Following along!

TDI Update
 

For those that are interested.....

Here are some initial performance numbers from a flight a few days ago.

They are Max Continuous power (230HP =12.5gph), recommend cruise (185HP=10.0gph) and econ cruise(150HP=8.2gph). FF is (as I said before) difficult to read with a turbine meter system due to the engine lift pump is a mechanical piston pump pulling fuel at 66gph in flight. So these FF numbers were calculated using the factory information. I did develop a system that will read it pretty accurately but the computer that translates Marine language to Garmin has a problem right now. I'm not sure if it is worth the complexity and weight because fuel flow on this type engine is a fixed number related to the high pressure pump rack position.

The following was recorded from the GTN650 while flying on autopilot and letting speed stabilize for several minutes at each altitude/power setting. GW about 2600# on this flight

5000ft. Max 169Ktas Rec 160Ktas Econ 145Ktas
7500ft. Max 176Ktas Rec 162Ktas Econ 147Ktas
10000ft. Max 180Ktas Rec 169Ktas Econ 150Ktas
12500ft. Max 184Ktas Rec 177Ktas Econ 158Ktas

Engine is rated at 230HP to 10000Ft and drops off to about 170HP at 20000Ft (its max certified altitude). I don't have an oxygen system yet, so anything higher will come later.

Awesome project- very cool to see the bleeding edge stuff- thanks for posting!

Very interesting to see this! I missed it when you first posted it. Keep the information flowing, please!

Thanks for posting these numbers Scott. :)

I'm curious to learn about the "seat of the pants" experience. In the automotive world cars are rated on a scale for NVH - noise, vibration and harshness. How does this powerplant combination "feel" as compared to a typical Lycoming? How does it compare with respect to perceived noise and vibration levels? Are there any parts of the power band which just "feel" better?

When I look at those cruise numbers I'm thinking that's a lot of speed on not a lot of fuel. Yes, the RV10 is slippery to start with, but still, these numbers are compelling.

Looks like about 1 gph less than a 540 running LOP at similar altitudes/ speeds. The non-turbo 540 can't match the high altitude/ high power setting speeds of course.

First—-I haven’t spent any recent time in a four cylinder Lycoming or a six cylinder for that matter so…..

Initial idle can feel a little rough when the engine is cold at 800rpm (not terrible) and there is a band between 900 and 1000 that I avoid (only have 11 hrs on this one, but the TD 300 was similar), above that it seems pretty smooth to me. It runs at a constant 2200 rpm from takeoff till landing power reduction.

As for performance, the cowling I have is just what I was using with the TD300 and it was more oil temperature sensitive 235F in climb and around 205F in cruise. Both were with cowl flaps open year round. Initially, this one cools much better. Climb and cruise with cowl flaps closed is 195F and 185F. CHTs are not above 335F climb and 300F cruise with a 392F red line. So some aerodynamic improvements are in the works.

Great job keeping the project alive!

Remember that diesel fuel is about 10% heavier per gal, and has about 10% more energy per gal, than Avgas. Honestly, I thought it should do a little better than that.