how to learn engine building???

[At-Least-It's-An-Evo]

It's not as hard as it may seem. If you know you did everything correctly and within specs, it will work. Take as long as you may need to do it, and just make sure it's right. I triple checked my own work and still kind of doubted it when I redid my engine(it was my first ever) and in the long run, I think it was well worth it. The second one may be coming up soon so we'll see how that goes. Good luck on your rebuild.