Ethanol works as a super cleaner-it will release any old goo/varnish in your fuel system.If your old car is new to ethanol based fuels-not uncommon to have a fuel filter plug up within the first couple weeks.Change it out and you are usually good to go.
READ THIS TECH INFO FOR YOUR CARB FROM EDELBROOCK,,,, http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf
StarTron is the best..It even takes old fuel and makes it better..Great for gas that's been sitting for awhile.
Between the **** ethanol and the fact that you can't seem to be able to buy effective carb cleaner, I've seen carbs lately that need drill bits of the correct size, turned by hand, to clear some of the small p***ages.
One of you idle circuits is clogged. When you start to open the throttle,the idle circuits shut off,therefore the engine runs smooth. CLEAN THE CARB!
First thing i would do is run a can of SEA FOAM through it .If it sets for a while, the ethanol eats on everything. I usually don't believe in mechanic in a can, but sea foam is good stuff.I have have had mine going for about 10 years,NO PROBLEMS,UNTIL THIS SUMMER. Talked to edelbrock guy at nats, He said the fuel is killing the aluminum/rubber in carbs.I will put a kit in soon. Good Luck
http://www.edelbrock.com/automotive/misc/tech-center/carb-tech-videos.shtml 10 years since a rebuild? C'mon, man.
I've used Startron and Stabil 360*. The Statron came out first and I used it until the Stabil 360* came out and then changed to it Don't really know which is best, but I have used the original Stabil for years in seasonally used stuff like lawn mowers, weed eaters, etc. with very good results, so that's why I changed to their product. Since non ethanol gas became available ( at a much higher price and only in 90 octane) I use it in the yard equipment along with the original Stabil.
To make an Edelbrock carb look good is to remove the "Edelbrock" from it. Nothing looks as bad as a dual quad setup that had Carters on it and seeing two Edelbrock's.