Thread: Was running good

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What kind of carb do you have? If you said in your post, I missed it. It sounds like you may have your idle mixture adjustment out of whack, and maybe your fast idle and/or choke needs a little tweaking. There are some (several) on here that can explain this better than I can, but do a search for "idle mixture adjustment". Good luck.

The Holley could have a warped body where the metering block goes. This warpage allows a vacuum leak, and sucks gas directly into a vacuum port. Remove the float chamber and metering block and check the face of the carb with a straightedge. If its warped, use a fine file and dress it flat.
The warpage is caused by overtightening the four long screws that hold the chambers on, tighten them gently and in rotation.
Also can be caused by the cork gaskets shrinking. The newer composite gaskets don't have this problem.

The carb is 650 cfm holley single feed vac. secondaries, I have the electric choke, all is set open no choke working on it, it is not hung on or binding, the floats have been set and checked, new needels and seats for them, the idle screws when turned all the way in makes the idle increase instead of decrease like I have seen so many times before, the truck is extremely rich to where you can hardly stand behind it. It carbon fouls every plug even with the delco 45's in it. It sounds like it has a full race cam now, used to run smooth and have a tad lope to it, now have wicked lope, sounds like some old race motors I used to build with huge cams,

I have gone through them, cleaned, there are all composit gaskets now, I will pull it apart tonight check it all again, see whats the real problem, and the vac. gauge was very quick on its movement like 4 times a second fast. So maybee the valves? I will try to pull the valve covers to see if I have a broken valve spring, just dont know why its always been so rich never has been lean since I have had this carb,