I had a QJ on a 69 Buick Grand Sport that never failed me. When you hit the gas it would open up and things started moving. I did rebuild mine and I used over the counter carburetor cleaner to get the grime off. The biggest problem is getting the floats set right. I guess I got lucky with that since it was my first time. Now would be the time to drill out the jets if you want a little more power.
kwg
Once I figured out the metering well plugs were leaking on my mothers 1966 Riviera and caused hard starting in the mornings, couldn't have asked for a better carb on that 425 nailhead. That particular carb was almost an 800 cfm model, IIRC. I'd suggest finding some smaller diameter metering rods instead of drilling the body, or find someone who had one of those tiny Unimat lathes and turn an existing metering rod down. The sheriff of our county who was a good friend, asked me one time if there was any way I could get that car away from her as she taught school about 15 miles south of town and knew only two speeds, stopped and wide open. She passed by his office everyday going to work and he said if she was running a little late he'd radio his deputies to look the other way if she passed them. I asked him why he didn't give her a ticket like he did me and he said " Ain't gonna happen".
