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does any one have the jabiru 3300 with the aerovee carb? i need to know if the carb throttle needs to be limited so it does not open fully? my engine runs rough at full throttle and i read on the aerovee that with some installations the throttle should be limited.

In my case, the EGT's all spiked at what I would guess to be the last 10% of throttle opening with no perceived power change (plus or minus).

I adjusted my throttle stop to stop before this point and have not touched it for eight years.

Thanks for the help, i would of thought a spike in egt would be fixed by enriching the mixture instead?

Kbellard wrote:Thanks for the help, i would of thought a spike in egt would be fixed by enriching the mixture instead?

I suppose it could...with a superbly modified needle at the exact right spot. I would think that it would require a profound notch in the needle. I wonder if it would add any power(?).

Your egt are high because fuel is too lean, its easy to turn your set screw 1/8 turn counter clock wise, and then take the block off your throttle. More power

Kbellard wrote:Your egt are high because fuel is too lean, its easy to turn your set screw 1/8 turn counter clock wise, and then take the block off your throttle. More power

If only it were that easy. Any adjustment will affect the other 90% of the throttle range which I am content with as is. I'll leave the "more power" on the table like many others have done at the expense of a fine running engine. The lean area is believed be caused by intake turbulence. If you can cancel that with 1/8 turn of the needle I will be surprised.

Kip is totally right in this regard. I also ran a Jabiru 3300 for 458hrs before switching to my Camit 3300 and now my total time is about 625 hrs.
My egt's go slightly high on #5 and #6 at wide open throttle. In my case I have no restriction limiting my travel so I instinctively go full throttle and come off the stop about 1/2". Shortly after establishing my climb, a quick glance at the egt's will tell me if I can do a bit more of come off the throttle a touch to keep the egts at no more than 1260 in full power climb. Sounds complicated but its not. It's about like glancing over at your prop RPM on a complex aircraft and setting it for its climb after takeoff.
The benefit of the extra travel comes in when your climbing at altitudes over about 7,000' DA. Then you can shove it full open because you can use all the air you can get at that altitude and higher.
Hope this helps explain the operation in a practical way?

Larry
Waiex121YX, Camit 3300, Skyview