350 CHEV in a 1987 camaro.. idles rough......any ideas

i have a 1987 camaro with a 350 chev 5 speeed  , holley 600 carb, and i need ideas on why it wont idle when your driving and come to a stop. its the only time the engine wont run strong. When the car is stopped or in motion , there is no noticible problem with the way it runs, it goes good. just when your shifting down and come to a idling stop that it chokes and sometimes dies. i recently changed jets to a 72 and it runs fine with a ton of vacuum. it has dual alternators and batteries with an electric cooling fan wich loads the engine down a little when it come down to an idle.  

Have you check for any vacuum leaks.  
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my other account is locked up .... but yes , i checked for vac leaks and found one, now it runs like a top, thanks a million!!!!!!!!!!  

is the converter not locking up or does it stay locked.  

Well it ran good for a day and is running rough again, is it possible the vacuum advance needs to be replaced?  

Doesn't hurt to change the vac. advance. Another thing to look at is the carb. If you take the floot bowls on and off alot and over tork the bolts, the carbs tend to suck air or dump feul randomly. Check that to. check the base of the carb. for straightness. Sometimes when the pvc port gets put in a small lump forms causing a small gap between intake and carb. Use a fine file for that.

hope that helps  

Well i removed the carb, and the pvc port looks fine, but the base gasket was not the right size, i bought a size smaller and it now seems to look tight and allows the butterflys room. i see what u meant by over toruqing the bowl bolts lol . i cleaned the needles up good and now i am going to try assemble it . The distrubutor needs to be turned one tooth back because it is right up against the air cleaner. do u need to prime the oilpump and turn it or can u be succesfulo in doing it by puliing it and turning it back one tooth?? Is gasket silicon recommended when installing a carb base gasket??  

To answer you Q's. No need to prime the oil pump unles you have some rad. motor. If it was running before everthings already lubed. If the dist. is hitting the air cleaner then turn it back 2 or 3. DO NOT put any silicon on the carb at all. under the carb. is 2 circits. one is the blow back valve and the other is the power valve.

Did you find the problem?  

Well i traced the problem to the spark plugs,, they were fouled badly, due to the original problem of wrong jets. Its a 600 cfm holley , the jets i have in it are 64's. It seems to run a little richwith them. I have 62's and 72's, can anyone give some input on wich set i might want to run with???? Tanks for all the help , shes alive again!!!!!!!  

did you hook up a vacume meter to check your intake vacume. if thats not done right then no matter what jet you put in the motor will run to rich or to lean around idle and crusing speed.

if you need help tunning your carb. let me know.  

it runs good and starts with a click of the key now. It will lay plenty of rubber now. thanks for all the help.  

hey bud. forgot to mention. find a strech of road and run it hard for about a quarter mile. Then pull the numder 1 plug. That will give you a good baseline of were your air/fuel is. Should be about brownish red. black is rich. and white is lean.

This might help in finding the right jets.  

good trick i will try that