[ryans69chevy]

I'm trying to dial in my 4160 600 cfm 4 barrel carb on my 350 in my 67 c10. It's a list number of 1850-01.

When I bought it used it had 65 main jets with a 25 squirter and 6.5 power valve. It was very sluggish at a steady cruise going 25mph. It also was very hard to keep running on the road from a dead stop. I called Holley and they told me to up the jets two sizes. So I bought 67's. It made a pretty good improvement. It still was tough to keep running from dead stop. I bought a 31 squirter which seemed to help a bit, but same issue. I then bought a 35 squirter and 69 main jets. Still having same issues. Finally installed 71 main jets and kept my 35 squirter.

I've hooked up a vacuum gauge and I got my vacuum up to about 12.5. I set my curb idle screw and idle mixture screws. My spark plugs are telling me the engine is still running lean. I have 71 main jets and a 35 squirter. I have my accelerator pump shaft set correctly.

It still is tough to keep running when I slow way down and when I start from a dead stop or am cornerning. After I am cruising and floor it it runs pretty good. I know I need to up my jets another size or two, but am unsure on my immediate acceleration problem. Do I up the squirter another size? Or turn up my curb idle screw? I like it low so it doesn't drink my gas. 35 seems big enough since this came factory with a 31.

Holley tech told me I shouldn't need to upsize my accelerator pump cc's until you start needing a bigger squirter than a 41??

I have not messed with my carb cams I'm assuming they are stock...