Why would someone chose to go with one vs the other and vice versa? Does one make more power? Is one more durable etc? I considering going 1.6 and I don't know exactly the difference between the two except one aligns by itself.

 

Go self aligning. You only have to pay a little more for guide plates, and have peace of mind. I will never again run SA rr's after my last incident

 

IMO non-self aligning is the only way to go... unless ofcourse someone was in the situation where their heads had press in studs, and/or they never planed on removing the heads from the car for machining......some people also don't want the expense of guideplates and a good set of hardened pushrods, which NSA rockers always require.......many (including myself)feel that having a strong stationary steel guideplate and a hardened pushrod taking care of the rockers alignment, is far exceeding having just a small stop or fence built into the rocker sides......some of which are just aluminum(if the rocker is)

 

So its cheaper to go SA? Why do most board members go with NSAs?

 

Safer, and more stable in higher RPM's.

 

the last part of my post are some of the reasons