SonexBuilders.net

I am just about to order a 2200cc Engine from Jabiru. I would prefer to stick with the Bing Carb. Any reason not to, space etc??
Am I wasting my time trying to get the Jabiru Plenum chambers to fit??
Thanks
Phil

Hi Phil,

The Bing carb will work. When you go to fit the engine, remove the carb.. it will hang up on the mount and stop you from getting it on the pins.. ask me how I know!
You will probably need to manufacture a new cable mount plate to route the throttle and choke cables. Aux Fuel pump and carb heat provision.
Steve Woodham went Bing from the start, uses a Jabiru style airbox and filter. http://sonexaus.wikispaces.com/Steve%27s+Sonex+892
Stuart Trist (contact on Sonexaus) went back to a Bing from an aerocarb ages ago.
Others have gone Bing then aerocarb (Brian Heinmiller http://www.heinmiller.visionhost.info/)

Jabiru will send you the old style fibreglass plenums, as they don't believe the newer ones will fit under the cowl. They probably will with a bit of surgery. The old ones I received had perished plug grommets which fell off after a bit of handling! I ended up making my own metal ones as per Sonex type.
Lynn Jarvis's old build pages http://www.recreationalflying.com/tutorials/constructors/jarvisintro.html, he has a few pics of the old type plenums being fitted.

Also the Sonex exhaust they have will fit the cowl with the right exit angle BUT the exhaust pipes are too close together. Not sure if you could get them to place the pipes at the same angle but 40-50mm further apart that would help you a lot. Otherwise they can send a blank muffler with 2 or 1 pipe(s) for you to get welded in later.

Cheers
Tony

Thanks Tony
Jabiru sent me an order form part of which was a question what type of Plenum do I want. When I asked them the differences in height they replied back " you will be supplied the latest type because thats all we have". Anyway I have ordered a Zero hour solid lifter engine.
Phil
Sonex 759

Very nice Phil.. rebuilt solid lifter?
If you end up needing original plenums, I have a set.. :D

Yes Tony. Rebuilt Solid lifter

Hi Phill,
I think part of your answer is going to be based on 1) are you intending on running auto fuel or not 2) do you have any fuel line restrictions. There's been a ton of observations made on these subjects!!

I personally went back to a Bing on my Jab3300 powered Waiex even though I like the Aerocarb. I put the Aerocarb on it originally but was never able to get it to work completely to my satisfaction due to running auto fuel pretty much exclusively - and having an MGL Flowscan restriction in the fuel line. It wasn't the Aerocarbs fault, but my fuel type and equipment selection that caused the problem. After 130 flight hours of fiddling around with stuff, I finally put the Bing and stock mechanical fuel pump back on about 13 hours ago and really wish I would have left them on originally. It worked great immediately - took care of the issues I'd been experiencing before - and I've only changed jets twice tuning it(5 minutes each). I went with electric carb heat on it and a K&N air filter that Pete Krotje recommended. I didn't have to make a new throttle or choke mount, the ones that came with it worked just fine.

Personally, I'd start with the Bing (it's a known quantity and works), and spend your first flight hours working on other issues like tuning your CHT's and oil cooling system. I used the Sonex baffles and you do have to modify them slightly to get a balanced CHT cooling setup.

Lorin
Jab3300 with 145 hours and running strong...

Corby202 wrote:I am just about to order a 2200cc Engine from Jabiru. I would prefer to stick with the Bing Carb. Any reason not to, space etc??Phil

Hi Phil
I have a 3300 with a homemade copy of the Jabiru filter/heat box. Although its a very tight fit, it has worked without any issues. The only real changes to the Jabiru box are. The lid splits in two for removal and is more bulbous to help it work as a cobra head, and the airbox to naca duct junction, seen on the left of airbox. I doubt you will have any issues with the 2200 there is a ton of room behind them.

Corby202 wrote: Am I wasting my time trying to get the Jabiru Plenum chambers to fit??
Thanks
Phil

I'd say no. Initially I used the smaller jab plenums with external plug wires, they worked fine in the air, but if I had any delays on the ground the temps would exceed 150 c fairly quickly. I made some aluminium ones the same size as the sonex plenums, that got the ground temps under control. I see no reason the larger Jabiru plenums couldn't be made to fit. I doubt they are any larger than the sonex style. Fibreglass will also be more crack resistant.

Personally, other than being less work to install, I see no advantage in using the aerocarb. I get the same fuel burn with the bing. 19lph cruising at 130 kts.

Steve
Sonex 892 VH-ZSX

Here is the airbox. Its a bit rough, it was only meant to be a prototype.

Thanks for the information Guy's
Phil