the bit you refure to is classed as the amal valve

this is a diagramme i knocked up years back for someone, hope it helps.








what sort of problems are you having?
your prob best to PM me as i dont come on here much, or if your a memeber of fiestaturbo.com, contact me on there as i use that all the time.
user name is the same on there, and as im a mod on there your find me easy