MCE-5 VCRi: Pushing back the fuel consumption reduction limits

It’s ready

The MCE‑5 VCRi is an essential element of the technological mix applied to
gasoline engines, to meet the 2020-2025 objectives for automobile emission reductions

It can take up to 20 years and sometimes longer to develop a new engine. With that long a lead time, it would be difficult to predict the economic, energy, environmental and regulatory context when the new engine is ready for production. To avoid the dead end of a poorly adapted engine, it is essential for carmakers to explore different technological options capable of adapting to diverse scenarios, from the most probable to the least probable.

10 years of R&D were necessary to go from the
MCE‑5 principle to the first multi-cylinder engine

The MCE‑5 VCRi is no exception:
R&D is long, risky and costly

Forging of piston racks. MCE‑5 VCRi
is a technology with extremely low
residual functional or industrial risks

4 cylinder bi-turbo MCE‑5 VCRi are running
on the test bench in MPFI or GDI versions

It is hard to develop a new type of engine, to such an extent that very promising ideas can turn into failures for reasons that may have been impossible to predict. It is for that reason that an exhaustive technical demonstration is required, which takes into account all criteria and leaves none out. An engine that is too loud, too big, too costly, not sufficiently energy efficient or highly polluting will be abandoned for functional, industrial or economic reasons. Even if a decision were made to go ahead and produce this technology, it would be sanctioned by the market, by the regulations or by both.

These technical demonstrations require Research & Development (R&D) efforts over many years. R&D is costly, risky and takes up a lot of time and human resources. Sometime 4, 5, even 10 technological approaches must be developed to identify a single one capable of being brought to market. This requires substantial investments over very long periods.

Today, cars really use very few technological approaches to ensure the success of their core market: the gasoline engine. These essentially include direct gasoline injection coupled with supercharging and Variable Valve Actuation (VVA). External EGR is also more marginally one of the possible evolutions. Hybridization is more a transmission system than an actual engine: the only primary energy converter on the vehicle remains the IC engine. Other than recovering a part of the energy lost during braking, hybridization has no other function than to avoid using the IC engine at very low power, when the efficiency is really poor. It is clear that if the efficiency of the IC engine was excellent through its whole range of use, hybridization would be of no use: it’s the efficiency of the IC engine that must above all be improved.

GDI turbo, VVA and external EGR are effective but insufficient to reach 95g of CO2/km in 2020 and 70g in 2025 without redefining the vehicles themselves. If no solution is found to improve IC engine efficiency during this period, we will see a progressive deterioration in vehicle performance. Indeed, without affordable, fuel-efficient and high-performance IC engines, reducing performance levels will be the only way to reduce greenhouse gas emissions in the targeted manner. This would be done at the cost of seeing the progressive disappearance of high-end cars and the deterioration of the profitability of the whole automotive sector. This would be accompanied by a degraded image of cars which would no longer be an object of pleasure and social standing but simply a means of going from A to B.

These considerations give MCE‑5 VCRi technology all its value. Its effectiveness has been proven and it constitutes the “missing link” in the energy efficiency of gasoline engines. Its intrinsic qualities can reduce fuel consumption beyond what is possible with direct gasoline injection, supercharging and VVA. Combined with these technologies, the intelligent variable compression ratio put forward by MCE‑5 VCRi technology will allow an additional fuel consumption reduction of at least 10% on the smallest vehicles and up to 35% for large high-performance vehicles.

The result of 12 years of intensive R&D, MCE‑5 VCRi is a technology with extremely low residual functional or industrial risks. The MCE‑5 VCRi engines exist in single-cylinder, in 4-cylinder with two-stage turbocharging and in direct gasoline injection versions. MCE‑5 VCRi demo cars are currently running. The results obtained go well beyond the initial objectives set by MCE‑5 DEVELOPMENT in 2000. MCE‑5 VCRi technology has been backed for over 10 years now by the French State and brings together a consortium of companies capable of mass-producing it by 2015-2016. The first engines compliant with the specifications of certain carmakers, will be ready to enter into an industrialization process as of 2014. The MCE‑5 VCRi engine can be integrated into all types of vehicles without any modifications to the chassis. It is transparent for the end user and will be ready for mass-production when the most constraining fuel consumption reduction standards and objectives are applied in Europe and the USA.

The fact that it is ready to enter into an industrial development process makes MCE‑5 VCRi technology a credible option in the short term for a rapid evolution in automobile engines.