial positioning does not complete the ECU setup. Your experienced Haltech specialist must verify the cam and crank signals, final trigger phasing and base ignition timing before the first start.

4.6 Coolant-Temperature Sensor

Remove the original engine-management coolant sensor and install the supplied Bosch sensor in the specified factory manifold location. Use only a sensor-compatible sealant where required; excessive sealant can affect grounding or contaminate the cooling system.

4.7 Oil-Pressure Sensor

Remove the factory oil-pressure sender from its original threaded port on the side of the timing cover above the oil filter.

Install the supplied banjo fitting and bolt into this port ensuring the washers are present and fitted correctly, then fit the oil-pressure sensor to the banjo fitting. Support the fittings while tightening, orient the assembly clear of any surrounding parts, and verify the applicable thread and torque requirements before installation. Do not overtighten the timing-cover casting.

4.8 Fuel-Pressure Sensor

Install the supplied T-piece in the fuel feed immediately before the fuel rail and install the supplied fuel-pressure sensor. Support the hose and fittings so engine movement cannot load the sensor. Prime and leak-test the complete system before starting the engine.

4.9 LS Coil Brackets and Coils

Remove the original ignition-lead retaining brackets from both rocker covers. Install the supplied Regal Rover Classics LS coil brackets using the supplied bracket-mounting hardware. Minor manipulation of the dipstick may be required for a clean fit. Mount the supplied LS coils using the supplied coil hardware. Route the leads and harness clear of exhaust heat, sharp edges and moving linkages.

4.10 Wideband Oxygen Sensor

One Haltech wideband oxygen sensor is supplied and is all that is required for this installation.

The preferred location is after the two cylinder banks merge, where the sensor samples both banks. It may instead be fitted to one bank, but it will then report only that bank. Use an existing suitable oxygen-sensor bung where available; otherwise, a competent exhaust technician must install a suitable bung.

Mount the sensor in accordance with current Haltech instructions, avoiding a position where condensation can collect on the sensing element. Route the cable away from exhaust heat, driveshafts, suspension movement and road debris. Do not twist the sensor cable during installation.

Route the engine harness

Choose a dry, protected and serviceable ECU location suitable for your vehicle and harness lengths. The factory ECU area may be suitable on a Range Rover Classic or Discovery 1; other vehicles may require a different mounting position. Do not mount it where water, heater leakage, impact or carpet fasteners can damage it.

Route the new harness over the engine and back to the selected ECU position. Where the harness passes through the firewall, use a suitable existing opening and serviceable grommet or arrange a correctly protected bulkhead passage. If reusing the cut factory grommet, leave it loose at this stage. Do not position, bond or tape the grommet until the complete harness has been connected, routed and secured in its final location.

Route the harness before securing it. Connect the labelled branches to:

• fuel injectors;
• crank VR sensor;
• cam-sync sensor;
• intake-air temperature sensor;
• coolant-temperature sensor;
• throttle-position sensor or drive-by-wire throttle body, as supplied;
• oil-pressure sensor;
• fuel-pressure sensor;
• LS coil banks;
• wideband controller; and
• any kit-specific auxiliary connections shown in the pinout book.

Keep sensor and trigger wiring separated from ignition, alternator, starter and other high-current wiring wherever practical. Maintain clearance from exhaust components, belts, pulleys, steering shafts and sharp panel edges. Provide sufficient service loops for engine movement without leaving loose wiring.

Seal the harness bulkhead passage

The factory-grommet repair below applies only where that arrangement is being reused. If your vehicle uses a different ECU location, grommet, gland or bulkhead connector, secure and seal the passage using the appropriate installation method for that arrangement. Do not leave wiring against unprotected panel edges.

1. Confirm that the complete engine harness is in its final position and that no connection is under tension.
2. Locate the cleaned factory grommet correctly on the harness where it naturally aligns with the firewall opening.
3. Refit the grommet around the loom and apply the supplied Loctite 406 sparingly to bond the cut faces. Follow the product safety and curing instructions.
4. After the bond has cured, reinforce and protect the repair with the supplied oil-resistant Tesa engine-bay harness tape.
5. Seat the grommet fully in the firewall and check the repair from both sides.

Loctite 406 forms the bonded joint. The tape provides reinforcement and abrasion protection; it is not a substitute for a properly bonded and seated grommet. If the original grommet is hard, split, distorted or will not seal securely, stop and source a suitable replacement or professional bulkhead solution.

Connect the fuel pump

The Nexus R3 powers the fuel pump from one of its four high-current outputs.

Connect the dedicated fuel-pump power output from the new ECU harness to the pump circuit. Remove or isolate the redundant original pump feed. The pump must receive its power from the new harness.

The Haltech specialist must configure and test pump prime, running control, current limits and automatic shut-off before engine start. Confirm correct polarity, secure terminals and a clean vehicle ground at the pump. Inspect for fuel leaks during priming.

A/C, purge and ignition

Use the vehicle wires labelled and retained before the original ECU and loom were removed. These remain routed to the original ECU location inside the cabin.

For applicable 14CUX vehicles, connect the retained A/C request wire from original ECU pin 21, A/C grant wire from pin 33 and purge-control wire from pin 17 to the matching functions on the new EFI harness. The original 14CUX pin numbers are not the pin numbers of the new Deutsch plug. Use the order-specific harness pinout to identify the new plug cavities and wire colours.

Terminate the retained vehicle wires into the mating connector as shown in your supplied harness pinout, then connect it to the new harness. The existing vehicle wiring continues from this connection to the A/C system and purge valve. Retain the factory relay and protection circuits.

