The AMF project called the Nova , has no relation to the P4 project (vrod) ,AMF at the time was in development with the water cooled Nova and had plans to make at least 3 engine sizes as you describe a vtwin and a V4 design,they also had the EVO in design and when HD bought the company back from AMF they made the choice to shelve the Nova and move foward with the EVO and the FLT line up,they are I think about 6 Nova bike at the HD musuem. The P4 project (Vrod)was started in the mid 90s,it was a direct engine concept taken from the the VR 1000 witch was a HD and Roush racing engine design partnership that started in the late 80s ,the VR 1000 HD/roush racing team entered in to the AMA circuit in the early 90s and I if I remember correctly they raced in the superbike class untill 2000 or 2001 before HD pulled the plug. but they already buy this time teamed up with Porche to develope the VR 1000 engine in to a streetable version called the Vrod