Cummins V8 is ‘still in development’

The 5-litre V8 diesel engine, originally slated for Chrysler, is ‘currently in development’, according to sources at Cummins Inc. in Columbus, Indiana.

A company spokesman said Cummins was ‘not ready’ to discuss engine details (like bore and stroke) publicly, adding ‘We are currently formulating broad communications plans and would rather not say any more about this engine program at this time’.

He added: ‘As an independent engine supplier, Cummins constantly pursues all potential customers at various levels. In the on-highway world, Cummins typically will let a major OEM announce the availability of our engines before we discuss details of the engine with the media.’

However, two separate and independent sources, including one in Cummins, have pointed to ‘rumours’ of Cummins in discussion with ‘two potential customers’.

The 5-litre V8 would provide Cummins with an opportunity to pioneers its use of compacted graphite iron (CGI) cylinder blocks in the wake of VM Motori and Ford Motor Company.

One Cummins insider claimed the V8 diesel engine program (which was developed in conjunction with a V6 diesel engine following nine years of work with US Department of Energy (DofE) funding) is ‘linked’ to the 2.8-litre I4 engine ‘designed’ by Cummins engineers in Darlington, UK. 

Cummins first revealed the DofE-funded 4.2-litre V6 and 5.6-litre V8 engines in 2008 when it announced it would ‘design and manufacture a family of high-performance, light-duty diesel engines’ with powers of 270bhp and 325bhp respectively, and weights of 663lb and 788lb, again respectively. Both engines used common rail fuelling systems with piezo injectors, EGR and Holset turbochargers.

However, the Cummins spokesman in Indiana noted that ‘at a working level the two programs are not linked in any way’, namely the 2.8-litre I4 and the 5-litre V8.

He added: ‘Cummins works to leverage the best designs and technologies across all of our engineering organisations around the world and there may be unique features utilized on different engines if they are the right choice for both of those engines’.

The Cummins 5-litre V8 diesel engine (designed by a team of engineers in the US) came into prominence again recently when Chrysler announced it had chosen VM Motori’s 3-litre V6 diesel engine for the Ram 1500 pick-up truck – an application at one-time earmarked for the Cummins V8.

                               Lighter weight

The ISF2.8-litre I4 diesel engine was launched in September 2008 at the IAA in Germany in parallel with the ISF3.8-litre. The former is available at 163PS (120kW) while the latter develops 167PS (125kW). The engines, which develop peak torques of 360Nm and 600Nm respectively, are manufactured at a world-class facility in Beijing, China, a joint venture between Cummins Inc. and Beiqi Foton.

Current output for the Beijing Foton Cummins engine plant, following an investment of US$420 million, is believed to be around 80,000 a year. Life-to- overhaul of the engines is 500,000km.

The ISF2.8 is used by GAZ in Russia, JAC in China as well as for the recently unveiled Foton Tunland.

For the tough Australian market Foton stressed the engine as being constructed using the best practices drawn from the ‘diesel engine specialist’s various plants round the world’. The 1-tonne payload Tunland, launched in Australia in December, is similar in size to the Mazda BT-50, the Ford Ranger and the VW Amorak. It is 100mm wider than the Toyota HiLux.

The ISF2.8 is certified only to Euro 3 and Euro 4, although it is Euro 5 and Euro 6 capable. Cummins has no European applications at present for this engine.  Euro 4 has been delayed a couple of times in China and is now planned to be implemented in July this year.

The ISF2.8 is currently available in two formats at Euro 4: EGR for chassis-certified products over 3.5tonnes GVW, such as sports utility vehicles, and with SCR for dynamometer-certified products over 3.5tonnes, such as commercial vehicles.

 It is understood that Euro 6 engines will use both EGR and SCR and eventually will appear in regions such as China. The ISF3.8 was a clean-sheet engine created as the next generation B-series engine.

The more recent ISB4.5 to meet Euro 6 emissions regulations, was designed and developed in the UK from the ISF3.8 and was announced in March 2012, The challenge facing Cummins engineers when moving to Euro 6 was dealing with the additional weight of the EGR system, the Holset (part of Cummins) variable geometry turbocharger and so on, particularly for the four-cylinder product where vehicle weight is more critical.  

The new design has a lower weight cylinder block and head but with the same structural strength as the previous 4.5 engine.  Other design changes such as using composite materials have also helped minimise weight.  This means that the Euro 6 engine is some ten per cent lighter than Euro 5 version even with the added components.

The ISB4.5 is available at 210PS for truck applications and 200PS for bus installations. It has a peak torque of 760Nm.

Cummins’ Darlington plant manufactures engines from 3.9-litres to 9-litres (75bhp to 400bhp) – essentially B-series, C-series and L-series. Production is running at around 40,000 a year and key customers are Daf, Alexander Dennis, Optare, WrightBus, VDL (including the new bus for Transport for London) Komatsu, JCB and Hyster.

                                  The future?

Meanwhile, back on the topic of Chrysler’s family of Ram pick-up trucks it remains to be seen if the Cummins V8 engine will find a home somewhere in Chrysler’s Super Duty range, for example 2500, 3500, etc.

For example, while all the major US OEMs in this sector compete on pulling power, not all Super Duty owners need the pulling power of the Cummins 6.7-litre engine. So is it possible that Chrysler, in seeking further ‘downsizing’, might be convinced there is a market for a 5-litre V8, thus offering its Ram yet another ‘coup’ in fuel economy, while at the same time finding a niche to retain its ‘long-term’ supplier Cummins. 

On the other hand, there is a view within Cummins that the market for Ram 2500, 3500 etc vehicles is changing; that more small businesses like farming, construction and so on are switching to vehicles that need the torque of the 6.7-litre engine.

The question remains: Would there be enough production volume in this for Cummins to justify offering Chrysler the V8 at a competitive price? Only time will tell.

However, since Cummins has just completed its second-best financial year, the Columbus-based engine maker may feel it can afford to continue to ‘mark time’, leaving its 5-litre engine 'on the shelf' until one, or both, of the much rumoured customers comes to the table for its long-in-development V8 diesel engine.     ∎