Another Jetting Question

[Marc]

I recently changed out my needle from a CEK to a N3EG and I noticed that I have studder in the upper mid-range under hard acceleration. I pulled the plug and looks to be running a little rich. No real issue at low RPMs

Do you think that I need to raise the clip?

Here is what I got

Temp 45 degree F
Low humidity
elevation 500 - 1000 ft
Fuel 50:1 syn

Slide #7
Needle N3EG
Clip 3rd
Main 178
Pilot 42
Air Screw 1 1\4 turns out

Thanks in advance for your advice

 

[Jakobi]

What sized main and pilot did you have with the CEK? What clip position was the needle in? How did it run?

N3EG#2 will supply roughly the same amount of fuel as CEK#3 from 3/8 throttle to WOT both using the same sized main (according to JD jetting spreadsheet). If a fully clip position leans it off too far you could also try a N3CG#3 which is half a clip leaner.

 

[Marc]

Everything is the same as it was minus me changing the needle. I went out earlier and moved the clip however I get the same stud-er at about half throttle.

I will try installing the old clip and see if I get the same results

 

[Marc]

I cleaned up the carb again and put the CEK needle back. Double checked the float. I fired it up and its not studdering mid throttle. I plan on putting the N3EG back tomorrow and see if the symptom returns

Current set up

Slide #7
Needle CEK
Clip 3rd
Main 178
Pilot 42
Air Screw 1 3/4 turns out

 

[Jakobi]

Try the N3EG#2 and see how she feels.

 

[Marc]

put in the n3eg on the second clip on the stand it is running clean. I will take it out to the track this weekend.