I've got a 66 coupe 6 cylinder, when I am accelerating
then push the clutch in or put it in neutral, it like idles really high. Then if I put my foot behind the gas pedal and pull back, it calms down.

Could this just be the return spring? Or maybe the pedal assembly linkage? Or a carburetor problem.

Also, I want to get a new carburetor but do not low which one is good to get with the 6 cylinder and I do not know which one I currently have. I assume it's the normal autolite one but I'm not positive.

 

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it is sticky linkage or weak return spring or worn throttle shaft

if you still have he orig distributor you need a 68 or later if you use a non stock carb otherwise you will not have any ignition advance.

 

I believe it's the original distributer but not sure the cap looks brand new. Maybe sone one just replaced the cap lol. So what do you mean I'll need a 68 or later

 

try moving the linkage by hand to see if it returns all the way. Also where is your return spring attached? There are a couple different places it can hook, which can give different throttle feel. Mine is hooked to the end of the intake log, which makes it have a strong return.

 

Well, I work at a shop and we messed with the choke a little bit and it made it calm down but I do need a new return spring. The one that is on there is not the right one and its really weak so I think when I get the right one, it'll be okay.

I am still planning on getting a get carb though.