Type 9 or Overdrive

[Joao Cantador]

Hello i own a transit 2.4L diesel, and i would like a little bit more speed from it..
So i was wondering which would be a better option, changing the 4 speed gearbox to a type 9, or fitting an overdrive to the old one?
I know that with the overdrive i would get a overall ration of 0.778:1, that would not happen with the type 9, but i don´t know if an overdrive is less reliable than the gearbox an i would spend to much time fixing it..
Can any one help?

Thanks

[DodgeRover]

Type 9's are generally considered weak in the transits, an overdrive would be a better option if you can get all the parts you need.

[Joao Cantador]

Thank you, that´s what i though

[Joao Cantador]

Just a few more questions, will i need a diferent crossmember to fit the overdrive, and a diferent driveshaft?
Thank you

[V184]

Yes & yes