My brother is planning on doing a B20 frank on his CRX Si. So he wanted me to do it for him. He of course bought all the stuff needed and yesterday i began. I took the GSR head and inspected it, slap on some skunk cams, AEM gears, titanium retainers, new valves, etc. Next i decided to take a look at the block. THIS is where the PROBLEM began. i looked at the engine code. B20A5. i grabbed my brother off the couch, dragged him to the garage, and pointed it out. He said, "it is a b20" i'm like, YEAH! B20 OBDO prelude you dumb ass! so he took the motor back. this morning Venus Auto delivered the right motor. for you rookies, know your honda B,C,D,F,H,and K