Well, it seems to me like you are saying staying past the red line is gonna damage your engine or something, well engine damage isn't in LFS yet... So you don't have to worry about that!
Eventhough in the 2nd and 3rd paragraph you are seeming to say it's handicapped. If anything, to me the RAC seems faster, the FZ5 seems alot ..... snappier, and less sluggish, than in the last patch.