Assuming, your a GEM (General-Engineer-Male), having a somewhat average academic record in 10th/12th/Graduation, you still have fair chances in securing a Call from Top 3 IIMs, ABC, provided, you have a significantly high CAT Percentile, atleast above 99.9. If not IIMA, securing a 99.9+ Percentile will surely lead you to Calls from some of the Other best 6 IIMs including IIM B, C, K, I, L, S and others.

One of my very close Seniors at a college, had a academic record of 88/80/6.27 CGPA in 10/12/Grad, secured a CAT Percentile of 99.91, and secured Interview Calls from IIM A and IIMC.

For more information and IIM Cutoffs do follow the link below

https://bschool.careers360.com/articles/cat-cutoff