Renault Energy dCi 130: F1 on the road

Renault is one of the most successful F1 engine makers of recent years.

Be it Williams, Renault (Lotus?) itself or now Red Bull, the firm’s Formula 1 engines have powered countless race wins, plus a hefty haul of World Driver and Constructor titles.

All this expenditure must be justified though, which is why car makers oft witter on about their F1 programmes driving what happens on the road. Indeed, we all think: like a Renault Clio 200 really is about to get a 2.4-litre V8.

But finally, Renault has revealed exactly how F1 can help road car programmes – with the headline-grabber being it’s giving us the most powerful (yet green) 1.6-litre diesel engine ever sold. Cue the 1.6 Energy dCi 130: the most advanced mid-range diesel yet built?


Renault wants to cut its range CO2 average from today’s 135g/km to below 120g/km in 2013, and below 100g/km come 2016. To do this, it needs new engines, with big incremental CO2 falls. Renault says its new Energy engines must cut CO2 by 30-40g/km over the motor they replace.

The R9M 1.6 Energy dCi 130, on paper, does this: 30g/km less CO2 and 20% better fuel economy than the 1.9 dCi 130 FQ9 it replaces. Design work started in 2006 and it was a clean-sheet design that generated 30 patents.

Of its 264 components, 75% are new: the rest mostly come from the MR9 2.0 dCi 150. There are also six specific CO2-reducing technologies, that together drop CO2 by that 20% total.

F1 link

The F1 link is genuine. Engineers from RenaultSport F1 in Viry-Chatillon worked with road car engine designers in Rueil to transfer F1 tech to the road.

Philippe Coblence managed the R9M project at Rueil – and formerly did the same at Viry-Chatillon for F1 engines in the early 2000s. He facilitated the technology transfer, and helped deliver three key areas of F1 engine thinking in the design of the 1.6 Energy dCi 130.

1: Square

Matching bore and stroke is loved by F1 engineers and is also present here. It allows large diameter valves to be used, which fill the combustion chambers more efficiently.

2: Water flow

Transverse water flow* is a common in F1. It means smaller water pumps can be used. Renault has combined it with a double water jacket, allowing a controlled flow of water can be focused solely on the hot zones – combustion chamber, injectors – and cools each cylinder equally.

As water is fed downstream of the water pump, it does not flow round the combustion cylinders, meaning the cylinder head is cooled more efficiently. Water flows ‘natrually’ round the system too, with no obstructions, meaning less wasted fuel.

3: Internal friction

Super-finished surfaces and UFLEX piston ring technology have both been used, after featuring in F1 for the past decade. UFLEX is, says Renault, like a multi-blade razor: it adapts to contours and does not exert undue pressure – maximum efficiency, minimum friction.

Low-pressure EGR

Most Exhaust Gas Recirculation systems are high pressure. They take exhaust gas from the combustion chamber almost as soon as it leaves, and inject this hot gas straight into the air intake. This reduces NOx but raises the intake pressure, restricting turbo pressure.

The 1.6 Energy dCi 130 has low-pressure EGR. This is far more complicated. Exhaust gases are recovered much further downstream, after they’ve been through both the turbine and particulate filter. They are cooled in an intercooler, then recirculated through the turbo to increase its pressure.

They are then cooled a second time, before re-entering the air intake. This ‘cold loop’ means the recirculation rate can be increased, further improving efficiency and reducing NOx levels.

Remember how turbocharged engines perform better on cold days, because the air density is higher? The same applies here.

The 1.6 Energy dCi 130 allows it because the distance between the catalyst, particulate filter and air intake is so short.

Thermal management

Cold engines – below 80deg C – are inefficient: combustion is incomplete and cold lubricant is more viscous, increasing friction.

Renault helps the engine warm up 3 minutes faster by using a valve in the cooling circuit. This is closed when it’s cold, so water can’t circulate through the engine, around the combustion chambers. The engine thus warms up faster. Water does, however, flow round the engine: that double jacket coming into play again.

When warm, the solenoid opens. And when it’s really warn, the thermostat opens, engaging the entire cooling circuit. The transverse flow of water is F1-derived and results in a simpler thermal management system that’s consistent and effective. A direct Renault F1 crossover to road cars.

Other stuff

  • Renault claims swift variable-geometry turbo response from low revs, that’s so good, the technology behind it has been patented.
  • The compression ratio is lower, for fewer emissions, with performance maintained by a higher turbo pressure: 2.7 bar is a 12% increase.
  • Injection pressure is capped to 1600 bar, rather than 1800 bar, so smaller components can be used.
  • The engine is the first to benefit from full work by Renault’s new NVH department: Renault says it’s as refined as a D-sector vehicle.
  • 160 engineers worked on the engine, which took 32 months to complete. 76% new, the project cost €230m.
  • Downsizing from 1.9 to 1.6 reduces the swept volume of each cylinder by 16%.

Although the Energy dCi 130 programme was co-funded by Alliance partner Nissan, Renault led development through being the ‘acknowledged diesel specialist’ of the two. Unlike Nissan, it was also able to call upon an in-house F1 programme, and it’s this learning that’s been applied here.

It’s easy to scoff at such claims of F1 technology transfer, but here, Renault given proof positive that race track learning really can benefit road cars – with 64.2mpg and 115g/km being a benefit all of us can enjoy.

Now, Renault, just bring on the Megane Coupe Lotus Energy dCi 130 launch special.

* Transverse water flow explained: Most engines use longitudinal coolant flow: it enters at one side of the cylinder head and flows through the entire head before exiting. See the problem? Yes – cylinder 1 heats up the coolant before it reaches cylinder 2, and so on. Poor cylinder 4.

Transverse flow sees coolant enter the side of the engine, with the return at the opposite side of the cylinder head. Each cylinder is separated from the others to avoid interference. Result? No heat soak from one cylinder to the next, making it much more efficient.

Longitudinal is commonplace, as it’s easier to cast and thus mass-produce. Transverse is better, though. In which direction does the coolant in your engine flow? Have you ever even considered it? I’m thinking not…

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