Aircraft Efficiency: Bristol Britannia-Twin Engine?

John questioned:

May maybe a Bristol Brattania be converted to a twin engine for fuel efficiency? Here is what I had in mind:

1. It is already one of the more flourishing and efficient crafts each bent (like those abstruse wings). I infer this would also work on the Electra.
2. Each engine had about 4,000 SHP (16,000 collective total)
3. Exchange those 4 with two of the Europrop TP400′s (down rated to 9,000 shp from 11,000; this will give max. potential at privileged alt.) for a collective total of 17,000 SHP.
4. Convert the props to contra rotating props. This will allocate shorter slower turning props and therefore slower tip speed for cool down surgical course of action.

It seems to me this must offer akin normal, maybe vaguely improved with new prop equipment, even stuck-up array, and a lower seat cost.