Rover K-series engine
The Rover K-series engine is a series of engines built by Powertrain Ltd, a sister company of MG Rover. The engine was a straight-four cylinder built in two forms, SOHC and DOHC, ranging from.
Design history
The K series was introduced in 1988 by Rover Group as a powerplant for the Rover 200 car. It was the second volume-production implementation of the low-pressure sand-casting technique in a new plant sited between East Works and Cofton Hackett.. The LPS process pumped liquid aluminium into a chemically-bonded sand mould from below. This reduced oxide inclusions and gave a casting yield of around 90%, compared with 60% for more conventional gravity casting processes. The process avoided many of the inherent problems of casting aluminium components and consequently permitted lower casting wall thickness and higher strength-to-weight ratios. However, the process required the use of heat-treated LM25 material which gave the engines a reputation for being fragile. An engine overheat would often result in the material becoming annealed and rendering the components scrap. The layout of the engine bay on some Rover cars fitted with K-series engines – particularly the MGF with its mid-engined layout – means that a commonly-occurring coolant leak under the inlet manifold can go undetected until severe damage has been done to the head. The aluminium engine blocks were fitted with spun-cast iron cylinder liners that were initially manufactured by GKN's Sheepbridge Stokes of Chesterfield, but these were replaced by liners made by Goetze after some seminal research conducted by Charles Bernstein at Longbridge, which proved influential even to Ducati for their race engines. Unfortunately a large number of aftermarket engines, the so-called "VHPDs", were built with the old substandard GKN liners by Minister, Lotus and PTP well after the introduction of the Goetze liners to production in 2000.The engine was introduced initially in 1.1-litre single overhead cam and 1.4-litre dual overhead cam versions. Because Honda stopped providing Rover with engines after the end of their relationship, but well before the BMW takeover, an enlargement of the K Series design to 1.6 and 1.8 litres was carried out. This was done by using larger diameter cylinder liners and also increasing the stroke. The change required a block redesign with the removal of the cylinder block's top deck and a change from "wet" liners to "damp" liners. The plastic throttle body fitted to the engine until 2001 was manufactured by the SU Carburettor company. They also included aluminium and larger sized bodies.
The four-cylinder engines were held together as a sandwich of components by long through-bolts which held the engine under compression, though this construction is not unknown, and was used in early lightweight fighter engines from the First World War. It had also been used in motorcycle engines and Triumph Car's "Sabrina" race engine.
The two types of head that were bolted to the common four-cylinder block were designated K8 and K16. A later head design also incorporated a Rover-designed Variable Valve Control unit. This allowed more power to be developed without compromising low-speed torque and flexibility. The VVC system constantly alters the inlet cam period, resulting in a remarkably flexible drive: the torque curve of a VVC K-series engine is virtually flat throughout the rev range and power climbs steadily with no fall-off whatsoever until the rev limiter kicks in at 7,200 rpm.
Following the collapse of MG Rover in 2005, the K Series engine started a new and rather interesting chapter in its history.
Two separate re-developments of the engine were taking place by at the time two rival Chinese car firms.
The Chinese automaker Nanjing Automobile purchased the assets of MG Rover and in doing so acquired use of the Longbridge plant and the intellectual property rights and production tooling to many designs, including those of the K series engine.
With the help of Lotus Engineering, NAC went on to produce the N Series an improved version of the K Series with redesigned headgasket and oil rail built on the original tooling.
This engine featured in the relaunched MG TF in the UK and the MG3 SW and MG7 in China. Contrary to popular belief, the N Series was never fitted to the MG 6.
When the MG TF ceased production for the final time in 2011, so did the N Series.
The second development was by the larger Chinese conglomerate SAIC Motor. SAIC had also previously purchased the rights and blueprints to several of MG Rovers designs. Whilst they had the necessary knowhow they didn't have any tooling so had to essentially reverse engineer their version of the engine.
The advantage of this was it allowed Ricardo 2010, the company tasked by SAIC to carry out development the opportunity to improve the engine in a number of areas.
The main area's of improvement included the head being redesigned to improve the waterways and structural rigidity and the block was also strengthened.
All new tooling was used in its production and the quality of materials and that of the aluminium casting process created a much more substantial update than that of the N Series.
