theyve been doing it for awhile... some even use the MIVEC ratios, FD and some even the whole gearbox.
end of the day, for FD it still comes down to the rest of the ratios too.... and honda is the gear ratio king... :D
plus... we not only have the 4.785FD, but we even have aftermarket 4.9 FD and if not mistaken 5.2 as well for B series....and thats still not inclusive of close gear ratios like ATS :P
i have a friend who has 4.4 FD with ATS 3,4,5 in his B16A EF... his 3,4,5 acceleration is practically the same with my stock 4.4 FD gearbox and stock B20 on a rolling start.....but top speed is at 190km/h coz of rev cut hahahahah