Piston creep and rebound are two non-ideal piston stopping behaviors in the rapid compression machine. Compared to nominal piston stopping, piston rebound/creep will result in a smaller/bigger 'adiabatic' core zone volume in the reaction chamber and length/shorten the ignition delay time measurements. However, the 'adiabatic core' hypothesis can still be validated under these compressions and ensures the applicability of zero-dimensional method in the model simulation. (C) 2020 The Combustion Institute. Published by Elsevier Inc. All rights reserved.