Mate im not that experienced with carbies but from that post above it sounds like you are struggling to get enough fuel in the mix, maybe you should upgrade the size of the SU or add a second, it would be beneficial in other ways too obviously air flow

Thanks guys, great info. Will check all the listed areas today. I seem to think that the needle in the SU may be bent or a little distorted.
When doing the dynoing and shaving the needle for fuel requirements, the needle resemble a thin sewing needle by the time i had finished and was very, very thin at the wedge end.
Does anyone know of any material other than brass that needles can be made from. I have recorded the increments of my needle in 1/8 inch sections and can fabricate a needle if need be... just don't know what to use...

from past experience on a s/c mini i knew, coud it be that the bearings are strving of oil as the boost is pressuirsing the sump by blowing past the rings, and the cugging is due to the oil starvation and cavitation.
long shot but possible.
also the s/c should be making consistant boost not risiing if a toyota ageze model, is it starving uder low revs and the secondries opening up making it run ok later on in the carb? might need larger idle jets depending on carb.
also sounds like dizzy or vacume advance.
with boosted angines i have always been told to lock the dizzy timming to prevent problems. lower hp overall but no tuning problems

have u checked your compression? sometimes when compression is down in 1 or more cylinders the motor can be rough at idle. with boost u may have burnt a ring or valve if u have leaned out. but maybe im talkin crap

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mate thatd be bloody exellent, give us a bit of info when ur comin up or wateva and yeah, be good to talk to someone about whose done the same engine as im building, u may be able to stop me from doing things the hard way etc.
cheers mate.

check those inlet hoses. there's 3 of them, and they equalise the pressure across the supercharger at idle when the pulley is switched off. if one is leaking, it will cause a slight vacuum leak; or a pressure reversion, causing your engine to suck more fuel and less air, resulting in an overly rich mixture at idle and the chugchugchugging you mention.
they would be my first check point.
other than that, check your SU needle isn't damaged and flooding it at idle.

either way, it sounds like it's running overly rich at idle.

Oh man, now I am really interested in seeing a photo of this set-up as well. What kind of HP are you getting outa the blower A14? In hind site would you have gone with anything different? A15? other? This sounds awesome, well once you sort out the chugging thing, which you will.

What carb are you running? When I had the a12/Hitachi in my car it had the same problem all of a sudden. Took out the air bleeds(gotta take off the carb top to do this if I remember correctly), after careful examination, a tiny piece of gasket was lodged in the small hole. When it was removed, the engine purred once again!
Also, check your distributer advance isn't loose/sticky or something.
When in doubt, I always go back to the basics; check for steady vaccum and do a compression check.
Are you running big valve springs? Double ones? May help to pull the valve cover and check to make sure the lobes aren't chasing the base circle.....going flat.
Hope this helps a little.
-Donnie

does it do it with the blower clutch disenguaged?
What size is your crank pulley?
Once I get a WOF on my sunny Ill be fitting the sc14 to my a14.

Its not ch uging because of flooding at idle is it? Just a thought.