I have a 1.8 zetec running GEMS ecu and twin 40's there is a flat spot from 1200 t0 1800 rpm not a problem if you on the power but can be a problem when toodling about. I have heard mention that ideally they need an additional progression hole. can any one enlighten me and send a diagram of what and where I need to be doingplease?

My zetec 45's have five progresion holes.

as far as I know its not a diy job I think webcon can do it by putting them in a jig.

A lot of places won't do it and as said it's not exactly a DIY job.........this guy did it himself....
http://www.alfabb.com/bb/forums/carburetors-fuel-injection/32856-weber-dcoe45-152-45dcoe-progression-circuit-modification.html

You can buy the 152G's 'G' standing for German spec I think. These have 4 progression holes.....some others come with 5 holes. Both not locost though!

Edit: The 152's are 45's.....don't know of extra progression holes for 40's

[Edited on 3/3/09 by SALAD]