I am playing around with twin HD8 carbs. I have them on a turbo charged 179 Holden motor.
My question is about the slow idle screw. Does the slow idle screw effect the air, or the fuel when you screw it in or out??
This info will help me greatly. Thank you

 

The HD series carbs are an "air bleed" idle adjust.

So the more IN is slower, and vice versa.

 

Thanks mate.
Much appreciated!
My engine is rich as on idle, it burns your eyes
Then after about 20 to 30 seconds it stops and spits fuel and air out of the carbs.
So I have play with differant needles to I think.
That's a great start for me, thanks