sentences:  Nissan would also buy a Courage C52 chassis to run under their own team in order to have reliability in case the R391s suffered from mechanical gremlins, with the 1999 24 Hours of Le Mans being their first race with the C52.For the R391, Nissan would decide to use a new version of the VH engine, opting to no longer use turbocharging as they had on the VRH35L.Instead, a modified naturally aspirated version would be constructed, named the VRH50A.