ECU/Tuning. This will be different for everyone.- http://www.civic-eg.com/forum/viewtopic.php?t=2027
Now let's think, what ECU will be best for this setup? The answer is NONE. Most ecu's will run this motor, but run it pretty darn shitty. How could you even expect it to run right? This isn't a stock honda motor! You WILL need some way to tune if you want this thing to last threw the day, week, month, year.
If you're looking for an ECU, just get one that you can chip, and has vtec capability. That's it. FYI, generally, GSR ecu's run this setup like poop so steer away from them unless it's already chipped and ready to be tuned.
Also, don't just buy some "skunk2" or "Mugen" chip. First of all, it's highly doubtful it's an authentic program to begin with. Second of all, you're taking someone else's word for what program is on that chip to run your new motor. You MUST be retarded.
Every LSVTEC/B20vtec motor is different and must be tuned INDIVIDUALLY!
So, get an ecu. Have it chipped. Install a wideband O2 sensor. Hook everything up together. Run your software of choice, and tune. You will need to tune for 14.5-15.1 at idle, and then gradually increase that to 13:1 at WOT in vtec. This is just a general rule...but tends to be pretty close to a RULE in tuning.
Check out this thread that was posted in the B-block Forum. It talks about what you need to build a Reliable B20vtec or LSvtec.