New Big Mack Choice for the Magnum

[kscarbel2]

Commercial Motor / October 3, 1996

As reported last week, Renault has introduced its US Mack E7-hased engine range in the Renault Magnum, The engine introduces a third power rating, boosting maximum output to 464hp from 12 litres and plugging the gap between 420hp and the 520hp 16-litre Mack vee-eight.

Although the new 12-litre is based on the Mack E7, only the block, heads and crankshaft drives are sourced from Mack in the US—the engine is called the Renault E7. The fuel pump, injection circuit, turbocharger and engine Jake Brake are mounted at Renault's plant near Lyon in France.

The wiring is made at the French plant and accessories such as the alternator, air compressor, power steering pump, starter motor, man ifolding and pipes are sourced from existing Renault supplier.

The result is an engine which weighs in at 1,085kg, 115kg less than the 12-litre Renault engine it replaces. The net weight saving in the Euro-2 Magnum is 70kg. Although torque is increased, it is still less than the US variants of the engine which produce up to 1,560lb.ft. (2,115Nm) at 1250rpm.

Articulated pistons have steel crowns and aluminium skirts; the fuel system uses a Bosch P8500 in-line pump with EDC and eight-hole injectors. Injection timing is also electronically controlled by the VMAC engine management system.

VMAC offers a number of features which control the engine and assist vehicle management. Engine controls include idle speed adjust, engine Jake brake control and engine protection shutdown if coolant temperature rises too high. Other features include cruise control, engine speed control, speed limiter, interface with ABS and anti-skid systems and a limp-home capability. A serial data link allows diagnostic information to be downloaded to a PC.

Mack-powered Magnums go on sale in the UK straight away in 385hp and 424hp ratings— the 464hp version will not be available until next spring.

.