Hello dilipbhai,

If you are from Gujarat and your ACPC rank is within say 1000, you can easily get into any engineering branch of LD. According to current engineering trend, Computer followed by mechanical are generally first preference. So they are filled quickly.

Rank depends on 2 things, 60% of your Gujarat board average result and 40% of JEE mains.

But to answer your question vaguely, I would say 85-90% average and 140 around in JEE are enough. And more than that is always welcome :)