spacecadet
Active member
Hi all,
I posted recently about my late model large log head having had its carb bolt pattern changed by a previous owner... I was able to resolve that and mount the Vintage Inlines Autolite/Holley 2v Adapter. Cool. I also purchased an Autolite 2100 1.02 (245 CFM) from Rockauto as the Carb.
Now, when I was researching which carb to use, I was considering a 2100 0.98 (190 CFM) from a 1962 Fairlane because it was closest to the original Autolite 1100. After reading about CFM and calculating a conservative value, I came to believe the Inline 200 is capable of around 250 CFM (maybe this is my mistake?)
Anyways- back to now, I have everything bolted up and the car fires up and idles smooth, drives nice cruising, but has a wicked stumble and some tailpipe backfiring just off idle. Everyone is telling me that means it's lean, so I've adjusted the accelerator pump to what I believe is it's max shot, but I can't change this off-idle "lean condition".
Photo of the pump setting:
Other details about the car:
-DUI Distributor and wires, new plugs. Pushing ~30 (or 32) degrees advance.
-New fuel pump/filters/hoses.
-Vacuum idle is 20, if I really juice the throttle is behaves nicely, doesn't appear to have any vacuum leaks.
I posted recently about my late model large log head having had its carb bolt pattern changed by a previous owner... I was able to resolve that and mount the Vintage Inlines Autolite/Holley 2v Adapter. Cool. I also purchased an Autolite 2100 1.02 (245 CFM) from Rockauto as the Carb.
Now, when I was researching which carb to use, I was considering a 2100 0.98 (190 CFM) from a 1962 Fairlane because it was closest to the original Autolite 1100. After reading about CFM and calculating a conservative value, I came to believe the Inline 200 is capable of around 250 CFM (maybe this is my mistake?)
Anyways- back to now, I have everything bolted up and the car fires up and idles smooth, drives nice cruising, but has a wicked stumble and some tailpipe backfiring just off idle. Everyone is telling me that means it's lean, so I've adjusted the accelerator pump to what I believe is it's max shot, but I can't change this off-idle "lean condition".
Photo of the pump setting:
Other details about the car:
-DUI Distributor and wires, new plugs. Pushing ~30 (or 32) degrees advance.
-New fuel pump/filters/hoses.
-Vacuum idle is 20, if I really juice the throttle is behaves nicely, doesn't appear to have any vacuum leaks.