Performance Of CI Engine Research Articles

Assessment of performance and emission characteristics of CI engine using tyre pyrolysis oil and biodiesel blends by nano additives: An experimental study

In the current study, the diesel engine performance, emission, and combustion have been investigated using tyre pyrolysis oil (TPO) and biodiesel blended with nano-additives. The effect of the blending ratio on fuel combustion and emission was evaluated. The tyre pyrolysis oil was derived from scrap tyres through the pyrolysis process and biodiesel was synthesized from used cooking oil (UCO) through the transesterification process. Moringa oleifera-derived strontium oxide (SrO) nanoparticles were mixed into the fuel to provide extra oxygen for better combustion. Three blended fuels were formulated as: a) 5 % biodiesel and 95 % TPO containing 50 ppm SrO nanoparticles (B5TPO95SrO50), b) 10 % biodiesel and 90 % TPO containing 100 ppm SrO nanoparticles (B10TPO90SrO100), c) 50 % TPO and 50 % biodiesel without nano-additives (B50TPO50). Among the blended fuels, B10TPO90SrO100 showed the best brake thermal efficiency at 31.4 % and a brake-specific fuel consumption of 0.21 kg/kWh at full load. The B5TPO95SrO50 blended fuel showed reduced emission parameters such as unburned hydrocarbon (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) by 2.05 %, 8.30 %, and 18.00 %, respectively, as compared to the conventional diesel engine at an optimum engine load (27.9 Nm). Hence, waste tyre oil and UCO biodiesel blended with biogenic SrO nano additive can be considered a promising fuel for a sustainable environment.

Optimizing Biodiesel Yield and Investigating CI Engine Performance Using Biodiesel Blends of Pongamia, Animal Fat, and Waste Cooking Oils

Optimizing Biodiesel Yield and Investigating CI Engine Performance Using Biodiesel Blends of Pongamia, Animal Fat, and Waste Cooking Oils

Influence of banana peel waste biomass ratio in Co-pyrolysis of waste plastics to regulate aromatic content and oxygenated compounds: A study of liquid product characterization and its CI engine performance

We have reported the importance of biomass ratio in the co-pyrolysis of waste plastics to regulate the aromatic content and oxygenated compounds in hydrocarbon-rich fuels for enhancing engine performance. The study revealed that changing biomass to plastic ratio can control aromatic compositional change. The obtained product was characterized using different instrumentation techniques, such as NMR, FTIR, GCMS, etc., to identify the hydrocarbon types in the liquid product. Results revealed that it contains C8-C24 range carbon compounds with dominating aromatics compounds, as confirmed by 1H NMR and FTIR analysis. The pyro-oils contain different hydrocarbons: olefins, paraffin, aromatics, esters, and alcohols. It was observed that the presence of biomass in co-pyrolysis produces oxygenated compounds up to ∼12.08 % and also enhances calorific value up to 55.4 MJ/kg from 48.3 MJ/kg due to the presence of longer hydrocarbon chains of esters in pyro-oil. Biomass co-pyrolysis also improved the fuel properties such as pour point (<-25°C) and 4°C increment in flash point. Engine performance showed that blending biomass pyro-oil obtained from B25PS75 reduced fuel consumption and increased BTE.

Effect of different configurations of hybrid nano additives blended with biodiesel on CI engine performance and emissions

The use of nano additives to improve the cold properties of biodiesel is encouraged by its drawbacks and incompatibility in cold climate. Waste cooking oil (WCO) was transesterified to create biodiesel. A 20% by volume was used for combination of diesel and methyl ester. Current study aims to evaluate diesel engine emissions and performance. TiO2, alumina, and hybrid TiO2 + Al2O3 nanoparticles are added to WCO biodiesel mixture at 25 mg/liter. When B20 combined with nano materials such as TiO2, Al2O3, and hybrid nano, the highest declines in brake specific fuel consumption were 4, 6, and 11%, respectively. As compared to biodiesel blend, the largest gains in thermal efficiency were 4.5, 6.5, and 12.5%, respectively, at maximum engine output power. Introduction of TiO2, Al2O3, and hybrid nano particles to B20 at 100% load resulted in the highest decreases in HC concentrations up to 7, 13, and 20%, and the biggest reductions in CO emissions, up to 6, 12, and 16%. Largest increases in NOx concentrations at full load were about 7, 15, and 23% for B20 + 25TiO2, B20 + 25 Al2O3, and B20 + 25TiO2 + 25 Al2O3, respectively. Up to 8, 15, and 21% less smoke was released, correspondingly, which were the largest reductions. Recommended dosage of 25 ppm alumina and 25 ppm TiO2 achieved noticeable improvements in diesel engine performance, combustion and emissions about B20.

