Andy

CTR pistons won't fit, the B20 gets it's extra .2L of displacement from a larger bore, 84mm vs 81 I believe. The CTR pistons will have a 3mm undersized diameter piston and simply won't work. The only pistons you can use with a B20 block would be the stockers or aftermarket units. You might be better off just starting with a B18C1 and building from there rather than worrying about forcing everything to work together. If your really nuts for the 2.0L, a B18C1's sleeves can be removed and replaced with new stronger 84mm versions. It would basically build a B20 bottom end but with infinately stronger sleeves, all the B18C1's addition parts (oil squirters, crank girdle, higher pressure/volume oil pump ...) and probably more peace of mind.