I have a 1991 civic dx with the d15b2 motor and I'm looking to do some semi-budget upgrades. Its my daily driver but wantt a little more get up and go. I did an obd0 mpfi swap over the summer. Now im thinking about rebuilding the motor. I was gonna upgrade the valve train with a d16a6 camshaft and a supertech valve train kit. I was also thinking about putting in some better piston rods and possibly oversized pistons maybe but I'm not really sure if thats worth the investment or not? If i were to do all that would i need to upgrade to obd1 or 2. And which ecu would i use?