Investigation and prediction on emissions and performance of CI engine employing binary and ternary blends with Karanja oil, used cooking oil, and Dunaliella salina oil.

Massive consumption of fossil fuels and alarming environmental degradation are motivating researchers to learn about alternative fuels. Straight vegetable oils are an alternative to fossil fuels to meet the standards. Microalgae is also a viable carbon-neutral alternative to depleting conventional fuel sources, a solution to the industrial requirement of organic consumables and an option for a green and sustainable economy for biofuels. In the present study, lipid was extracted from Karanja seeds and Dunaliella salina biomass. These were used to prepare different binary and ternary fuel blends with conventional reference diesel fuel with different proportions along with used cooking oil with their concentrations ranging from 10 to 20% (v/v). The influence of these blends on performance and emissions characteristics in CI engines has delved at varying engine loads from 0 to 100%. The binary blend with Dunaliella salina oil has increased the performance characteristics while decreasing all the major emission parameters compared to reference diesel fuel and shows a significant improvement among binary blends. Ternary blends with Dunaliella salina oil, on the other hand, have improved performance while lowering emission parameters when compared to reference diesel fuel and demonstrate a substantial improvement across ternary blends. For predicting the performance and emission characteristics of binary and ternary blends, an artificial neural network-based model was developed. The optimum blends, OB6 (90% RDF, 10% DO) and OB8 (80% RDF, 10% DO, 10% UCO), improved BSFC by 10.71%, BTE by 14.23%, and reduced BSEC by 12.45% at full load. Emissions were generally reduced, with CO2 decreasing by up to 39.39%. The simulation results demonstrated that the created 4-7-7 model was capable of accurately predicting the performance and emission characteristics of various alternative fuel blends and indicating a stronger correlation between the predicted and observed values, having a high correlation coefficient of 0.9974. Binary and ternary blends with straight vegetable oils improved CI engine performance and pollutants compared to reference diesel fuel, indicating they have the potential to replace conventional fuels for sustainable development.

Modeling of CI engine performance and emission parameters using artificial neural network powered by catalytic co-pyrolytic renewable fuel

Emission and performance parameters of a 4-stroke CI engine operated on a blend of catalytic co-pyrolysis oil with pure diesel, produced through Azadirachta indica seed, waste LDPE (low-density polyethylene), and aluminium oxide (Al2O3) as a catalyst, are modelled in the current work using an Artificial Neural Network (ANN). At 500°C temperature, the highest oil output obtained was 93.91 wt%. The produced liquid fuel possessed similar physical features to that of pure diesel, including density (794 kg/m3) and heating value (44.42 MJ/kg), but lower flash and fire points that would assist in a better and complete combustion of the fuel blend resulting in a better performance and combustion characteristics. Using inputs including brake mean effective pressure, load, brake power, and torque, a developed ANN model was applied to forecast the performance (Brake Thermal Efficiency and Brake Specific Fuel Consumption) along with emission characteristics (Smoke and NOx). The Levenberg-Marquardt back-propagation training technique was applied for emissions and performance characteristics prediction having the best accuracy. Regression coefficients (R2) for predicting BTE, BSFC, NOx, and smoke were all very near to 1: 0.99801, 0.9983, 0.95753, and 0.97467. The study determines that the proposed alternative fuel could be utilized in blend with the pure diesel to in an unmodified diesel engine. It has also been found that artificial neural networks (ANN) could prove to be useful to model and forecast the performance or emissions of renewable fuels in diesel engines, with the potential for these fuels to be employed in transportation.

