Disregard my last post, I must have been so tired that I didn't notice the vibration. Its still there. I replaced the harmonic balancer today hoping that would fix it but it didn't. The vibration just gets worse as the RPM's increase, its very mild under 2000 rpms, after that it becomes really noticeable. The motor mounts are the only other thing I can think of that could possibly cause this, any other ideas?