i dont no about the 115mph bit.ive had 125mph out of my 1.6 and it wasnt struggling.i think it could have done more and i do no the speedo does over read slightly.imo the 1.8,2.0 zetecs are cheaper to tune.hence the engine change over.i do like the 1.6 but they seem to be expensive to tune,im not interested in throttle bodys just forced induction only