need help, wont run above 3k rpm

[Ender]

What's the number on the ECU you're using? And what wiring harness are you using? Give us more details about the swap. Like is it a fresh rebuild? If so, what was done? Any porting work? Injector size/shape/color is important. You mentioned the rear plugs looked brand new, that would make me suspect the rear injectors aren't opening. Rotaries don't burn terribly clean, especially if they're not running right, so if they're clean I'd be at least suspicious. It's also possible you have a faulty TPS and or bad electrical grounds, those are common problems.