Nobody replied but I found some myself;
YOU CANNOT APPLY FOR OCI IN INDIA IF YOU GO THERE ON A TOURIST VISA.
https://mha.gov.in/PDF_Other/3OCIcardholder_FAQs_15112019.pdf
If you go there on a long term visa other than a tourist/missionary/mountaineering visa.
OR
who obtain their first Canadian passport in India, you may apply for OCI in India. For the very few who may qualify under this , read on;
1.
Cheaper to apply for OCI in India
* Passport surrender fee in Canada is CAD 250 . In India it is INR 5000
* OCI fees in Canada is CAD 425. In India it is INR 15000
2.
Processing time;
* In India, people report receiving cancelled passport the same or next day .
* In Canada, BLS takes about 7 days to return cancelled passport.
* In India, OCI process takes ( 8-12 wks) longer than Canada ( 5 wks)
* In Canada, OCI applications with BLS have become routine with many applying on a daily basis.
Not so in India. Plus there is verification by home visit by passport personnel in India.
.