So, I had this mostly working with 4.8 but with the replacement of some nodes in 4.9 made my BP mostly broken. I didn’t want to be restricted to 4.8 (or from future updates) so I was determined to fix this issue. After looking at the same year old video tutorials and other examples around the unreal engine I couldn’t figure out how to fix this problem, because everyone seems to have it. The Epic racetrack BP can’t do loops and neither can all the other BP’s I found out in the wild.
So I just tried to simplify my whole BP and start experimenting. I do believe I found a solution that isn’t too wild… just about every attempted solution I saw for this was trying to get the Spline’s Up Vector in some capacity, altering/rotating the vector around an axis by some degrees, and then Setting the Up Vector to the mesh again. I found that, since 4.9, to be completely impossible (hope to be proven wrong). So instead, I got the Spline’s Right Vector, which apparently lacks any of the baggage of the Up Vector’s turning, and used that to set the Spline Up Dir. The only thing I had to change the default orientation of the mesh I was using to compensate for the different axis.