General

Normally Aspirated Engine





Supercharged Engine

The AJ27 power unit is available in 4.0 L versions, and comprises:
An eight cylinder 90 degree "V" configuration liquid cooled aluminum cylinder block incorporating "Nikasil" plated cylinder bores.
Pistons of open-ended skirt design, with two compression and one oil control ring.
Two aluminum cylinder heads, each incorporating two camshafts.
Four valves per cylinder. Aluminum valve lifters and top mounted shims.
Variable valve timing (VVT) of the intake camshafts (normally aspirated only).
Camshaft covers manufactured from Vinylester.
Aluminum timing cover which accommodates the crankshaft front oil seal.
Single row primary and secondary chains drive the camshafts of each cylinder bank.
An aluminium bed plate, incorporating iron main bearing supports, which accommodate the oil pump pick-up, diverter valve (if fitted) and oil filter.
Main bearings which are grooved in the upper positions and plain in the lower positions. They are manufactured from aluminum/tin material.
A crankshaft with undercuts and rolled fillets for extra strength.
Fracture-split connecting rods in sintered-forged steel.
Brackets bolted to the front of the cylinder block are used to mount all accessories.
A single, seven ribbed vee belt drives the front end accessories on all versions of the engine.
A second, seven ribbed vee belt drives the supercharger.
Automatic belt tensioners - one for the front end accessory drive and one for the supercharger where fitted. Each tensioner incorporates a belt wear indicator.
An advanced engine management system incorporating electronic throttle control.
The unit meets the requirements of the CARB OBDII USA legislation.

Ancillary Systems
The ancillary systems, driven by the engine, each have a detailed Description and Operation along with Diagnostic Procedures, and Removal and Installation instructions; refer to the following:
Power Steering Pump. Refer to Steering and Suspension.
Air Conditioning Compressor. Refer to Heating and Air Conditioning.
Engine Cooling Pump. Refer to Cooling System.
Generator. Refer to Starting and Charging.
The drive belt, idler pulley and automatic tensioner are described under Drive Belts, Mounts, Brackets and Accessories.
The engine starting system is described under Starting and Charging.