Single carburetor setup, Setup single carburetor/distributor for a 1.8 Options

[cmxiv 74]

Hi, I need to know if anyone around has a functional, decent (not performance, not perfect) setup that involves a center mounted carburetor on a 1.8 L engine. While I'm new to the subject I'm well aware about the inefficiency of the center mounted single carburetor setup on 914. Yes, it sucks ! But I have to deal with the facts and the reality. This are the facts: I bought my 74 1.8 already converted on single carburetor, (looks like a Weber, made in Spain, no other markings visible without removal) paired with a centrifugal advance distributor (not sure what model, no markings visible without removal) not know when was converted, or if the engine is stock or not. While has a decent acceleration response, decent power it runs very bad, inconsistent warm startup, high idle, rich, overall I can't find a "sweet spot". So far I changed the points, condenser, wires, spark plus, spark wires, distributor cap and rotor. The car is in what I call "active" repair/restoration which means that I have to keep it running and do work on it whenever I have the time and a place to work on it. So far is in my friends shop but while I will continue to have shop access I can not keep it there anymore, so it has to be parked on the street (it is registered and insured). For now I have to keep the car running with a single carburetor, so any other option is out.
Now... not sure if the centrifugal distributor is a good idea for this already bad setup, but I need opinion and advice from people who know how to do a proper setup for a single carb. I will add more info and photos over the next days Thank You !

PS. It looks like I have a 1.7 L not 1.8.The engine serial nr starts with EA, assigned to a 1973 1.7 L.

[Al Meredith]

try two things: One, I remove the thick plastic intake gasket and replace it with a metal gasket. This way the heat from the head will transfer to the long runners and heat the intake charge. Second, replace the idle jet with a larger jet. The carb was probably jetted for a VW engine.