Sorry but I confused the fact that we are talking about a
5 speed here instead of a 4 speed.   In the 4 speeds 3rd
gear ratio is a 1.23 and in the 5 speeds 4th is a 1.01.  I
had some misgivings about the jump between a 1.23 3rd
a .70 4th but can see now that it isn't as 'large' as I thought
with the 1.01 4th to the new .70 5th.

Look forward to hearing about your engine!

-Todd Hill
 VolksWerks Transaxles
 Olympia, WA