This new engine would go on to power the Roewe 750, the Roewe 550 and later after the two firms NAC and SAIC merged, The MG 6.
Engine management
K8 engine
Early K8 engines used a single SU KIF carburetor with a manual choke and a breaker-less distributor mounted on the end of the camshaft. MEMS Single-point injection became standard with the launch of the Rover 100 in 1994.K16
K16 models used MEMS, with a 1.6 ECU from 1990 until 1994 and a 1.9 ECU from 1995 onwards, in either Single Point or Multi Point forms, with a single coil on the back of the engine block and a distributor cap and rotor arm on the end of the inlet camshaft. MEMS 2J was used on the VVC engine, to control the Variable Valve Control and the Distributorless Ignition System, which was used because there were camshaft drive belts at both ends of the engine. With the launch of the Rover 25 and Rover 45 in 1999, MEMS 3 was introduced, with twin coils and sequential injection.Model range
1100
All 1100 engines displace with bore X stroke of 75 mm × 63 mm. Four variations were created:- SOHC K8 8-valve, Carburettor,
- SOHC K8 8-valve, SPI,
- SOHC K8 8-valve, MPI,
- DOHC K16 16-valve, MPI,
- Rover Metro
- Rover 100
- Rover 200
- Rover 25
1400
All 1400 engines displace. Six variations were created:
- SOHC K8 8-valve, Carburettor,
- SOHC K8 8-valve, SPI,
- SOHC K8 8-valve, MPI,
- DOHC K16 16-valve, SPI,
- DOHC K16 16-valve, MPI,
- DOHC K16 16-valve, MPI,
Cars that came with the 1400:
- Rover Metro
- Rover 100
- Rover 200
- Rover 25
- Rover 400
- Rover 45
- Rover Streetwise
- MG ZR
- MG ZS – Ireland and Portugal only
- Caterham Seven
- GTM Libra
- GTM K3
- FSO Polonez Caro/Atu
- Reliant Scimitar Sabre
1600
All 1600 engines displace and have DOHC, 16 valves and MPI. Two variations were created:
Cars that came with the 1600:
- Rover 200
- Rover 25
- Rover Streetwise
- Rover 400
- Rover 45
- MG ZS
- MG F
- MG TF
- Caterham Seven
- Caterham 21
1800
The 1.8 engine is the largest the engine displaces. All 1800 engines displace with bore X stroke of DOHC 4 valves per cylinder and MPI.
Non-VVC :
Naturally Aspirated:
The base engine, the engine made @ 5600 rpm and @ 3500 rpm of torque or in slightly tuned at @ 6750 rpm/ @ 3000 rpm in the MG TF
Years | Model |
1995-99 | Rover 200 |
1999-05 | Rover 25 |
1999-05 | Rover 45 |
1998-05 | Rover 75 |
2003–05 | Rover Streetwise |
2001-05 | MG ZR |
2001-05 | MG ZS |
2001-05 | MG ZT |
1995–05 | MG F |
1997–06 | Land Rover Freelander |
1996-05 | Caterham Seven |
1996–99 | Caterham 21 |
Turbocharged:
The 1.8 Turbo was developed to replaced the 2.0 Rover KV6 engine due to emissions and fuel economy, the engine is turbocharged and made
- 2000-2005 Rover 75
- 2001-2005 MG ZT
The VVC engine came in three variant:
- The early VVC produced @ 7000 rpm / @4500 rpm
Years | Model |
1995-99 | Rover 200 |
1995-99 | Rover 200 Coupe |
1999-05 | Rover 25 |
1995–05 | MG F / MG TF |
1996-05 | Caterham Seven |
1996–99 | Caterham 21 |
- Rover later tuned the VVC to produced @ 7000 rpm / @4700 rpm
Years | Model |
2001-05 | MG ZR |
2001-05 | MG ZS |
2001-05 | MG ZT |
1995–05 | MG F / MG TF |
1996-05 | Caterham Seven |
1996–99 | Caterham 21 |
- VHPD – Very-high-performance derivative, .
Years | Model |
1996-06 | Lotus Elise |
2000-04 | Lotus Exige |
2000 | Lotus 340R |
1996-05 | Caterham Seven |
1996–99 | Caterham 21 |