I would like to get a boost controler for my evo8, my question is do I also have to buy a AFC or just the boost controler will be fine, I want to keep the boost up at 19-20psi all the way to redline, will this be safe with just the BC. My other mods are listed below and by the way the ECU flash I have runs 20psi to about 4k and drops to 17psi up in the rpm range.

 

19psi to red will be fine without a fuel controller, however adding a fuel controller will give you a much larger gain in the overall outcome. Be sure to use the proper octane and watch for boost creep and or spikes. Tuning is the key to making power.