[jtbo]

I put my summer tire set to this horrible thing now, Continental Viking Contact 5 winter tires with really low rolling resistance.

Instantly it did roll better, but could of been better, of course it was wet weather, but also tire pressures were only 2.4bar, so need to add a bit of those.

One rear brake seemed to bind tiny bit, tire rolled only about a turn when I give it speed with hand, but wheel seemed not to heat up. I need to evaluate effects of that and when weather is better might open brakes, it is just one of the most annoying jobs that I know of. I hate those springs in drum brakes...

If I aim to 3.5l/100km, that should not be too much to achieve, I believe.

edit:
I have been trough fuel logs and done bit of thinking, also put more tire pressure but that seemed not to make too much of effect.

For some reason weather affects a lot to my fuel consumption, wind and if it is wet, snow seem to kill fuel economy completely.

Also car seem not to slow down incredible fast, but it does not gain speed on downhill as well as before either, mostly what is different is one tire being normal summer tire and front lip is not on as well as spare wheel under the car is missing as it is that 4th wheel.

When driving on level ground car does go rather lightly, but it seem to need adding of throttle to smallest hills or it will stop middle of hill. However it seem to go as far with as little of speed decreasing when I coast down.

When I hit damp section on road it is like pushing brake slightly, car slows down clearly, but there still is no change in boost gauge, it reads more or less 0 on normal driving on level road.

So, maybe tires are causing lot higher amount of rolling resistance on wet road, I have read that around 15% is effect of wet road. Also I think that air going under the car is causing now a lot more drag and front lip had helped previously with that, also spare tire location might act as a parachute now, so it would need covering up.

Need to get car to MOT station and when that is done, I will need to start putting something together for aeromods department. Even mods don't seem to make much of difference when you put them on, taking them off is making car feeling like it would have handbrake on.

That front lip seem to have rather large effect at least, steep long hill where I now (with only lower grille block) get speed increase from 40kph to 80kph was with front lip 90-95kph and with mini kamm, wheel well covers, grille blocks and really low front lip 105-110kph, I guess it is around that much that mods can help.

I did try to do some coast down testing of cd and rolling resistance calculations, but it is really difficult to find level smooth road in here, almost every second on video there is loud BANG as there are rails across the road, also car is jumping up and down constantly and there is always downhill or uphill, oh and corners, 200m of straight is quite typical between corners, need to travel quite a bit to find some road that would be suitable for proper testing.
From numbers I managed to record I got CD of 0.247837426 and CRR of 0.018858425
Now I don't believe even a second that CD could be that, .35 I might believe is good salesman would say that, but .25 level is impossible. Sure car has aerial deletion and roof rack deletion, but it is station wagon.