Weber 34 ICH carbs

[GlennBurnage]

Might any of our members have any jetting/general info on Weber 34 ICH carbs used with a Bristol engine instead of the ususal Solex set-up? Any info gratefully received.

[Geoff Dowdle]

Glen,
There are at least three different versions of Weber 34 ICH carburettors.
Unlike the Solex that have removeable venturis the 34ICH venturi are fixed.
There are versions with 25mm , 27mm and 29mm fixed venturi .
Over many years I have fitted the 27mm version to 400 , 401, 403 , 405 and 406 .
I have heard that Bristol engined AC, Arnolt , Cooper , Frazer Nash and others fitted with Sports Engines use the 29mm version .

A standard 85 engine could be best fitted with 25mm versions.

Pls confirm the type of engine , compression , camshaft ,etc and I have the jettings that would be a good starting point .
The car would then need to be dyno tuned to check mxtures and ignition advance through the rev range .

Geoff