You can install the later rotors with no problems. As far as HP the Bosce pumps have the fuel screw inside under the square end cap. You can turn them up but you will have no way of knowing how far you are setting it. You could pull the pump off and have a pump shop adjust the fuel delivery to a TR96 spec. One thing to note, the same engine in the TR96 has the in-manifold air to water intercooler while the TR86 motor does not. So watch how hot you run it.