Observed bolometric LC (top panel) and Fe IIλ5169 line velocities of SN 2006ai (black markers). Solid lines represent the high-M_ZAMS models with increased mass loss that best reproduce the observations. Dashed lines represent the maximum a posteriori model using our standard grid of models. This model is corrected by the scale factor and the explosion epoch found in Sect. 5. Since our estimation suggests an earlier explosion epoch, the model shown as dashed lines starts before zero on the x axis (where zero corresponds to the explosion epoch derived by Gutiérrez et al. 2017b).