TBFI anyone?

[cojaken]

I run an O320 in a 9A. Honestly the performance, economy, CHTs and EGTs are good, so why fix something that's working? Well the main motivation is simplification, if its available and I don't consider traditional fuel injection simplification although I think it offers more benefits than TBFI.

I haven't found many recent posts on Throttle Body Fuel Injection and as usual those that I have found are looking for help to optimize or address problems with their installation.

Is anyone "delighted" with their installation and would confidently recommend a particular brand for its function and customer support?

[Mark33]

When my buddy built his -7 he incorporated the Ellison TB from the get-go. He?s been flying his bird for about five years now and the Ellison has given him trouble free operations. The only little modification that he made to his fuel system was to incorporate a very small (1/8?) fuel return line and valve that when open purges out any hot fuel that could/would cause vapor lock. The return line is just plumed back to one of his tanks and the valve is just a simple manual on/off valve that he controls in the cockpit. The ability to purge the hot fuel out of the fuel system has made a HUGE difference and has completely eliminated any hint of vapor lock. He?s been extremely satisfied with his entire setup and the simplicity of the Ellison TB.

[cojaken]

Thank you Mark33, however, based on the otherwise deafening silence in response to my post, it seems TBFI is not a popular technology.

[Mark33]

Originally Posted by cojaken

Thank you Mark33, however, based on the otherwise deafening silence in response to my post, it seems TBFI is not a popular technology.

Yeah, I’m a little bit surprised that it’s not more popular than it is. It’s a really simple device and is made up of only a few parts. Due to its simplicity along with the great experience that my buddy has had with his, I was initially planning on going with one in my -7 project, but I ultimately decided to go with an electronic ignition and electronic fuel injection (EFII). If you’re trying to decide between a throttle body and carburetor, I wouldn’t let the lack of response from your inquiry deter you. I’d do a little bit more digging and research and make your decision from there. Good luck!

[KRviator]

Originally Posted by cojaken

I run an O320 in a 9A. Honestly the performance, economy, CHTs and EGTs are good, so why fix something that's working? Well the main motivation is simplification, if its available and I don't consider traditional fuel injection simplification although I think it offers more benefits than TBFI.

I haven't found many recent posts on Throttle Body Fuel Injection and as usual those that I have found are looking for help to optimize or address problems with their installation.

Is anyone "delighted" with their installation and would confidently recommend a particular brand for its function and customer support?

A bit late to the party, but I use a Rotec TBI 48/4 on my OX-340 and I'm "happy" with it, though I wouldn't say delighted. I had to resolve some vapour lock issues with it, and it flows more fuel than the original Rotec 40-4, but it starts almost instantly when cold using the plunger button, and instantly, and I do mean instantly when warm. First compression stroke and it's running after refuelling.

Would I do it again though? No, I wouldn't.

It is a good product, but next time I would go down the SDS EFII path. The ability to trim fuel to each cylinder coupled with the benefits of EFI, instant starting cold/hot, cold enrichment, better atomization, etc make it attractive, notwithstanding the extra $$. I had to remake the FAB due to the shorter vertical throttle body, it still requires carb heat (likely as an asre covering mechanism by Rotec, but they say install it so I installed it), I needed to tweak the mixture cable with a bellcrank and a few other minor things that don't give as much benefit as those same things would with EFI.

[Carl Froehlich]

I flew an RV with the Ellison TBI. My evaluation was it is better than a carburetor but not as good as standard fuel injection for how I fly.

Carl

[Robin8er]

I have a rotec tbi and I am less than pleased with it. Its finicky and rotec intends for you to fine tune it to your engine. This involves drilling out the spray bar carefully and then flying the airplane and also using an oxygen sensor to get the optimum performance. It performs very well on low end rpm, but does not like high speed or high power setting (both bad for RV's).

Save your money and dont buy a rotec tbi. I hate saying that because I really wanted it to work, but after hours and hours of testing/tuning and several phone calls to rotec I finally just gave up and bought a marvel carb. I havent installed it yet, but I am going to.

[rjcthree]

I?m flying 80 hours behind an Ellison in my -9A. The mixture balance is as good as the best carb story I?ve read, and I can get really lean with it before surging begins, leaner still to roughness. Easy starting hot and cold. It runs fat in the midrange. It tends to close the throttle over time if I don?t snug the friction lock. Plan for a drain out of the fab, mine will drip a couple of tablespoons on shutdown. I have pretty extensive shielding on my exhaust, have never had any vapor lock issues that I know of, but I do run the boost pump for ground ops. Happy enough, yes, but wouldn?t do it again.

I have a different opinion on EFI than most, but that?s thread drift.

[Mark33]

Originally Posted by rjcthree

.......I have a different opinion on EFI than most, but that?s thread drift.

Please elaborate on your thoughts/opinions about EFI/EFII...even if you?d like to start another thread.