A8 1.2TDI is alive registered and running lean

[Vekke]

1997 Audi A8 1.2 TDI 6 speed manual Gas Mileage (A8 luxury fuel sipper) - EcoModder.com

Very good result in my first calculated "tank".
5.62 L/100 km
41.9 mpg (US)
50.27 mpg (Imp)
2.39 gal (US)/100 mi
804.38 Wh/mi

[kafer65]

Congratulations on this epic conversion! You always have interesting projects but the work involved is a testament to your ingenuity and tenacity. Would the Audi be about the same weight as your Passat now? I think the 1.2 TDI is about 250 pounds so did the car loose about 200 pounds after the conversion? I bet the handling is much better now.

[oldtamiyaphile]

Good to see this project up and running

I wonder if a 1.2 is actually too small and running high loads means richer AFR's?

[cRiPpLe_rOoStEr]

That's an epic project anyway.

[elhigh]

That's an awful lot of mass to tow around with a 1.2. I reckon once it gets up to speed it isn't too bad though. God knows the TDI engines make good torque for their size, if you have the time I don't doubt it'll accelerate up to highway speed eventually.

Have you done any aero mods to ease the engine's workload at cruising speed?

[UFO]

Originally Posted by oldtamiyaphile

Good to see this project up and running

I wonder if a 1.2 is actually too small and running high loads means richer AFR's?

Diesel engines do not regulate AFR, there is no throttle. As long as the turbo supplies enough air, the AFR will be lean under all load conditions.

[cRiPpLe_rOoStEr]

Well, nowadays that Ford uses a 2.8L turbodiesel in the Brazilian version of the F-350, let's give some credit to the 1.2L in Vekke's A8.

[kafer65]

Originally Posted by elhigh

That's an awful lot of mass to tow around with a 1.2. I reckon once it gets up to speed it isn't too bad though. God knows the TDI engines make good torque for their size, if you have the time I don't doubt it'll accelerate up to highway speed eventually.

Have you done any aero mods to ease the engine's workload at cruising speed?

He shows it weighing 1605 in his avatar info but I think he means 3500 pounds. Thats roughly my SUV's power/weight ratio. I have under 160hp/torque and he lists 120hp and 285NM which is about 211 ft/Lbs I think. He's getting that power around 1500 rpm and I have to rev my socks off to what I have. I don't think I've ever used more than 130 hp to merge onto the highway giving it the full beans according to scangauge. I don't think that Audi would seem sluggish. Heck, most of the time I'm using 20 hp to climb hills in town and less than that when I'm getting 40+ mpg. The Amarok truck uses the VW 2.0 with turbos to do 4x4 duty too.

[cRiPpLe_rOoStEr]

Originally Posted by kafer65

He shows it weighing 1605 in his avatar info but I think he means 3500 pounds. Thats roughly my SUV's power/weight ratio. I have under 160hp/torque and he lists 120hp and 285NM which is about 211 ft/Lbs I think.

Considering that it has a lower GVWR and is more aerodynamically-enhanced than many Euro and Jap vans from the 90's which had lower power and torque ratings, but still have a safe road performance, I would also assume it's going to be anything but sluggish.

[Vekke]

Second tank data are ready, so took some trip as weather was very warm in this summers scale on Finland +25 celsius in the evening and +17 on the night at the moment.

4.24 L/100 km
55.55 mpg (US)
66.66 mpg (Imp)
1.8 gal (US)/100 mi
606.69 Wh/mi

Had 50 km of traffic light driving in the beginning of the tank. Cam timing is now adjusted from -2.2 degrees to 0 degrees. That seemend to help quite much specially to low end torque.

Rest of the tank tried to drive 100 km/h avg speed as much as possible.

AVG temperature +22 celsius.

Measued odo trip error to be 1% so that is now corrected.

Speedo error is -6% which is also corrected for the avg speed.

Lot of black smoke is coming on bigger uphills so the ecu tuning is still way off before its fixed to this turbo and car. One driver opened his window on highway and warned that is my engine OK due to that smoke.

I would not say this is slow already at current state, even its not working perfectly yet .

Weight of the car is 1430kg at the moment plus driver which in my case is +100kg. With current level of fuel I would say under 1600 kg easily total in driving condition.