what armor set for condi engineer pre lvl 80?
The set you’re looking for is “Rampager” (PRE/cond/pow). Available at lvl60/lvl62 (blue/yellow)…
“Sinister” armor (same combination but with condition damage as main stat instead of precision) is available at lvl80 and not from randomly dropped stuff. (But with lvl80 you should better start to go for “Viper” (4-stat set with condition duration) (HoT required)).
I believe the proper answer is literally anything. Armor < 80 exotic is completely irrelevant. Just equip whatever green gear is on the TP that has better stats for some silvers, you should upgrade every 10th level (if you want to bother, sometimes you can wait until something drops or you get some level gear).