Malone makes no claims of improved fuel economy with common rail tuning unless that tuning includes the "econo" feature that can only accompany a DPF delete exhaust on the CBEA and CJAA cars that use fuel to regen. With deletes / Econo tune, FE increase can be as much as 10%.
I love how much more fun to drive a Malone Tuned common rail car is too. But if emissions are retained, don't expect to improve much on the already very good fuel economy the stock car gets. Even though the newer cars convert fuel into torque more efficiently than previous generation cars, You should not loose sight of the fact that VW has continued to make the cars bigger and heavier. There are physics envolved here that will prevent the fuel economy possible with the earlier cars.
