needle valve settings

[randoon]

I'm trying to run an OS 9B carb on a CMB .67 yellow head and I need to know a starting point for the needle valves. Thanks Randoon88

 

[153stars]

I'm not an expert but the magic number always seems to be about 2.5 out but small K&B carbs more 3.5 I read alot of posts on here about needles you can search posts will explain how a motor will bog then clear if you what to listen for.