400bhp is a monster Bro! I hope it's whp and not crank hp. Will probably look up this workshop.
I've come accross the following but wouldn't know about pricing:
1. Obermaier, Jln Ipoh - Installed DCI and Vishnu - RM450 after requesting discount (hehe..) Parts i bought it myself
2. Raymond Auto, Kota D'sara - Recommended by Marco, Motorsport Division
3. Auto Mobile Garage, PJ opposite ColdStorage Jaya One - Normal servicing only.