Both are different colleges and private in ownership. Reva institute of technology and management was established in 2004 and Reva University in 2012. Out of both Reva Institute of technology and management  is rated as above average college for management studies and is rated AAA by Careers360.

So I would suggest out of both you should choose Reva Institute of technology and management.

Some of the recruiting companies which come in Reva Institute are:

Infosys
DELL
SAP
TCS
Wipro
LnT and more
Rest details you can check here .

Some of the recruiting companies which visit Reva University are:

JP Morgan
CisCo
SBI
ICIC
LnT and more

Check the list here .

The average package is approx 4-5 lakhs per annum.
Hope this helps you.

Good Luck!!