tom3,
You should be running B series rods, I'd try going one size bigger on the rods, IOW if you're running 45B, go to 46B or maybe 47B. If you can't find the rods, email me, I've got a bunch of this stuff in boxes out in the garage. I think 12.5 is prety fat, you should be able to get better than that w/o losing driveability. On the lean part throttle acceleration, sometimes going a size or two bigger on both the jets and rods fixes this. Same cruise, richer accel. If the car is running on the idle or transition circuit at cruise, you can drill the idle fuel feed with a jobber length 0.039 drill bit held in a pin vise. Allows more fuel into the idle circuit, you can re-adjust the curb idle with the screws and still get more fuel out of the transfer slots. Helps with cruise sometimes, well, lots of times. SOP for me on perf motors w/Q-Jets. You can get these carbs so dialed in you have a hard time tell it's not FI. People that ride/drive my 57 PU ask me what kind of injection I've got on it.
Fred,
I gave up on the epoxy-type repairs many years ago. NAPA and others have a little kit with two O-ringed metal plugs. There's two different diameters depending on year model. What you do is tear the carb down and file the lead rings off the plugs, this can be done on a belt sander if you're careful. Then reach down through the sec main wells from the top and drive the plugs out. My tool is a piece of welding rod about 4" long with a little crook in it to match the bend in the sec main well. Tap the plugs out with a hammer and this punch-like tool you've made. De-burr the edge of the holes and tap in the replacement plugs with a little motor oil for lube. A little foam piece goes in the recess in the baseplate, I don't think it's really necessary but I put it in anyway. Also, I have a small ball-peen hammer that I use to re-peen around the lead plugs under the primary main wells, go easy here.
If it drains off after this, try leaving it for a few days with the rubber line between the fuel pump and the frame pinched off and see if that makes any difference. I've had a couple that seemed to drain back to the tank through bad check valves in the pump. This makes absolutely no sense whatever from an engineering point of view since the needle and seat is quite a ways from the bottom of the bowl but it worked anyway. I've learned that if the physical results don't agree with my theory, believe the results and get a new theory.<g>
I'm told the Carb Shop can repair those inlet threads but I haven't tried them. They're somewhere in SoCal, usually have an ad in the back of the magazines. They're supposed to be a good source of hard to find Q-Jet parts too.
On the threads, I've never found any good solution other than the usual oversize, selftapping inlet nut, I think there's also one that a rubber part similar to a rubber expanding freeze plug. None of these deals pass visual inspection on a restored car. They don't always work, either. Good luck on the threads, if you send one to the Carb Shop, please let me know it turns out as I've got a couple of rare Q-jets with that problem. You can get the oversize fitting at NAPA or other large parts house.
Tom
[This message has been edited by tommob (edited 02-15-99).]