Water pumps
 

I've been trying to do some research on interchangeable parts that are an upgrade to our motors for when I'm putting mine back together. For example I saw Marisa was planning to use an 11MM STi oil pump and upon research I found out our stock pump is actually one of two 12MM pumps, biggest they make.

Well last Sunday I helped a friend pull out his STi motor for the third time now, its been rebuilt 3 times and everything something goes wrong. We found out a wire pulled out of the back of an injector harness and one cylinder has never fired for how ever long its been rebuilt the last time, and found some crazy gouges in the cups and cams, the local Subaru tech advised to write the heads off as a total loss, he said enough is enough and ordred a stock motor and is parting out everything from the old one.

So I got access to a bunch of STi parts, most of it I can't use but one thing I wanted to try was the water pump. I've tried to look up some info on the different pumps or if theyre different at all but I haven't found anything yet. I was wondering if you guys knew if it was better or worse than we have or if it would fit? I plan to pick it up this week and give it a test fit, but I'm pretty sure my car didn't come with a stock water pump to compare it to (I know it wasn't on the motor, I doubt its laying on the floor boards). I can see if it bolts on but thats about it.