Folks. A TB Does Not get larger when you optimize it.
A 60mm TB is still a 60mm TB after it has been optimized.
~Russell~
A 75mm TB!!!

WHY???
That's serious overkill. IMO even a 70mm TB is really overkill for any Duratec.
Yes the forced induction folks can get by with a larger TB because their air is being forced through it, not drawn through it.