Originally Posted by 00Dan
Does anyone have experience with the nozzle PN 47-862 that MSA developed for the Carbon Cub with the Titan 340? Per SB-22, it is a drop in replacement for 47-773 jet that is standard in the 10-3678-32.
I'm waiting to hear back from MSA on the nominal flow rate. The Carbon Cub users report good results but I can only find qualitative reports. I wonder if the results will be applicable to the faster RVs.
Per MSA the 47-862 nozzle is the same flow rate as the 47-773. I ordered and received the 862 nozzle earlier this week, it measured to #36 ID (same as the 773).
I flew it today and performed some lean tests. At 2500’ and WOT, #1 peaked first with full rich being approximately 110* from peak. At 8500’ and WOT #2 peaked first approximately 250* from full rich.
My previous nozzle (47-828) had some aeration holes for atomization, and at 8500’ showed approximately a 130* spread between richest and leanest cylinder. After I reamed it from #42 to #40, the spread was 170*. The new nozzle (47-862) had significantly more aeration holes from the factory and showed a spread of approximately 80*.
Further testing is needed but it seems the 47-862 nozzle has gotten me close to where I need to be, at the least. I’ll also note I did measure my float height when I had the carb apart and found it to be at the nominal value of 7/32”.