Is it good to Load test with 3 node cluster at localhost?

If I create 3 nodes/instances of elastic search at localhost to create one cluster and perform load testing, will this give a idea that how many request my current topology will serve in the live environment where 3 nodes will be 3 different machines?

If yes then, how to create 3 instances of ES at localhost in ubuntu 14.04.

No because you have to deal with resource contention.