----- Original Message ----- From: STEVE bennett Just a small note, the Rotec carb, is not a fuel injection system, nor fuel injector when compared to what a modern day automotive fuel injection system is. It is a knock off of the Ellison series of carburetors. Their web site does say " fuel injection", if you read down the page a bit. When Monnett came out with his AeroCarb, a POSA knock off, is killed the sales of the EFS-2, so Ben Ellison ceased production of that particular carb. Ellison Fluid Systems still manufacutrers all the other carbs. http://www.rotecradialengines.com/TBI/TBI.htm http://ellison-fluid-systems.com/injectors.shtml Steve Bennett ----------------------------
Good note Steve. Absolutely true. In the sense of today's modern fuel injection, or even the Lycoming/Continental style fuel injection, these are carburetors. They call themselves "Throttle body" injectors due to the lack of a venturi, so they are more resistant to carb ice, although they certainly can ice up. You'll note that Rotec considers carb heat to be manditory equipment. My hangar mate is using the Aerocarb on his 6 cyl Jabaru powered Sonex. They had a lot of trouble getting it tuned and working right, but it seems to work well since they finally figured it out. They have never had the plane below 5000' yet, so they may find some low altitude tuning issues when they do. The mixture on the Aerocarb doesn't seem to be very useful. About all I can say about it is that it is more friendly than a Stromberg NAS, but not as effective. And it is nowhere near as nice as a Marvel Schebler. The Rotec throttle body appears to be a knock off of the Ellison, but there is one important difference. These types of carbs are very sensitive to Gs, flow and air pressures. The Ellison has the pressure regulator built in as part of the throttle body. The Rotec has the regulator mounted separately, but there are restrictions on where you can mount it as posted below from the Rotec FAQs. Additionally, some testing I know about with the Rotec demonstrated that differing air pressures between the throttle body and the regulator created a bit of a disconnect in that the regulator and the throttle body weren't working together very well and required a pressure equilization hose to be run between them. >From the Rotec FAQ. - The remote fuel regulator can suffer from the effects of >G forces because these forces will alter the weight of the fuel in the >delivery lines. For this reason it is recommended to mount the TBI regulator >no further than 6 inches from the fuel fitting on the TBI?s main body, closer >would be even better. On the Horizontal plain the regulator must be mounted >level with the same fuel fitting or even slightly above +2? -00?. This is >important. Do not position the TBI regulator LOWER than the throttle body. -Jeff Scott Los Alamos, NM