The effect of fusel oil and waste biodiesel fuel blends on a CI engine performance, emissions, and combustion characteristics

In this study, experimental engine tests were conducted to investigate the combustion, performance, and emission characteristics of a diesel engine using a fuel blend composed of diesel, biodiesel, and fusel oil. In the study, which was carried out by using fuels obtained from different wastes together in a diesel engine. Seven different fuels were prepared for experiments by adding waste cooking oil (30% and 50%) and fusel oil (5% and 10%) by volume to commercial diesel fuel. The tests were carried out on the Lombardini LDW 1003 engine, a three-cylinder diesel engine, at four different engine loads (10, 20, 30, and 40 Nm), and a constant speed (2000 rpm). The experimental results revealed that the use of WCO generally led to increased NOx emissions which generally decreased with the fusel oil addition to the fuel mixture. Considering diesel fuel as a reference at maximum load conditions, there was a 12.63% increase in NOx emissions with 50% WCO. A 2.45% decrease in NOx emissions was achieved by adding 10% fusel oil. Furthermore, HC emissions decreased with the addition of both fusel oil and WCO at all load levels. When diesel fuel is taken as a reference at maximum load conditions, a 90% reduction in HC emissions was achieved by adding 50% WCO, and a 50% reduction in HC emissions was achieved by adding 10% fusel oil. Additionally, when diesel fuel is taken as a reference at maximum load condition, it was observed that a 0.05% increase in the maximum cylinder pressure value with the addition of 50% WCO and a 2.09% increase in the maximum cylinder pressure value with the addition of 10% fusel oil.

Synergistic effect of hydrogen induction on the performance, combustion and emission phenomenon of dual-fuel CI engine with Chlorella vulgaris algae oil and its methyl ester

The present work aims to investigate the cumulative effect of hydrogen enrichment with the fuels of diesel, Neat chlorella vulgaris oil (NCVO), and Chlorella vulgaris methyl ester (CVME) in a mono-cylinder CI engine. The performance, combustion, and emission parameters of diesel, NCVO, and CVME are analyzed and compared to the findings obtained with hydrogen induction in the intake manifold under dual fuel configuration. With the effect of hydrogen infusion, the metrics of performance, combustion and emission parameters are improved. Under maximum load condition, the induction of hydrogen escalates the BTE from 32.74%, 28.01%, and 23.02%–35.39%, 31.40%, and 28.12% with diesel, CVME, and NCVO at maximal hydrogen share energy of 14.38%, 11.50% and 9.61% respectively. Alongside, the enrichment of hydrogen declines the carbon monoxide (CO) from 4.13, 10.38, and 19.24 g/kWh to 3.16, 8.02, and 15.26 g/kWh, unburned hydrocarbons (UHC) from 0.51, 0.71, and 2.02 g/kWh to 0.36, 0.50, and 1.64 g/kWh, smoke opacity from 55%, 75%, and 85%–43%, 67%, and 71% with diesel, CVME, and NCVO respectively. However, the hydrogen's significant flame velocity and immense calorific value confect to an elevated combustion temperature and subsequent rise in heat release rate (HRR) to, cylinder pressure, and emission of nitrogen oxide (NO). Among the tested fuels, diesel posses maximum HRR and cylinder pressure of 80.46 J/0CA and 88.67 bar respectively. Maximum specific NO emission was observed with CVME having 10.80 g/kWh, whereas diesel and NCVO has 9.49 g/kWh and 4.93 g/kWh respectively.

Using CRITIC-TOPSIS and python to examine the effect of 1-Hepatnol on the performance and emission characteristics of CRDI CI engine with split injection

Recently, biofuels with higher alcohol content have become a promising alternative to diesel fuel. These fuels are appealing because they are sustainable, renewable, and possess attractive fuel properties. This study uses a split injection strategy to analyze the performance and emissions of a CRDI diesel engine fueled by 1-heptanol. The work involved testing different fuel blends, ranging from 10 % to 30 %, while maintaining a constant engine speed of 1500 rpm and varying the operating load between 0 kg and 12 kg in 4 kg increments. During the second stage, the CRITIC-TOPSIS method determines the objective weights and rankings of various criteria and alternatives. A Python approach based on machine learning was used to ensure the CRITIC-TOPSIS results were accurate. Seven criteria were evaluated to maximize BTE while minimizing BSFC, NOx, smoke opacity, HC, CO, and CO2. The experimental results showed a slight drop of 2.98 % in BTE and an increase of about 13.33 % in BSFC. NOx and smoke opacity were reduced by 7.13%–4.53 %, while there was a 12.12 % increase in HC, 6.45 % higher CO, and a 5.5 % increase in CO2 at full load. Adding 1-heptanol to diesel and using a split injection strategy significantly reduced NOx and smoke opacity. The final ranking and best blend are determined using CRITIC-TOPSIS and Python algorithms to estimate performance and emissions criteria. At a load of 4 kg, D100 ranks first with a relative closeness value of 0.642, while at a pack of 8 kg, the blend HP20D80 ranks first with a relative closeness value of 0.633. According to the rankings, the HP20D80 blend is the best option for achieving optimal performance and reduced emissions in CRDI diesel engines. A research paper has presented a unique approach to multiple criteria decision-making (MCDM) validated using a Python algorithm. This method can assist decision-makers in making better-informed choices when faced with MCDM problems that involve various criteria and alternatives.

