I have a 1775 with twin kadrons.
009 distributor with petronix 11 ignition , a bosch blue coil.
it idles sweetly for less than a minute and then drops in revs and splutters, a small blat on the accelerator brings it back to a sweet idle once again.Makes it a problem whilst waiting at a set of lights as take off when in the spluttering stage is non existant.
Does anyone have any ideas what the cause could be and how i can remedy the intermittent drop in revs ??
Many thanks to those who respond.

May be the distributer advance is holding up the idle if it is sticking, and after idling for a period of time returns further and lowers the idle. To check, use a timing light and watch what the advance is doing during the problem. Quite a common problem as not many people/mechanics lube the advance mechanism, although should be done every service. One drop of oil on the felt pad in the dissy shaft under the rotor. If not this I'd say next to check for an inlet manifold leak.

Thanks Matt, i will do the timing light check and see.
The felt pad has been getting its drink of motor oil frequently, but i dont know if the previous owner did ??

old kadrons floats would get holes in em and this would
cause float level to change.take the floats out and give em a shake to see if any fuel inside of them if fule in em replace em, if ok check that the float level is not set just a bit to high.