I am going with the CA18DET and s13 g/box as you well know they can put some HP. I am a FB and with a 12 gallon tank to help with rearward grip I think the S13 combo will be MEGA ....I am going the extra mile with a charge cooler, stage 2 chip, T28 and water/alky injection......boost will not be silly numbers probably not even double figures....should be interesting....Im sure some one else is going to use the CA18DET as well.....and there is a half built rb25det somewhere
.....thing is....you can change the engine anytime anyway even if it is a bit of hassle (ask Ash g)