Inverted fuel system

[Rkfrv6]

I have a carbureted Lycoming O-320-A2D on an RV-6 and would like the ability to fly inverted with 1 negative G. Has anyone heard of an aerobatic carburetor that can be installed or is the only option to convert to FI?

[moosepileit]

Does a wing tank have an operable flop tube?

Either the Ellison or the Rotec TBI from Australia could work- though their airflow demands and other details do not make it a simple swap.

[Rkfrv6]

It does not. I have been considering a flop tube as well as inverted oil, but have read post saying you can get at least 20 seconds of inverted flight before running out of fuel with a fuel injected system. With the difficulties of switching to fuel injection, it got me wondering if there was such an item as an aerobatic carb on the market.

[Jpm757]

Stromberg PS5C Pressure Carb. will do the trick.

[moosepileit]

Had one on an S1S, it was dandy. Needs 15psi fuel pumps, mechanical and backup. I don't know, but suspect, the PS5 may be more tolerant of the FAB without many airflow mods, so changing the fuel pumps, though pricey, may make for a faster overall mod. The electric pump would be much larger than a Facet cube.

Does a PS5C have the same height and footprints as a MS carb? Vapor return also becomes an issue, so might as well actually add a flop tube pickup and inverted oil of same fashion.

The PS5 was plentiful on early Bonanzas and it was decent on many a Pitts, but have not seen many in the RV world.

[ronschreck]

Look into the Ellison throttle body injection system.

[Rkfrv6]

Thanks for the info. Does not look like the Stromberg pressure carb is available new anymore. Guess I will probably go with the Ellison EFS-4 fuel injectected system.