351W/C4 currently running a Holley 600 cfm carb. Something is a little screwy with the carb, yesterday it was running great, today not so great. It will idle for a while then flood out and die. The gas just starts flowing right out the top of the carb. I suspect a sticky float, but I'm not really experienced when it comes to diagnosing and fixing carb issues. The plans originally called for a T-5 but it needs a rebuild so I went with the C-4 that I had. I have a brand new Edelbrock 650 with no kick down that was bought for the T-5. I also have a newer two barrel from a 73 302 laying around that does have the kickdown. Money is pretty tight right now. So, until I can scrape up the funds to get a kit for the Holly, should I run the Edelbrock and manually downshift when I need it, or run the two barrel? I would rather run the Edelbrock but I am worried that I might damage the tranny shifting it manually. What would be the best solution?
Unlike Mopar trans the C-4 will work fine w/o the kickdown feature working. The modulator adjusts throttle pressure so other than no kickdown above 40-45 mph no problem.
Edelbrock makes a kit to hook up the Ford kickdown... But to fix your holley, all you likely need is a bowl gasket and new needle & seat, not necessarily an entire rebuild kit...
you also try getting the car to run and pinch off the fuel line and when the car is about to die release the pliers, that'll sometimes release garbage buit up in the needle and seat with that rush of fuel pressure
Fuel bowl or the needle and seat is screwed. I just had this exact same thing on a brand new Holley. Changed the needle from my old one and now great. Ive also put 2 fuel filter on just in case. Change it out and make sure the little O ring on the needle is frsh and moves around. Take the boel off and sink it under water to makes ure there are no bubbles. If there is a pin hole it will sink it. You wont see it with the naked eye. Im not running a kick down either but just fpor the simple fact noone told me when I bought the carb and it didnt have one on it. It runs great just makes sure when you want to pass some one or going up a ahill dont put a lot of load on your tranny. I always make sure Im above 1300 rpm or down shift it. Thats all a kcikdown is used for...well other reasons as well but its also called a "passing gear" but it works as a vacumn to downshift your tranny...
had the same problem, fule running out while at idle. Old carb new fule pump. Changed nedle and seat new gasket, same problem. Put pressure gage on fule line 10lbs! put on regulator work fine. good luck