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Mertz · 10-12-2009, 03:42 PM

I have turned out the APT 2.5 turns and it made a big difference. It no longer falls on it face but still has a bog between 35 and 45 mph. I adjusted the secondary air valve to 1/2 turn and it made a small difference. I reinstalled the AU secondary rods. I come off the line great and above 50 it accelerates great. It is just very sluggish at 35 to 45.

I also did a test with the accelerator pump disconnected and it ran about the same as with it. I also noticed some fuel at the top of the pump rod. I am going to change the pump. It must still be running rich if it doesn't need the pump to get off the line. The plugs are dark brown.

Lars Grimsrud has told me that with a modified carb there is no baseline to start from and I need an O2 sensor to get it right. I might have to get a bung put in so I can install a sensor.

10-12-2009, 03:42 PM	#12
Mertz Registered User Join Date: Aug 2007 Location: Reardan, WA Posts: 132	Re: Q-Jet conversion I have turned out the APT 2.5 turns and it made a big difference. It no longer falls on it face but still has a bog between 35 and 45 mph. I adjusted the secondary air valve to 1/2 turn and it made a small difference. I reinstalled the AU secondary rods. I come off the line great and above 50 it accelerates great. It is just very sluggish at 35 to 45. I also did a test with the accelerator pump disconnected and it ran about the same as with it. I also noticed some fuel at the top of the pump rod. I am going to change the pump. It must still be running rich if it doesn't need the pump to get off the line. The plugs are dark brown. Lars Grimsrud has told me that with a modified carb there is no baseline to start from and I need an O2 sensor to get it right. I might have to get a bung put in so I can install a sensor.