How many hours to travel chennai to nellore by train or by road?

Chennai Central (MAS) to Nellore (NLR) 176 km; 2hr 41min
Jan Shatabdi (2077) (except Tue) Dep 07:00hrs Arr NLR 09:41hrs

Chennai Central (MAS) to Nellore (NLR) 176 km; 2hr 48min
Chennai - Howrah Mail (2840) Dep 23.35hrs Arr NLR 02:21hrs

Chennai Egmore (MS) to Nellore (NLR) 181 km; 3hr 11min
Tiruchi - Howrah Exp (2664) Dep 22:30 hrs Arr 01:41 hrs