The KAUST CFR engine was modified to go deeper into the understanding of fuels. The use of a port fuel injector, instead of the usual carburetor, allows to investigate both Spark Ignition and Homogeneous Charge Compression Ignition combustion modes. The rest of the modifications allows to run experiments under wide ranges of intake pressure, intake temperature, equivalence ratio and dilution. Through that, the KAUST CFR engine pushes forward knowledge about autoignition and combustion processes, and also helps investigating the potential of new fuels and non-conventional mixtures.​