Throttle issues

[Agb]

Hi. I have a 1967 912 for over 5 years with Weber idf 40s and never been happy with the idle speed. It seams to fluctuate a lot ,after year of checking , adjusting and changing parts . And even wasting money on auto performance places with on success.
A question has any one fitted a different type of throttle control/linkage to a 912 or 356?
I was thing of going to a split cable type set up ?
Regards. Andew

[Steve F]

You need to all of it adjusted properly, follow these instructions and it will work

[WFBowen]

In addition to being absolutely certain that your linkage is not the problem (binding) check your distributor rotor for a clean snap back when you rotate it. The internal advance weights have to be clean, lightly oiled and intact with no damaged return springs.
What distributor number do you have?
Bill

[Bob Ashlock]

I resolved the worn distributor problem by installing a 123 Tune. The electronics stabilizes the advance and resolves the 'deadly embrace' issue caused by a 'loose' distributor that sneaks the idle advance up, letting rpms increase, advance increases more, etc. etc. resulting in an idle that drifts way up. My 'test' for this is, when idling in gear, lightly load the engine by letting the clutch out a tad to slow the idle back to normal, then re-engage clutch and see if rpms stay lower or do they slowly creep up up up again? Talk to Ed Madac at 123ignitionusa.com

[Agb]

Thanks for the feedback guys.
I am running a 123 distributor plus have checked all the moving parts which seem to be working as required. Seems I can get it idling ready nice and run it around for a bit, then it seems to drop of sometimes. Can work it out
Plus
Last time I was working on it I noticed the linkage from the fan shroud to the carbs, thus not allow for the offsets of the carbs.
Has any one else noticed this or am I seeing things? Regards Andrew

[derekbou]

what curve is loaded in 123?

are the floats set properly to spec on the webers?

have you experimented with different idle jets - specifically next smaller? sometimes if a slight rich condition idle can drop if idling for a while

this is all in addition to be absolutely sure the linkage is set per the diagram