Hello Sourav,
Yes, there is a large difference except for one i.e both of the colleges are owned by one trust.
Bansilal Ramnath Agarwal charitable trust owns both the colleges. VIT is it's the main branch and is highly rated & autonomous. It is located in Bibewadi, Pune.
VIIT is its secondary autonomous branch. It is good, but less rated than VIT. This college is located in Kondhwa, Pune.
VIT ranking all over India as a private college was 5 in 2016. So, cutoffs are too high for VIT as compared to VIIT. But if you got VIIT, it is not a bad college it is autonomous and some staff comes from VIT too.
Hope this helps.
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