OK, so I've read and read and read some more about multi-carb setups and I'm still having problems. My situation is as follows: I'm running a Weiand Drag Star 6X2 intake with Holley 94's (8BA's) on a Buick 401 nailhead that has been bored .040. Manifold vacuum is steady around 15 inches at idle. I don't know if it has an aftermarket cam but would assume not. I bought the intake and carbs in a complete set that had been run at some point with a solid linkage (non-progressive). The outside 4 carbs had their PV's leaded shut (the hole in the base) and the center 2 were running factory 7.5's. They were all running 51 jets. I rebuilt all the carbs and bench set them. I also switched to a progressive linkage using the center 2 carbs for primaries. It fired up and ran, but was really rich on idle. It did clean out once it was revved up, but when you burped the throttle it would belch black smoke. I took everything back apart and double checked everything. I adjusted the linkage so everything was timed correctly. I also bought and installed PV blockoffs in all 4 outside carbs just to make sure, and then installed 4.5's in the center 2 carbs. I checked all jets and they were correct, so I drilled out the jets in the outer 4 carbs to 53's and left the center 2 carbs at 51. I got in touch with Daytona Parts in Florida and ordered a mess of gaskets, as well as "better" leather accelerator pumps and "better" needle and seats that are supposed to be compatible with new gas (these seem strange to me because they don't have a rubber "nipple" or cone on the needle, but rather a little rubber "puck" that's flat). I installed these and reset the float level to 1 11/32 up and 1 7/16 down. I also set the outer carb idle screws at .75 turn out and the centers at 1 turn out. When I fired up again I thought the problem was solved. I hooked up the timing light and double checked timing. It appeared that my problem was solved. Idle was good and clean and you could burp the throttle with little to no black smoke. It still has a flat spot right off idle if you romp on it, but I'm not sure if that is a carb issue. I took the car on its first real trip, 150 miles south to Joseph Oregon which is about 2000 feet higher than here. It ran rich when I got there, as I expected, so I played with the idle mixture screws a little and it seemed to get better so I ran it that way over the weekend. When I got home I drove it across town and it keeps getting worse and worse..... The black smoke has returned. When I drive the car, I notice that when I come to a stop it wants to flood out and die. I thought this was a transmission issue (I'm running a switch pitch 400) but now believe that it is actually because carbs are flooding the engine due to the braking action. I came to this conclusion because I live on a hill, and when I come to the stop sign at the bottom (car facing down hill) the car REALLY wants to die, even if I rev the throttle, and smokes like a locomotive. When I saw this I went to another hill and drove up it....the car runs fine. Then when I point the car down hill it loads up bad. Next thing I noticed is that when I shut the car off I can watch fuel leak out from apparently the throttle shaft on the front passenger carb. It never did this before. While I'm looking at the fuel leak I can hear fuel dripping inside other carbs (not exactly sure if it was all or just some) which NEVER happened before. I've driven the car for about 30 miles since I got back and in that time it has gotten a LOT worse. This last drive almost asphyxiated me and its not just exhaust, but more the smell of raw fuel. MY THEORY: Those new "better" needle and seats aren't working and its allowing fuel to flood the float bowl and therefore pour into the engine. Would this get worse if the car was facing down hill? I guess I need to mention that my carbs are mounted "backwards" on the intake with the bowls to the back of the car. Anyone have any other ideas as to where to look? One major question I have is about PV's. Like I said I've done a lot of reading and even talked to a local drag racer from the 70's and I've found 2 totally different theories on PV function. One side says that you need to add up the rating for ALL of the PV's and that number needs to be less than the manifold vacuum at idle or it will just dump fuel in all the time. The other side says that you can have a thousand carbs hooked to an intake and as long as every single power valve is rated for less than the vacuum at idle you are fine. Thus the confusion on my part. Logically, I am siding with the "thousand carbs" theory because the PV's have a spring that won't allow it to open unless it is exposed to a lesser vacuum than its rated for. Therefore, if I'm running 1 or 10 PV's that are 7.5's and my vacuum at idle is 15 none of them should open because the vacuum at each PV is over 7.5 inches?.?.? I know I've written a short novel here, but I'm hoping someone can shed some insite on my specific situation. I know every engine is different and I will have to tweak my setup to work for me, but something is definitely not right currently and I'm not sure where to head from here. I've tried to give all the information for my situation, but if I left something out let me know and I'll edit the post. If I had the coin I'd just buy 6 of the new 97's and be happy but I'm not in that situation and just want to figure these out. I have read over and over that 94's are "easy to tune" but haven't had that experience to this point. Please.....bless me with you knowledge and advice. Thanks.