Allometry of nanoparticles in diesel-biodiesel blends for CI engine performance, combustion and emissions

Most countries in the world are facing two major challenges, one is the increase in the demand for energy consumption difficult to fulfill because of limited fossil fuel, and the second is the emission norms specified by many countries. Various methods are adopted to reduce emissions from engines but that leads to sacrificing the performance of CI engines. To eradicate this problem in the present study, the nanoparticles like (TiO2) are used with different particle sizes 10–30 nm, 30–50 nm and 50–70 nm induced in B20 (20% biodiesel and 80% diesel) with the constant volume fraction of 100 ppm, and utilized in the diesel engine without any modifications. The results showed that the incorporation of TiO2 nanoparticles improves the combustion of hydrocarbons and reduces the emissions of CO, unburned hydrocarbon concentration, NOx and soot. Moreover, among three sizes of the nanoparticles, those with size 30–50 nm showed interesting results with the reduction in brake-specific energy consumption, NOx, smoke and HC by 2.9%, 16.2%, 35% and 10%, respectively, com-pared to other blends used in the study, and hence the blend with the nanoparticle of size 30–50 nm is expected to be a more promising fuel for commercial application in CI engines.

The Effects of Dill Oil Biodiesel on CI Engine Emissions and Performance

The Effects of Dill Oil Biodiesel on CI Engine Emissions and Performance

Evaluation of CI Engine Performance Using Compression Ratio for Palm Oil Biodiesel

The experiment explores vegetable oils as potential future fuels for internal combustion engines, particularly compression ignition engines designed for diesel. However, these oils have distinct properties from diesel, requiring modifications for direct use. Integration approaches include adjusting oil properties or adapting engines. Commonly, transesterification aligns oil properties, but using biodiesel often affects engine performance. In this study palm oil biodiesel as a diesel substitute, evaluating engine performance and emissions. In a short-term test, engine performance and emission traits by employing biodiesel compression ratio of 12:1, 14:1 and 18:1 with diesel at full load. Findings indicated that 14:1 and 18:1 exhibited 1.01 % and 1.02 % higher brake power than pure diesel. Volumetric efficiency percentages were 82.33 for 14:1, 82.36 for 18:1, and 82.30 for 12:1. Notably, 14:1 and 18:1 showed 5.44% and 10.90 % increased brake thermal efficiency compared to diesel. Interestingly, 14:1 and 18:1 displayed 2.35 % and 2.61 % higher mechanical efficiency than diesel. The exhaust gas temperature was notably decreased in 12:1 to 18:1 compression ratio. Nitric oxide concentrations were 65.07 ppm for 12:1, 124.44 ppm for 14:1, and 126.48 ppm for 18:1. Carbon dioxide levels increased by 9.79 % for 14:1 and 62.47 % for 18:1 relative to diesel. Carbon monoxide concentrations were 0.07 % for 14:1 and 0.05% for 18:1, in contrast to diesel's 0.12%.

