Aero Injector Fine Tuning

[BRS]

Today I leaned out the aeroinjector by an 1/8th turn on the needle. Seemed to me that the last flight where I saw 8.5 gph was excessive. I'm learning. slowly but learning just the same. Upon take off the engine let me know it was a bit lean. It accelerated better and kept nice and cool the other day when I let it suck 8.5gph Rich/WOT.

Thing in, on a Lyc IO-360 if you asked me how much fuel should I flow on takeoff I'd tell you right off min 16 gph up to 19 gph depending on your build. I just don't have that info for the Revmaster R2300. But I'm pretty sure the numbe is at least 8 or 8.5 gph. This info early on would have been helpful.

There is a new (to me) feature in the 'Flight Data Viewer' the I used for the first time today. I probably should have known it was there but just discovered it. This may not be totally accurate as I've not yet calibrated my fuel flow inducer also I may have leaned after leveling off. Tomorrow, I'll have the fuel adjusted higher and will do this again. Here is a cool chart that it spit out...

[Bryan Cotton]

My lowly Aerovee burns between 4-5 GPH. 8.5 GPH seems stunningly high. How much HP does that remaster make?

[XenosN42]

Thanks Brock!

Keep in mind that a higher duration (listed in the 'seconds' column) will give you a more statistically accurate fuel flow rate. In other words the value for the range 2600-2699 RPM, which was flown for 231 seconds, should be more accurate than the range between 3100-3100RM, which was only flown for 49 seconds.

[BRS]

My lowly Aerovee burns between 4-5 GPH. 8.5 GPH seems stunningly high. How much HP does that remaster make?

200HP (just kidding)

Bryan, I'm with you and agree but...

At level cruise and leaned I seem to flow (like you) around 4.5-5gph. BTW - the Revmaster is rated 85HP@3200RPM. But likewise my IO-360 burns 10.5 ROP in cruise (or 7.5 LOP) but on takeoff it needs about 16gph. The extra fuel goes to things like cylinder cooling and detonation resistance.

In yesterday's flight, WOT on takeoff/climb I had trouble getting to full throttle without the engine faultering (expirence has shown this to be too lean a condition) and CHT's were a bit hot. This was flowing (according to the chart) around 7.3 gph. I'll duplicate the flight later today with a richer needle setting to verify.

It would be nice to hear from others who have a fuel transducer (red cube) as to what your max fuel flow shows up at in a steady state Vy climb at WOT/full-rich.

[Bryan Cotton]

Odd how different our experiences are. On climbout I've had some stumbles that I solved by leaning. I don't have a fuel flow transducer but I use 5GPH for climb on cross country planning.

[XenosN42]

Here are the values for my normally aspirated AeroVee. Airframe = OneX



Notes:
The values above 3100RPM are during WOT take off & climb. The mixture was full rich.
Values below 3100RPM were primarily during cruise flight and the mixture was leaned.

[Arjay]

Just curious. How do you achieve 3500 rpm out of a normally aspirated Aerovee?

Ron

[XenosN42]

Just curious. How do you achieve 3500 rpm out of a normally aspirated Aerovee?

Ron

Downhill?

In my aircraft the only way to get over 3400RPM will be in a descent. So in the example above I must have pushed forward for a few seconds at the top of a climb.

Once a tried to fly my OneX close to VNE. That test was flown WOT in a steep descent. I reached 194 MPH TAS but couldn’t go any faster because my RPM hit just above 3950. The max on the AeroVee is 4000. Your mileage may vary.

[Bryan Cotton]

I flew a little beyond Vne at less than full throttle, 3950 rpm, and a steep dive.

[BRS]

Thanks Michael,

That is revealing info.

You'r Aerove is flowing 7.44 gph @ ~3180 rpm
My Revmaster is flowing 7.76 gph @ ~3150 rpm ...
...(yesterday's flight) and it felt like a bit more would have been better.

The diffence is that the Revmaster is rated for 85hp @ 3200. That seems to be then, 0.09 gph per HP or almost 11 HP/gal. This is for max rich, max power, factoring in accelleration and cooling fuel. Just thinking out loud.

Any idea how many hp the aerovee puts out at 3200 rpm?