Zertroz

My friend and I have made a Voltz server and created a particle accelerator. When activating the particle accelerator, it raises to about 78% velocity and stays there. We checked and it is 30x32 blocks. We have enough energy, as its coming from 12 battery boxes that are being charged form a fusion reactor. We have tried anything we could think of and still nothing is changing. Any idea of whats happening?