Yowie wrote:
I wonder if this is caused by a feedback loop with the smaller turbo.
Eg the more ready boost of the TD04 comes in with mild engine load, the driver's foot eases back on the throttle because a load of boost isn't needed, torque map changes, turbo spools back down, mild engine load triggers rising boost, repeat.
Contrast with the bigger turbo that isn't nudging boost conditions at the same mild engine loads.
All things being equal, you'll probably save fuel with the VF52 because it's not trying to tip into boosted/rich all the time in normal driving.
I haven't noticed any change in driving style/throttle input between the two cars - at normal speeds with other cars on the road they behave identical, save for the additional smoothness of the 5EAT over the 4EAT. I've only got a single tank of fuel to go by, but I was nudging 390kms with a single bar left on the LCD screen. The fuel light wasn't on - I don't actually know what happens on the S-Edition cluster when it gets low. The economy was 11.2 IIRC and was practically all suburban driving with a quick dash on the Centenary Hwy. The XTP has averaged anywhere between 10.4 to 11.6L/100kms depending on where we drive it. We would fill that up on the fuel light most times, having travelled anywhere between 380-420kms. It's pretty poor economy but better than the 17L+ I was getting in the STi on e85, considering I had to use 20% of my tank capacity to get fuel and get home again... leaving me with 180kms worth of fun before I had to do the fuel run again haha.