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Jab 3300, wood 64x47 Zodiac 601 HD.
Recently rejetted from a .255 to .250 b/c I was running rich at high end.
Flew it for about 5-10 hrs with the .250 Main Jet in it, all was good, left bank was a little on the lean side and I was getting about 3100 rpm level at cruise on a good day.
Decided last night to try to remove the scat hose from intake and replace with smooth lined radiator hose 2 1/8" diameter, and nice smooth molded 90 degree bend from airbox.
I had expectations that I would get more power, and more even distribution of fuel, the exact opposite happened. One bank is now running even leaner, and much to my supprise I was lucky to get 2850 rpm today. I'm kind of bummed about this. What gives?
My thoughts are that now that I'm getting more air to the engine, maybe my mixture might actually be too lean. But the reality is I have one rich bank and one low bank with egts ranging from 1080-1150 on 1,3,5 to 13-1350 on 2,4,6. The average of them is about right, but there is a pretty big desparity. As a side note everything is very happy and even at cruise 2200-2500. The measurements I'm giving are MWOT, which is really where I want to dial it in and get the most pwr. It seems what I really need is better and more distribution of the fuel/air I am sending into the manifold, not necissarily more or less fuel.
So I've changed back to the .255 main. I did one high speed taxi like this but it was too windy to fly so I didn't get any good data.
WHAT ELSE COULD IT BE. Anyone else switch to a smooth intake hose and have to readjust?