Feasibility Evaluation and Numerical Simulation of Diesel–Diethyl Ether–2–Methoxy Ethyl Ether Blends Fueling in Stationary CI Engine

In many developed economies, the diesel engine is very important for transportation and farming. There is a lot of research being done in the field of renewable energy to replace conventional energy sources because of the major environmental issues and the rising expense of diesel. Diesel engine cannot be reinstate because of its efficient performance at higher power and reliability with alternative engines. Diesel engine emissions are very harmful to the atmosphere and human health. The main contaminants in diesel engines are smoke and NOx, which need to be effectively monitored. A numerous research is going on to diminish the emissions from CI engines by using some additives as well as the use of alternative fuels. This experimental inquiry was conducted to identify a suitable addition to lower exhaust emissions and improve CI engine performance. The trials used various mix ratios of pure diesel and blends of diesel and diethyl ether-2-methoxy ethyl ether. Mixing of 5% DEE and 5% MXEE with 90% diesel on volume basis (D90–DEE5–MXEE5) showed optimum results of emission and performance. Low exhaust emissions (HC 63.15%, CO 60.00%, and Smoke 18.29%) found to be substantial at peak loads and performance increase (decreasing in BSFC 5.00% and increasing in BTE 3.00%) were compared to mixture D90-DEE5-MXEE5 with diesel (at standard engine conditions). However, NOx rises (2.60%).

Effects of Injection Pressure on Performance and Emission Characteristics of CI Engine using Waste Cooking Oil (WCO) Blend

For a long period of time, vegetable oil cannot be used directly in a direct injection diesel engine. The tolerance tests may indicate significant problems. The outcome of Injection Pressures (IP) on the performance and emissions of a diesel engine powered by waste cooking oil biodiesel were explored in this study. It is investigated and standard diesel results are compared to the performance characteristics and emission studies of a single cylinder, four-stroke, direct-injection diesel engine fueled with used cooking oil in 20% (on a mass basis) blends. This study established the appropriateness of using cooking oil. The experiment consisted of running at a constant speed of 1500 rpm and then loaded gradually. The tests were conducted at 5 different loading are 0%, 25%, 50%, 75%, and 100% of the load in kW, with compression ratios of 17.5:1. The result of adjusting the injection pressure to 185–235 bars with a gap of 25 bars, with the original IP set at 210 bar. Fuel injection pressure is critical in improving engine performance and emission characteristics. The diesel engine ran on Waste Cooking Oil (WCO) at various injection pressures, including 185 bars, 210 bars, and 235 bars. The engine tests were carried out to examine how a diesel engine operating on a WCO20 biodiesel blend performed and produced emissions at varied injection pressures. Except for NOx, biodiesel blends at 235 bars injection pressure performed better and had lower emissions than those at 185 bars injection pressure. Without any modifications, the optimal fuel blend can be considered for a compression ignition engine.

Experimental investigation of multi-additive fuel blend and its optimization for CI engine performance and emissions by the hybrid Taguchi- TOPSIS technique

In recent years, the critical stage of air pollution and government stringent emission norms like Bharat Standard VI in 2020 in India and Euro VI in European countries, along with the promotion of electric vehicles, has made the future of diesel vehicles unpredictable. The present work correlates and tries to overcome the emission issue by improving fuel properties using a novel multi-additive fuel blend which can control engine emission, mostly NOx, without compromising efficiency and operating fuel economy. Using experimental and literature studies, three additives were identified for creating a novel multi-additive fuel blend, viz. dimethyl carbonate, 2-ethylhexyl nitrate and ethyl acetate. Using the Taguchi Design of Experiment method, sixteen test samples having different combinations of these additive were identified for experimental trials to create sufficient and suitable test data for the optimization process. Technique for Order of Preference by Similarity to Ideal Solution is a Multi Criteria Decision Making optimization process, is performed to identify the optimized multi-additive fuel blend coded as D8EH6E4. Blending the optimized multi-additive sample D8EH6E4 with diesel fuel reduced NOx formation by an average of 19 % while causing a substantial drop in smoke at higher load conditions without adversely affecting engine performance and fuel economy.

Effect of Split and Re-Entrant Type Piston Bowl Geometry and Preheated Calophyllum Inophyllum Methyl Ester on the Conventional CI Engine Performance

Effect of Split and Re-Entrant Type Piston Bowl Geometry and Preheated Calophyllum Inophyllum Methyl Ester on the Conventional CI Engine Performance

Optimization of CI Engine Performance and Emissions Using Alcohol–Biodiesel Blends: A Regression Analysis Approach

