So. Einen so schönen Vergleichstest wie aus der Studie mit dem 4.2er Audi konnte ich leider nicht finden. Allgemein besteht wohl im Forschungsbereich relativ wenig Interesse daran die bereits vorhanden Produkte genauer zu untersuchen. Außer den "Studien" die in diesem Bereich von den Herstellern selbst beauftragt werden und daher kaum als objektive Untersuchung gewertet werden können, konnte ich jetzt nichts auftun.
Wissenschaftliche Arbeiten und Studien scheinen sich aktuell eher mit dem Umwelteinfluss oder aber der Effizienzsteigerung durch die bestmögliche Nutzung von hoch-oktanigen Kraftstoffen zu befassen. Daraus wiederum lässt sich für mich ableiten, dass Fahrzeughersteller zum aktuellen Zeitpunkt diese Potenziale wohl in Serienfahrzeugen nicht ausnutzen.
Leider darf ich euch die gesamten wissenschaftlichen Arbeiten hier nicht anhängen, aber ich gebe euch mal die Titel und die Abstracts, sodass ihr selbst anlesen könnt in welche Richtung das ganze geht:
Maximizing the benefits of high octane fuels in spark-ignition engines
Fuel Technology R&D Division, Saudi Aramco Research & Development Center, P.O. Box 62, Dhahran 31311, Saudi Arabia
In Fuel 1 November 2017 207:470-487
Morganti, Kai ⁎,
Viollet, Yoann,
Head, Robert,
Kalghatgi, Gautam,
Al-Abdullah, Marwan,
Alzubail, Abdullah
Highlights •Octane-on-Demand was compared with two gasolines containing ethanol (E10 and E30).•Specific fuel consumption was reduced by up to 10% with respect to the E30 gasoline.•Methanol was more effective at suppressing knock than ethanol.•Efficiency and specific fuel consumption can be decoupled in dual-fuel engines.•Minimizing specific fuel consumption marginally increased the specific CO2 emissions.
Redirecting
Das hier geht eher in die Gegenrichtung, aber immer noch im gleichen Themenbereich
Compression ignition of low-octane gasoline: Life cycle energy consumption and greenhouse gas emissions
State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China
In Applied Energy 1 November 2016 181:391-398
Hao, Han,
Liu, Feiqi,
Liu, Zongwei,
Zhao, Fuquan
Highlights •A process-based, well-to-wheel conceptualized life cycle assessment model is established.•The impacts of using low-octane gasoline on compression ignition engines are examined.•Life cycle energy consumption and GHG emissions reductions are 24.6% and 21.6%.•Significant technical and market barriers are still to be overcome.
Redirecting
Hierbei geht's eher um Zusätze als um Premiumkraftstoffe:
Performance and emissions of gasoline blended with terpineol as an octane booster
Clean Combustion Research Center (CCRC), Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
In Renewable Energy February 2017 101:1087-1093
Vallinayagam, R. ∗,
Vedharaj, S.,
Roberts, William L.,
Dibble, Robert W.,
Sarathy, S. Mani
This study investigates the effect of using terpineol as an octane booster for gasoline fuel. Unlike ethanol, terpineol is a high energy density biofuel that is unlikely to result in increased volumetric fuel consumption when used in engines. In this study, terpineol is added to non-oxygenated FACE F gasoline (Research Octane Number = 94.5) in volumetric proportions of 10%, 20% and 30% and tested in a single cylinder spark ignited engine. The performance of terpineol blended fuels are compared against a standard oxygenated EURO V (ethanol blended) gasoline. It was determined that the addition of terpineol to FACE F gasoline enhanced the octane number of the blend, resulting in improved brake thermal efficiency and total fuel consumption. For FACE F + 30% terpineol, break thermal efficiency was improved by 12.1% over FACE F gasoline at full load for maximum brake torque operating point, and similar performance as EURO V gasoline was achieved. Due to its high energy density, total fuel consumption was reduced by 6.2% and 9.7% with 30% terpineol in the blend when compared to FACE F gasoline at low and full load conditions, respectively. Gaseous emissions such as total hydrocarbon and carbon monoxide emission were reduced by 36.8% and 22.7% for FACE F + 30% terpineol compared to FACE F gasoline at full load condition. On the other hand, nitrogen oxide and soot emissions are increased for terpineol blended FACE F gasoline when compared to FACE F and EURO V gasoline.
