I have a parameters on the builds as 

RunThisTest1=abc

RunThisTest2=def

RunThisTest3=ghi

TestCount=3

Invoke i=0..N builds setup is as follows

From: 1

To: $TestCount

Step: 1

Parameters: RunThisTest=${RunThisTest${TestCount}}

Need to run the build parameters replacement functionality twice to get the values with sub parameters replaced.