Well so far the C-Spec without the pump is doing quite well. We will be getting more time on them hopefully today. But as of now, I am impressed with it. Only time will tell, but I suspect it will be a good engine with or without a pump. Besides that I have seen plenty of OS 91's that were not running a pump, that could 3D their ars's off. So I guess I am not completely convinced that the pump is absolutly needed. But that is just me.