pretty good information... with your research, perhaps you have this info and i'm too lazy to look
1. What is the CR of this engine? Does it differ between 25,28,30?
2. What is the material the crank is made from? forged (not if i recall)
3. Connecting rod material? shape (structure, ie. I-beam..etc)
4. Head gasket material?
5. Head bolt strength? (can easily be resolved, but important)