I had an 3T engine and tuned it up to fast but noticed one thing. The rod was an R2 and could not handle the faster specs.
I do not know what the 5T is using but if it is an R2-R4 it is wise to change it quickly to a R7. And I know someone who is giving these engines the specs of a Flash and they do run very good.
Speed is only fiction but a 130+km/h MRS4 is for real.