Im sure most if not all of you has had a lean bog problem whey you do a super fast WOT some point in your life. Primary fixes of a lean bog are making sure enough fuel is in bowel floats set correctly, making sure accelerator pump is working properly and increasing pump throw, adjusting air valve by tightning spring or adding weight if an AFB.

I was thinking of an easy way to add weight to the air valve of an AFB without drilling and adding lead as all the books recommend. What about using very strong magnets? I bought some super strong small round magnets at a craft store. You can put them on the air valve weighted ends with out taking off the air horn. They stick like glue. Its hard to get them off. Has any one tried this with success? I really dont see how they would come off or get sucked down the intake. Anyone try this??? Is there a better idea to add weight to airvalve of an AFB?
Fish

Your far better off getting the air fuel ratio(and squirter circuit) tuned up on the front primary circuit to fix any lean bog at WOT, not the secondary air doors

sounds like those magnets are strong enough to stay put but I would JB weld em just for peace of mind (Mr Murphy is always lurking).

Ive got the accelerator pump travel already in the hole for the longest squirt. Pump seems to be working well, starts squirting immediately with throttle play. I dont know what else to do but add weight to air valve to keep it down longer to rich it up. thats also what all manuals say to do. It must be more of a common need or they wouldnt have put springs on the AVS and TQ.

if you block the secondaries completely from opening does this stop the bog? or is it just when they open? I'm assuming the float level/line size/psi (some of which you have already mentioned) are OK & no vac leak anywhere (that can be hard to pin down). & you are getting a real healthy squirt of sufficient duration? You mentioned that it is immediate, what about duration & checking in your driveway might be different then under load/wot so I asked about the overall fuel delivery capacity.

Is your problem when in neutral fast revving it to WOT or when driving it?
If when driving it bogs going to WOT do not add weights onto either the AVS or Thermoquad doors
You should use the spring tension to help you get rid of the secondary opening bog on both types of carbs., that works well once you get it right
BTW, how's the float level on your problem carb.?
Another thing to check on the AVS carbs. is the gasket on the secondary boosters, they can be wrong ones or installed wrong
Lots of gremlins out there waiting and wanting to mess with us hot rodders
Let us know what you find, it may help others on here later also

I would richen up the primaries a step.....
I had that problem with an Edelbrock AFB, tried all the springs, rods, pistons nothing cured it. Took a step up in primary jets, solved it..


Just my $0.02...

Just a band aid fix, carb is not working to its full potential. Fix the idle circuit, a lean condition means there is not enough fuel in the system to start with. Like covering up a fart in an elevator with pine sol, fart is still there.