Das aussagekräftigste für die Fragestellung die in Foren immer wieder auftaucht dürfte wohl noch das hier sein:
Effects of High Octane Ethanol Blends on Four Legacy Flex-Fuel Vehicles, and a Turbocharged GDI Vehicle
Huff, Shean [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)]
2015
The U.S. Department of Energy (DOE) is supporting engine and vehicle research to investigate the potential of high-octane fuels to improve fuel economy. Ethanol has very high research octane number (RON) and heat of vaporization (HoV), properties that make it an excellent spark ignition engine fuel. The prospects of increasing both the ethanol content and the octane number of the gasoline pool has the potential to enable improved fuel economy in future vehicles with downsized, downsped engines. This report describes a small study to explore the potential performance benefits of high octane ethanol blends in the legacy fleet. There are over 17 million flex-fuel vehicles (FFVs) on the road today in the United States, vehicles capable of using any fuel from E0 to E85. If a future high-octane blend for dedicated vehicles is on the horizon, the nation is faced with the classic chicken-and-egg dilemma. If today’s FFVs can see a performance advantage with a high octane ethanol blend such as E25 or E30, then perhaps consumer demand for this fuel can serve as a bridge to future dedicated vehicles. Experiments were performed with four FFVs using a 10% ethanol fuel (E10) with 88 pump octane, and a market gasoline blended with ethanol to make a 30% by volume ethanol fuel (E30) with 94 pump octane. The research octane numbers were 92.4 for the E10 fuel and 100.7 for the E30 fuel. Two vehicles had gasoline direct injected (GDI) engines, and two featured port fuel injection (PFI). Significant wide open throttle (WOT) performance improvements were measured for three of the four FFVs, with one vehicle showing no change. Additionally, a conventional (non-FFV) vehicle with a small turbocharged direct-injected engine was tested with a regular grade of gasoline with no ethanol (E0) and a splash blend of this same fuel with 15% ethanol by volume (E15). RON was increased from 90.7 for the E0 to 97.8 for the E15 blend. Significant wide open throttle and thermal efficiency performance improvement was measured for this vehicle, which achieved near volumetric fuel economy parity on the aggressive US06 drive cycle, demonstrating the potential for improved fuel economy in forthcoming downsized, downsped engines with high-octane fuels.
Hier noch ein Link dazu:
https://info.ornl.gov/sites/publications/Files/Pub54888.pdf
Ich weiß nicht, ob ihr Zugriff dazu habt, aber bei mir hat der Link auch ohne Login über die Forschungsseite der HS funktioniert.
Hier die Zusammenfassung der Ergebnisse für einen Ford ECO-Boost Motor:
A non-flex fuel vehicle with a small turbocharged GDI engine was tested with an ethanol-free regular grade gasoline and a splash blend of this same fuel with 15% ethanol by volume. RON was increased from 90.7 for the E0 to 97.8 for the E15 blend. • Significant WOT performance improvement was measured for this vehicle. Using a fixedgear 30 to 90 mph acceleration time metric, a 1.0 second, or 5%, improvement was seen for the E15 fuel. • Thermal efficiency was improved using the E15 fuel on all test cycles, most significantly on the high-load US06 cycle. The US06 results showed a 4.6% thermal efficiency improvement with only 1% lower miles per gallon using the E15, despite a 5.6% lower energy density. A thermal efficiency improvement of 1-3% was observed on the lighter load FTP and HFET cycles. • No notable emissions changes were observed due to switching fuels. For the turbocharged GDI Fiesta vehicle with high-octane E15, the results on the US06 are indicative of what could be achieved with state-of-the-art downsized, downsped engines on the FTP and HFET. This engine technology represents a rapidly growing segment of new vehicle sales, and has significant potential for increased efficiency with high-octane fuels. Achieving within 1% of volumetric fuel economy parity on the US06 with E15 compared to E0 is representative of what could be expected in forthcoming vehicles with high octane E25 in comparison with more conventional vehicles using E10
Zum besseren Verständnis: 91 RON ~ 95 ROZ dementsprechend 97.8 RON ~102++ ROZ
Im Prinzip steht im Ergebnis allerdings nichts, das hier nicht schon unbelegt geschrieben wurde:
- Höhere Oktanzahl, niedrigere Energiedichte
- Bei gleicher Leistung - Potenzial zur Verbesserung der
thermischen Effizienz --> im Umkehrschluss: Bei Ausnutzung dieses Potenzials --> Mehrleistung
.....zur Arbeit fahre ich mit 3,6 Liter, zurück mit 4,0. Immer bei identischem Tempomat. Liegt an dem Streckenprofil (Steigungen etc...). 
