Anybody with carb experience?

Do a search, there are some very good threads on adjusting the carbs.

 

here's a good URL for it :

http://www.r-design.net/308/index_e.html

of course the ugly guy in it doesn't know much

 

While not a 308, here is a thread possible describing the same symptoms as your car and a possible fix.
It is sometimes very helpful to cruise some of the other car sections as some real technical tidbits are all over the board.

http://www.ferrarichat.com/forum/showthread.php?p=136942381#post136942381

I'd also agree that the GTB Register tech tips section with articles by the brilliant Carl Jones are well worth reading - a great guy and his words are gospel.

 

I believe that unless it is a major stumble that this is normal of the carb cars. I have had a "slight" spit in the mid range when you accelerate which after a few carb tune ups still cannot get rid of. This is not a problem in normal driving it only does this when I back off and hit the trottle . Normal highway/city driving is OK and acceleration up to 7K is great. I just let it go. So unless you have a major hickup get used to it. You will find here that a lot of folks will start telling you to change jets and emmulsion tubes and check the floats but this will only cost $'s and may never fix the concern. So my net is as long as there is no problem to the engine then let it go. I would take a look at the plugs and as long as they are not running lean or they are running extremely rich , just let it go. My 2 cents here. Enjoy the ride

 

Good carb tutorial by Birdman. http://home.comcast.net/~jonathan.bird/index.htm

 

"Excellent" carb tutorial...

A friend and I followed it to tune and synch his 1978 GTS, with great effect; it sings like an angry bees nest.

The idea that stumbling and coughing/spitting is normal behavior for these cars is misguided.

 

you might have an over rich condition - standout occurs when you hit the accelerator hard, and fuel/air mixture flies out of the top of the carb throats. I could actually see this when driving with the rear bonnet removed and top of air cleaner removed, and viewing the occurance in the rear view mirror.. a nice flow thru exhaust cured my standout. pulll your plugs and diagnose, if you are running ruch, step down the main jets a size.