B-Model test flight posted

[vwglenn]

But...Chubby? Really??

I don't see it either Joe. If anything it looks sort of shark-like. The wider nose reminds me of a shovel head when you compare it to the original. I dig it.

[mike.smith]

But, after doing research, I moved the cube location and then removed some of the flexible line and fitted with AN fittings from the firewall to the fuel filter (cube in between) and have found it to be extremely reliable and accurate. I have done measure testing and its within .05 gph over 2 hours.

I conversed with the company. I showed them my setup and they could not find any issues with the way it was plumbed (all fittings are AN-6):
- Fuel tank
- Finger strainer
- Braided fuel line to firewall
- Firewall fitting
- Fuel filter
- Gold Cube
- Short section of braided hose
- AeroInjector

They didn't have any ideas other than to possibly remove the fuel filter, which is not something I want to do. So I'm open to suggestions.

[jjbardell]

Mike,
I'll get you pics of my setup. I believe your issue may be that it's a gold cube. The flow volume and accuracy are for a much higher rated flow rate. The red cube is for lower flow rates. Although the red is stated for fuel injected, it is actually the better suited for our planes.

Red cube - 0-350hp w/ 0.6-70 gph
Gold cube - 350-500+hp w/ 3-125 gph

Someone can prove me wrong, but Matt at MGL and I both agree the gold cube will not be accurate due to the pressure drops and flow requirements. It doesn't even read below 3gph and the transducer turbine cant spin properly to get a reading with our low volume of 1gph (taxi) to 8 gph (40" fully loaded climb).

Also, I recommend filter to be after the red cube, not before. There are two reasons for this I can share if you wish.

Not seeing your layout, you also need to be sure to have the cube at a 2-5 degree downward angle so air doesn't get trapped in it. Your line after you exit the firewall needs to flow downhill all the way to the aero injector.

The cube should follow that path.

Also, make sure it is setup as "turbine" in the mgl setup menu. It's a turbine impeller. Some think it means turbine aircraft. Then set the K factor. I believe it's 18000 for the red cube.

Send me a pm if you want to FT, call or want pics of my setup.

[mike.smith]

Mike,
I'll get you pics of my setup. I believe your issue may be that it's a gold cube. The flow volume and accuracy are for a much higher rated flow rate. The red cube is for lower flow rates. Although the red is stated for fuel injected, it is actually the better suited for our planes.

Red cube - 0-350hp w/ 0.6-70 gph
Gold cube - 350-500+hp w/ 3-125 gph

Someone can prove me wrong, but Matt at MGL and I both agree the gold cube will not be accurate due to the pressure drops and flow requirements. It doesn't even read below 3gph and the transducer turbine cant spin properly to get a reading with our low volume of 1gph (taxi) to 8 gph (40" fully loaded climb).

Also, I recommend filter to be after the red cube, not before. There are two reasons for this I can share if you wish.

Not seeing your layout, you also need to be sure to have the cube at a 2-5 degree downward angle so air doesn't get trapped in it. Your line after you exit the firewall needs to flow downhill all the way to the aero injector.

The cube should follow that path.

Also, make sure it is setup as "turbine" in the mgl setup menu. It's a turbine impeller. Some think it means turbine aircraft. Then set the K factor. I believe it's 18000 for the red cube.

Send me a pm if you want to FT, call or want pics of my setup.

I called the company before and after, and they SWEAR the Gold Cube is the one to use for gravity feed systems, and the Red Cube is for fuel pumps. I didn't believe it either, but they've told me twice, now. They are standing firm to that premise and will not make an exchange.

My fuel system does go downhill all the way to the AeroInjector. I can try putting the fuel filter after the cube. I'll check the "turbine" setting next time I'm at the plane.

I got your PM. I'll send you my email and would be happy to have a look at your setup.

[DCASonex]

Red cube has been very accurate for me from the get-go. Last thing in system before the Bing carb, but with long aluminum tube running halfway across the firewall, 180 degree bend then back again to the red cube,

David A. Sonex`TD, CAMit 3300

[mike.smith]

Here was the company's response:

The fluctuating readings are almost certainly not due to the FT-90 (Gold Cube) being installed instead of the FT-60 (Red Cube). The FT-90 is most often supplied in gravity fed systems, including engines such as the 0-200 which sips fuel at an average of 5-6GPH in cruise. As Tyler mentioned in an earlier e-mail, the FT-90 is the preferred transducer in gravity fed applications due to lower pressure drop. Worth noting, fuel flow is not a linear measurement. What that means is, 1/2 throttle will not give you exactly 1/2 full throttle fuel burn. The K-Factor should be programmed per the most common flight condition. Typically, that is going to be cruise configuration.

[LarryEWaiex121]

Michael and gang,

Not trying to bust into the Turbo world with my Camit talk but I have some interesting comparisons.
My Waiex with the Camit runs 138 mph averaging runs both ways at 2750 rpm and 3,500'. Fuel burn comes in precisely at 5.4 gph.
Step it up to 8,500' and 2850 rpm and averaging runs, it comes out to 151 mph. Fuel burn once again will come in precisely 5.4 gph.
I think what a lot of this points out is it takes exactly X amount of power to go X fast in this design plane. You can either get that power by turboing a smaller C.I. engine or a bigger displacement engine but they both burn roughly the same fuel for each H.P. generated.
I understand I'm generalizing here, but I believe its pretty close?

Larry
Waiex121YX, Camit 3300, Skyview