A 1000 hp pump gas engine is way off the charts in terms of what engine builders usually build. I would say that your experience is exactly what I'd expect would happen if someone called up an engine builder and told them to build a 1000 hp pump gas engine.

Muscle Motors has a King Krate 622 that makes 915 hp on pump gas so they know how to build these things. Sounds like you pushed the envelope a bit by asking for 1000 hp. Anytime you push the boundary you have to accept the R&D aspect of the project. And R&D projects rarely stay on schedule or budget.