RJ70 Holden V8

Marks 4WD Adaptors manufacture kits that allow the fitting of the Holden 304, 308, and 350 C.I. V8 engines.

To comply with Australian emission laws the new engine must have been manufactured the same year or later than the vehicle. The engine must also have all of the emission components connected, including the catalytic converter. The engine must also be run on unleaded fuel or LPG.

In Australia an engineer's report is required after the conversion has been completed. Contact your local RTA office for a list of engineers.

Marks 4WD Adaptors manufacture a conversion kits to allow the fitting of Holden V8 engines to the Bundera 5-speed gearbox.

These vehicles equipped with the 22R petrol engines have a 5-speed G52 gearbox which is marginal in strength and should be taken into consideration if you intend using the vehicle for heavy towing or if you plan to use a high output engine.

Vehicles fitted with the Turbo charged 4-cylinder diesel engines are fitted with a stronger gearbox than the G52 gearbox. This gearbox is based on a Toyota Dyna truck 5-speed and is strong enough to handle the power of a V8 engine.

Holden V8 engines are available with two bellhousing bolt patterns all 253 C.I. engines have the Holden Trimatic bolt pattern.

The 308 C.I. engines are available with the Turbo or Trimatic bolt patterns.

The 1988 VN and later 304 C.I. and 350 C.I. engines have the Turbo bolt pattern.

The bolt patterns are illustrated below.

Chevy Turbo bolt pattern. Holden Trimatic bolt pattern.

Bellhousing

The bellhousing has been designed to accept the Toyota pressed metal clutch fork, clutch fork pivot, clutch fork boot and slave cylinder (mounted on the right hand side). When replacing the Toyota diesel engine a petrol model slave cylinder will need to be purchased. The Toyota clutch master cylinder is retained for the conversion.

Clutch

We recommend using a GM 10" or 10.5" pressure plate with a Toyota 10" clutch disc. Marks 4WD Adaptors stock these special clutch kits.

The GM engine can be fitted to the vehicle without the need to reposition the transmission, modify the firewall, or alter drive shaft lengths.

Clutch Hydraulics

The Toyota clutch slave cylinder does not have enough stroke for correct operation. To overcome this problem Marks 4WD Adaptors manufacture a kit which increases the stroke of the slave cylinder, the kit includes a new master cylinder firewall adaptor and push rod adaptor.

Engine Mounting

Engine mounts are available for the Holden V8 engine conversion kits. The engine mount brackets have been designed to bolt to the engine block and fit to the Toyota mounting rubbers.

Engine Sump

The engine sump will need to be modified to allow the front suspension components such as the differential and the front drive shaft to clear when the suspension is fully compressed.

Radiator

The original Toyota radiator will not adequately cool a Holden V8 engine we recommend using a modified Holden HQ radiator or a custom made aluminium radiator.

BCM

Commodore VR and VS engine computers (PCM's) require a security signal from the body control module before the engine can be started. The BCM simulator is programmed to supply the correct security signal allowing the engine to be started.

The simulator is programmed to send both VR and VS security codes.

The simulator is also equipped with an output to control a relay for the engine cooling fan. This option will only work with VS models.

PCM Mem-Cals

Commodore VT engine management computers require a stream of data to be sent to them from the body control module, prior to starting the engine. This is part of the vehicles anti theft system. The stream of data required by the PCM is special. Fortunately the input to the PCM can be switched off by changing the program information in the mem-cal. Marks 4WD Adaptors can supply mem-cals on an exchange or out right basis.