I have a Speedmaster 8 stack and I'm having problems with the idle, as it's around 1,500. I put a return spring on it with no effect.
Is there a idle set screw ?
I can help you out. I have set up numerous 8 stacks. Have you synced the stacks? What ecu are you running? Post a picture of your system they've made some changes over the years. Where are you located?