This research paper investigates the optimum engine operating parameters, namely engine load, palm biodiesel, and ethanol percentage, by using a regression analysis approach. The study was conducted on a single-cylinder, four-stroke diesel engine at varying engine loads and constant speed. A general full factorial design was established using Minitab software (Version 17) for three different input factors with their varying levels. The test results based on the regression model are used to optimize the engine load and percentages of palm biodiesel and ethanol in diesel–biodiesel–ethanol ternary blends. The analysis of variance (ANOVA) revealed a significant effect on performance and emission parameters for all three factors at a 95% confidence level. From the regression study, optimum brake thermal efficiency (BTE), nitrogen oxide (NOx), carbon monoxide (CO), and unburnt hydrocarbon (UHC) emissions were found to be 12.57%, 436.2 ppm, 0.03 vol.%, and 79.2 ppm, respectively, at 43.43% engine load, 11.06% palm biodiesel, and 5% ethanol share. The findings of this study can be used to optimize engine performance and emission characteristics. The regression analysis approach presented in this study can be used as a tool for future research on optimizing engine performance and emission parameters.

Impact of Iron Oxide Nanoparticles Additives in Water Hyacinth/Diesel Biofuel Mixture on CI Engine Performance and Emissions

Impact of Iron Oxide Nanoparticles Additives in Water Hyacinth/Diesel Biofuel Mixture on CI Engine Performance and Emissions

Assessment of CI Engine Performance Utilizing Palm Oil Biodiesel Blend

Experiment was explores vegetable oils as potential future fuels for internal combustion engines, particularly compression ignition engines designed for diesel. However, these oils have distinct properties from diesel, requiring modifications for direct use. Integration approaches include adjusting oil properties or adapting engines. Commonly, transesterification aligns oil properties, but using biodiesel often affects engine performance. In this study palm oil biodiesel as a diesel substitute, evaluating engine performance and emissions. In a short-term test, engine performance and emission traits by employing biodiesel blends of 0, 20, and 50 % with diesel at full load. Findings indicated that B20 and B50 exhibited 2.40% and 3.88% lower brake power than pure diesel. Volumetric efficiency percentages were 82.44 for B20, 81.64 for B50, and 82.93 for diesel. Notably, B20 and B50 showed 9.35% and 10.70 % decreased brake thermal efficiency compared to diesel. Interestingly, B20 and B50 displayed 1.09 and 2.44 % higher mechanical efficiency than diesel. Exhaust gas temperature was notably elevated in B20 and B50 blends. Nitric oxide concentrations were 98.74 ppm for diesel, 105.48 ppm for B20, and 111.78 ppm for B50. Carbon dioxide levels decreased by 4.14% for B20 and 7.86% for B50 relative to diesel. Carbon monoxide concentrations were 0.082% for B20 and 0.080% for B50, in contrast to diesel's 0.10%.

Synergetic effect of liquid fuel derived from various waste feedstocks on performance, combustion and emission in a compression ignition engine

ABSTRACT Diesel engines being predominant in transportation sector are limited in addressing the sustainable development goals. The pressing need of environmental concern and fossil fuel depletion enforces the research community toward search of alternative fuels. In such context, waste materials have emerged as a promising feedstock for producing sustainable alternatives for diesel, given their abundance and their significance in waste management. Consequently, in this work, the waste feedstocks identified were waste plastics, waste lubrication oil, waste animal fat obtained from tanneries, waste cooking oil and waste tyres. For extraction of oil from these plastics, lube and tyre oil, pyrolysis was used and transesterification process was adopted for extraction of DLF from waste animal fat and waste cooking oil. The collected DLF was given for fuel property testing and found to be at par to utilize in a CI engine. It was then blended with diesel in the form of B80 (80% DLF and 20% diesel) and named as WTO B80, WLO B80, WCO B80, WPO B80 and WAF B80. To identify the differences in various parameters like combustion, performance and emission of CI engine at various engine loads, a bench test of a single-cylinder direct injection diesel engine without engine modification was done. The blend B80 of waste oil is analyzed in this work for its combustion characteristics and emission of various gases like nitrogen oxide (NO), carbon dioxide (CO2), carbon monoxide (CO), hydrocarbons (HC) and smoke. Among various liquid fuels tested, WPO B80 blend resulted in 32.81% BTE with NO emission of 1885ppm. The results also show emission of 67.2% of smoke, 0.18% of CO and 48 ppm of HC. The cylinder peak pressure for WPO B80 was at 72.85 bar and 48.04 J/deg CA peak heat was released, which concludes it as a suitable fuel for diesel engine compared to other fuels without any engine customization.