As has been said, a "remanufactured" carburetor is not "brand new". As with all "remanufactured" parts, many "remanufactured" carbs are garbage right out of the box, especially for older and less popular applications where the carb may have been sitting for years. Yes, Holley has a "remanufacturing" division that puts out all makes of carbs, not just Holleys.
Drilling? Eek! No, this is almost NEVER the right solution and stands to make things very much worse overall. Don't do it again.
This calls for systematic diagnosis. Did you, with the engine off, operate the throttle linkage while looking down the carb to see if you get a nice strong shot of fuel from each accelerator pump jet? Did you check all the hold-together screws *including the ones accessible from underneath, on the throttle body-to-manifold mating surface* for tightness? Looseness of the bottom screws is a common cause of hesitation in BBDs.
In cases where I'm forced to use a reman carb for one reason or another, I usually wind up having to go through and rebuild it with a carb kit because the float is often bent and almost never set correctly, ditto the onboard linkages, the accelerator pump cup has seldom been properly prepared before installation and so does nothing, etc. This last is probably your problem -- the leather accel pump cup MUST be oiled and "flared" with a small screwdriver before it is installed. If it is not, the accelerator pump will barely work and you'll have a large flat spot.
|
That reminds me of the last time I rebuilt a carb for my VW. My old one was California emissions, with an altitude compensator. The throttle shaft was worn, and none of the popular non emission carbs I had for parts would interchange with it, so I built another one. After fiddling with it for about a week I discovered someone had drilled the main port out to a ridiculous size, and the fuel consumption was terrible; I burned a 1/4 tank of gas in 20 mins! I ended up switching port sizes about four times before I found something that worked well. This was 50 000 miles ago and four years later it still works beautifully. I suggest gathering up about a dozen cores and pulling the ports out of them. You can swap them out like I did until something works.