History of the K K-Series PG1 Gearbox VVC Engine KV6 LPG Fuels LPG Fuelled Cars Engine Applications

The "K" Series engine has its roots in the 1980’s when it won government funding from politicians renowned for their dislike of state support for the manufacturing industry. The elegance of its design, with one set of bolts clamping the whole engine together, is still considered to be world class in many respects.

The major components of the unit – the four "Cs" – are largely produced in-house. Castings for the cylinder block and cylinder head are made from raw aluminium billets using the patented LPS (Low-Pressure Sand) process in the Foundry. The transformation of these raw castings into machined components also takes place on-site in East Works. Forged blanks are bought in as the starting point for crankshafts and camshafts. Precision turning, grinding and finishing transforms these blanks into the heart and soul of the engine. Following these parts through the assembly process is not as easy as you might think. There are two assembly tracks running side-by-side. One of these does a subterranean "U" turn half way through. Between and around the lines are sub-assembly loops for manifolds and cylinder heads obscuring the overall pattern.

Sophistication in the process takes many forms. Automatic assembly of valve train components hides behind unassuming metal panels. Selection of different grades of bearing to suit individual combinations of crankshaft, cylinder block and connecting rods ensures the highest level of refinement. Mechanical and electrical tests ensure no faults pass forward down the lines. Continuous improvement of assembly line facilities and tooling ensures that the quality of the product has continually improved since its first shift in 1989. A very high proportion of engines are produced "right first time".

More amazing than its manufacture is the power output of this unit. What started out as a weight - and strength - optimised 1400cc with 1100cc younger brother has grown up through 1600cc and 1800cc variants to become the VVC (Variable Valve Control) unit developing more than twice as much power than originally planned. This goes some way towards explaining why "K" Series engines have been adopted for so many small high performance vehicles such as the Lotus Elise.


Following its successful production debut, the "K" Series engine donated many of its internal components and geometry to the KV6, which followed it through the engineering test beds. This engine successfully justified its transformation into a volume product when it replaced the V6 engine bought from Honda for the Rover 800.

In volume and overall length terms, it is one of the smallest on the market: a fact which makes it admirably suitable for front wheel drive vehicles. The methods used for the production of its major components have evolved from those used on the "K" Series engine and remain predominantly "in-house". Final assembly takes place on a dedicated asynchronous track running in an easy to follow circle. Units earmarked for rectification by in process validation are diverted onto loops like railway sidings. The whole process is supported by a sophisticated pallet system. Since 2001 the KV6 has now been allowed to shine in uprated forms as the power behind the new MG-ZS and ZT models.

PG1 Gearbox

Longest serving in the current Powertrain product line-up is the PG1 gearbox. With its roots in the Honda-designed HX5MT unit supplied for the original Rover 800, the gearbox has benefited from continuous improvement over the years resulting in progressively higher levels of customer satisfaction.

Only a few small components are still sourced from Japan. The aluminium casings come in as raw castings. Most of the gears and both shafts come in as rough forgings to be machined, heat-treated and finished by in-house processes.

Compared to the engines, the gearbox assembly process is a short and sweet affair involving barely half a dozen stations. Sophistication comes in the form of acoustic test rigs, which check all finished assemblies to make sure none exceed the noise standards set for the vehicles. In the last twelve months this product has been specified for use in the MG-ZS and the MGF 1600cc.

Low Pressure Sand (LPS) Casting Foundary

A manufacturing unit of approximately 5,000 square metres, which is situated South of the main Longbridge Site at the Cofton Hackett end of East Works.

LPS has been in production since 1988 manufacturing major aluminum components for K Series Engines, including Cylinder Heads and Cylinder Blocks for K4 and VVC Engines and Cylinder Heads for KV6.

The facility is organised into 4 major processes:-

  • Core Shop

  • Casting Area

  • Heat Treatment

  • Finishing

Powertrain’s LPS (Low Pressure Sandcasting) Foundry was conceived in response to a demand for a casting process that could supply the thin-walled, lightweight, aluminium cylinder head and block on which the K Series Engine family concept was based.

Both the process and facilities were designed and developed to be at the forefront of foundry technology, without which the engine designers’ visions could not have become reality.

The casting process involves the use of a special electromagnetic pump to fill precision sand moulds under closely controlled process conditions leading to enviable levels of quality and efficiency.

The process has also proved itself to be extremely versatile, accommodating over the years since the original introduction of K Series numerous design changes and new product introductions. Alongside Cylinder Heads and Blocks for the complete K4 Engine range, including VVC, the Foundry also produces the Cylinder Heads for the KV6 family of engines. At other times during its life, clutch housings for transmission products have been produced as have complex prototype and pre-series cylinder heads for BMW.

Located as it is, less than a hundred metres from a local residential area, environmental considerations have been at the forefront of activity in the foundry with the result being the complete satisfaction of the requirements of regulatory authorities.

So, after many of years of volume production which have seen the evolution of both the products and processes within the facility, the LPS foundry remains an integral part of the K Series story.