Ran into another problem though, which I can't seem to figure out. Since I still had steam getting stuck in the turbine, I figured I'm still producing too much, so I was gonna split it between 2 turbines. Well, went ahead and made a second line, split right after it's out from the boiler. No steam going through the second line. Thought it could maybe be because the first line still had the pressure (read: leftover steam) in it, while the new one didn't, so replaced the whole line. Now it only went through the new one? Well, maybe it's because the thing is shorter than the old... Made both of them same lenght, replaced the whole pipes, as well as the boiler and the grates, so there's absolutely no lefterover steam anywhere. Still only going through the new line.
So, is there any way to have 2 different outputs from the same boiler (and I've read about people running 2 turbines with 1 boiler, so I guess it is) and if so, how do you control the steam flow?
Steam getting "stuck" in a turbine is normal, it's how a turbine works. The turbine should be receiving a constant stream of steam or its output will constantly fluctuate, which is a bad thing. The grate shouldn't release more steam than one turbine can use, so you won't be wasting anything there.
Reactorcraft steam lines are very simple functionally, there isn't any kind of "network" they establish like RoC shafts or RF conduits or whatever. Boilers output to a pipe, which has an internal "tank", and when there's enough difference between the amount of steam in that pipe's tank and any adjacent tanks (other pipes, steam grates, or the HP turbine thing), steam pressure is balanced between that pipe and adjacent pipes/tanks. Since pipes are just individual entities interacting with one another, there should be absolutely no problem connecting all your boilers to the same line, then branching that line off as needed for turbines.
You can test your pipes with an angular transducer to see exactly how much steam they're holding. As one might imagine, if the amount of steam in the pipes is gradually increasing, you're using steam slower than it is being produced, and vice versa. As noted before, steam lines have an effectively infinite capacity, so don't worry about filling them up and having them burst or whatever. Also keep in mind you can toggle steam grates with redstone if you want to shut down your turbines and save the steam for later.
Oh, and make absolutely sure you're either voiding or reclaiming your steam. Letting it float off into the atmosphere causes
tons of block updates and will seriously impact server and client performance. To void it, place a block at the end of the turbine where the steam normally exits and instead of floating away it just gets deleted; this is technically a bug-turned-feature, which everyone agrees is useful enough Reika isn't planning to fix it. Otherwise, build a funnel and reclaim your steam with a condenser, repressurize it with a pressurizer and feed it back into your boilers; if you're only using normal water steam instead of ammonia, and you're not playing with finite water, I personally wouldn't bother with steam reclamation and just void it instead.