Hmmm... I may be out of my league here, but here goes.
I have read both threads on this topic. While I AM new to Subaru, I am not new to the automotive industry.
First, there are many problems with engine/drivtrain swaps. Even swaping a larger engine from the same manufacturer can have a huge share of problems. Then adding to that, fabricating to fit something that was not intended, plus a heavier load on suspension and body/frame, then add the stress of off road (I assume that is the intent of use with this vehicle)... well it has been done, and very successfully by the pros who have a lot of time and money to do it many times over just to get it right.
If you have a lot of time and money to work at this, and want lots of horse power/torque, look at the the larger V-6 engines, like GM's 4.3 or Ford's 4.0 liter. Plus a whole new drive train to go with it, then all new suspension. This project could get rather pricey.
If you are like most people who aren't tied into a bank account that seems to have no end (and I think this would fit you more accurately due to the base vehicle you are working with), my suggestion would be to try the simpler swaps of the larger Subaru engines that produce ad admireable amount of power/torque.
Hey, I'll be honest here. I am intersted in the Subaru's because of the power/torque they produce out of the small package. I am looking at a 300+ hp 1974 VW Karman Ghia Street Rod. Something that would take considerably more work, money, time and have far less reliability if I built a VW based engine (which I am familiar with) to do the same job.
My hat is off to you when ventures are taken in this area. Just try to make an educated decision, a well thought out decision, before delving into something that you may loose a lot of time and money on only to find you do not have the resources to make the end results satifactory.
Good luck!
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