The Madras (MAS)-Bangalore (SBC) route by BG was 358 km.
But it was also possible to travel between Madras Egmore and Bangalore City entirely by metre gauge at that time. Here is the distance table for the stations:
This was entirely within SR. Unlike the BG route, it did not touch Andhra Pradesh.
1 possible set of trains would be:
Madras Egmore: Leave 08.10 by 137 Madras-Quilon Express
Vriddhachalam: Arrive 13.05 by 137, depart 19.15 by 130 Tiruppapuliyur-SBC Fast Pass
Bangalore City: Arrive 06.40 by 130
This takes a little less than 23 hours. Further fine-tuning may be possible.
At this time, the BG trains such as the 7/8 Mails took 8 hours. The fastest was the 39/40 Brindavan Express which took 5-6 hours, and the 23/24 Express took 6-7 hours.
abn397 
Interesting observations, Ajai. After more than four decades, Brindavan Express now takes 6 hours 20 minutes. Shatabdi Express takes almost 5 hours. Not much to boast of really, for a Railwayman like me.
Have a safe and happy New Year.
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Electrification hasn’t helped !
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