Connect the retained switched-ignition supply to the new harness ignition input. Confirm that the supply is live with ignition on and while cranking, and switches off with the key. This is an activation input only, separate from the ECU’s main battery supply.

For other engine-management systems, identify the equivalent vehicle circuits using the correct factory wiring diagram. A/C and purge connections apply where fitted and included in your order.

The Haltech specialist must verify the configured inputs and outputs, control polarity, compressor protection, idle compensation and purge operation before commissioning.

Main power and earth

Route the main battery positive and negative cables to suit the vehicle, using cable and connections appropriate to the installation and current Haltech requirements. Confirm cable and terminal supply against your order before starting. Terminate the battery ends only after the final route and length are established.

The main fuse and fuse holder are not supplied.

• Route the positive and negative cables by a protected path chosen for the vehicle.
• Trim the cables only after the final route and service allowance are confirmed.
• Crimp the battery-end ring terminals using tooling suitable for the selected cable, then insulate and strain-relieve the terminations.
• Connect the positive feed to the battery through installer-supplied main circuit protection selected and installed in accordance with current Haltech requirements.
• Position the protection device as close to the battery positive source as practicable.
• Connect the ECU negative cable directly to battery negative as specified by current Haltech instructions.
• Do not share the ECU power connection with starter-motor or winch cabling.
• Secure the cables against abrasion, heat, vibration and impact.

No power-cable firewall grommet is supplied and many vehicles have no spare factory penetration. Do not pass an unprotected cable through sheet metal. If a new penetration is required, the installer must provide a correctly sized automotive grommet, gland or insulated bulkhead fitting and protect both sides of the panel.

The vehicle’s switched-ignition circuit is an ECU activation input only. It must not be used to supply the Nexus R3 high-current power, the fuel pump or any other high-current load. The main positive and negative battery cables remain the ECU's main battery power and ground connections.

Do not reconnect the battery until all power connections have been inspected for polarity, insulation, strain relief and circuit protection.

Installer checks

Before reconnecting the battery, confirm:

• every connector matches the pinout book and has been continuity-tested where required;
• power and ground polarity are correct;
• installer-supplied main circuit protection is installed;
• all unused conductors are individually insulated;
• fuel fittings are secure and supported;
• the repaired firewall grommet is bonded, wrapped and fully seated;
• the harness and high-current cables cannot contact heat, sharp edges or moving components;
• the crank trigger, VR sensor and air gap are mechanically complete;
• no tools, loose fasteners or cleaning materials remain in the engine bay; and
• the throttle moves freely and returns correctly.

ECU setup and timing

The installer or owner is responsible for checking the mechanical installation, wiring, fluid connections and fuel system for leaks. The base configuration does not replace ECU setup, verification or tuning. An experienced Haltech specialist must complete the following ECU checks before the first start attempt:

• confirm the ECU firmware and base file are appropriate;
• configure engine capacity, firing order, injector data and fuel type;
• configure crank and cam trigger patterns, sensor type and edge settings;
• disable the injectors in Haltech NSP before cranking for the pre-start checks; keep them disabled while priming and checking fuel pressure, establishing oil pressure, checking trigger synchronisation and setting base ignition timing;
• verify stable engine-speed and synchronisation signals while cranking;
• lock ignition timing and use a timing light to synchronise commanded and measured timing;
• calibrate all pressure and temperature sensors;
• configure and calibrate the throttle or drive-by-wire system;
• configure ignition outputs and dwell;
• configure the high-current fuel-pump output and protection settings;
• configure cooling fans and engine-protection strategies;
• configure A/C request, A/C grant and purge functions where fitted; and
• confirm that every input, output and safety function operates correctly.

First start

With the vehicle secured and suitable fire-safety equipment available:

1. Confirm the injectors are disabled in Haltech NSP, then prime the fuel system and check fuel pressure without starting the engine.
2. Inspect every hose, rail, injector and fitting for leaks. Stop immediately if any leak is found.
3. Confirm realistic oil, fuel, coolant, air-temperature, throttle and battery-voltage readings.
4. Once the commissioning checklist is complete and fuel pressure, oil pressure, trigger synchronisation and base timing have been verified, restore normal ignition timing control and re-enable the injectors in NSP for the first start.
5. Monitor oil pressure, fuel pressure, coolant temperature, lambda, battery voltage, trigger synchronisation and engine protection continuously.
6. Stop immediately for abnormal pressure, temperature, noise, leakage, smoke, unstable synchronisation or incorrect timing.
7. Reinspect all fluid connections and wiring after shutdown.

Before driving

An experienced Haltech specialist must complete the full tune and verify ECU operation. The installer or owner remains responsible for the mechanical installation, wiring security and leak checks. Before driving, confirm:

• safe fuel and ignition calibration across the intended operating range;
• cold start, warm-up, idle and throttle response;
• stable crank and cam synchronisation;
• engine-protection limits and responses;
• fuel-pump, fan and charging-system operation;
• A/C request/grant and purge operation where fitted;
• secure harness routing and firewall sealing; and
• absence of fuel, oil and coolant leaks.

Recheck accessible fasteners, terminals, hose clamps, harness supports and the firewall repair after the first heat cycles.

Support

Email: info@regalroverclassics.com

Resources & links

• Haltech NSP software downloads
• Haltech Nexus manuals and pinouts
• Haltech trigger-system setup reference
• Regal Rover Classics crank-trigger installation guide
• Required crank-trigger fitting video
• Our installation condensed into one minute

Your EFI harness pinout is specific to your harness and supplied with your order. Use it for connector identification and circuit testing.