What transmission tunnel size gives the best options on engine/gearbox installations. Cortina diff (100 mm wider than book)

I believe you generally need to select your engine/gearbox combination and then build round it to make sure it fits.

What do you have available where you are?

I have been thinking 20V toyota with a 21R gearbox. The t50 being difficult to get.

The other option is the 16V turbo motor onto same gearbox.
The engine gearbox needs an adapter

I thought a generic size that would allow a wide range of known combinations might be a better solution.

[Edited on 26/3/07 by willemv]

the bigger gearboxes will eat into your pedal space, best to pick one and leave it what it needs, so keeping the max space for yourself.