^^ The current road expansion from podanur to chettipalayam will be extended till palladam and pollachi.
I think no. Or it should not considered like that even if Kochi-OK Mandapam-Palladam is 4-Laned in distant future.
Podanur-Chettipalayam is a small stretch which may become part of Podanur-Pollachi new road.
Pollachi-Palladam is altogether a different stretch now being widened to 4-lane road.
In near future, Pollachi-Sultanpet (of Palladam stretch) - Somanur will become a 4 lane road.
An update to my post.
Kochi-Palladam road in fact passes through Chettipalayam. But it is not a major road between Velanthavalam to Othakalmandapam. From Chettipalayam (or Othakalmandapam) to Palladam it is SH163. (from Google).
Even then, Kochi-Palladam road may not require a 4 lane road in near future as it does not connect big towns nearby.
OTOH, CBE-Podanur-Chettipalayam-Kondampatty-Pollachi new road may immediately become a main road due to the reasons already posted in this thread and as it connects CBE and POY.
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Regarding how I thought of Pollachi-Sultanpet-Somanur 4 lane road is can be seen in the map. Actually, years back I have posted in CBE road projects thread about widening of this road (from Kamanaickenpalayam to Somanur) for future. It is SH165 about 23 km. Advantage is it is for the most part a wide 2 lane road except between Kamanaikenpalayam to Karadivavi which is a small 2 lane road.
I think, road widening work is on-going between Karanampettai and Somanur or even from Karadivavi to Somanur. I am not sure. Some member can confirm it.
This Kamanaikenpalayam is located on Pollachi-Palladam road near Sultanpet.
Once the SH165 is 4 laned, then vehicles from Chennai/Bengaluru/Salem etc to Pollachi or even Udumalpet and Palani can use this road. May be to Kerala too, via Pollachi and Udumalpet.