luckily for you, i ahve nothing better to do at the moment than look up odd tidbits
http://www.goodman-games.com/forums/vie ... c&start=89
As for stacking a boiler with it, yes, the intent behind the steam power rules is to do cool things like that, so sure! But your DM has the final say, especially when it comes to something that could massively multiply your PC's Strength! I'd say each boiler applied to hydraulic armor would grant an effective +2 to Strength, or something along those lines. Boilers are supposed to be the kind of item that start off weak (because they double things that start at low numbers) but end up strong (because eventually 2 to the Nth power gets pretty big) so a +2 Str bonus would allow the hydraulic armor to slowly get more powerful.