Need a good Dyno/tune company near chicago

a buddy of mine got screwed by a place in down town joliet. they had his car (firebird) for 6 months and gave it back to him running on 6 cylinders and gave him a dyno sheet that read 170HP.
hes got a few mismatched parts and such but it should definately be putting out a lot more than it is.
so i need a recomedation of a good tuner near joliet/chicago.

thanks