heat related mix problem

[gmr714]

I recently bought a 74 260z with Hitachi Carbs.I did a complete tuneup ++ and then had the carbs adjusted for $$$. It seemed oK at first. Now I have a problem with the way it runs if I start it while it is still hot. It runs pretty good for 50 miles but if I stop for gas or a soda then I start it back up it will stutter and run very weak. The engine temp stays low. I have to pull the hand choke all the way back to get power under load. It does not stall out. I have been through the vapor lock theory, and it is not the problem I think. I ran new fuel lines and insulated them , the pumps are new with good pressure. When I have this problem I can drive it for miles and it won’t smooth out, shouldn’t vapor be forced thru? I need to shut the car off for 15 minutes and it runs fine again. I found that the temp sensor on the air cleaner is missing and the air control valve on the intake does not function, should I close it so it only draws fresh air all the time? also the vacuum control valve is inoperative as the wire is torn off. The EGR has also been disabled since the diaphram was leaking and the VAC line is capped. When I pull back the choke am I cutting air or adding fuel or both? The vapor canister is also disabled.I have been attempting to figure out a way to adjust the idle speed and mixture also but all I have is an untrained ear and a screwdriver. I am a new Z fan and would appreciate any and all input on how to troubleshoot and get this car running smooth without replacing all of the above parts.I have antique plates ( no inspection or emissions) It is a driver not a show car. Thank you for your suggestions

Mark in PA