white smoke is generally oil,for example mines doing it at the moment as the tuby seals are dying as for the "holding back" i dont know the ins and outs so hard to comment the low a/f ratio isnt uncommon (10.0) .toyota starlet turbos go as low as this from factory so cant be terrible. and yeah turbo tobz is right,i heard the same about these jam etc ecus,they like stock pressure apparently