4age will give you from 10 to 12 km/l if you have soft foot & properly tuned. I will always recommend 4age for ke70. I have seen people with 3s,4efte, 3s beans in there ke70 but nothing beats 4age it fits well not so much of alteration is required good power with economy. Just remember to buy a good engine upgrade your breaks & get an LSD diff & you are all set.