Engine help please!!!!!!!

[BigPhattyVW]

Hello everybody!

Ok I am stumped . I have a 1600 dual port with 34pict/3 carb, 009 dist with a pertronix igniter 2 installed. When it is running for about 10 minutes with normal city or highway driving, it starts to stutter and lose power. Not all at ones but sporadically. I just recently tuned up the engine, and one by one installed new plugs, then a new cap and rotor. Each time I replaced an item the problem would disappear then come back about a week later. I could replace the cables or the coil next but I still don't know if that will fix the problem. I thought it could be an air leak, but all the articles on air leaks talked of a very rough idle and smooth acceleration, which is exactly the opposite of what I got

Any help or advice you all have will be greatly appreciated!
Thanks again
Clint