348 Throttle Body butterfly reset?

I had my TB's powdercoated and the set screws were removed in the process. These are usually set at the factory and not supposed to be adjusted so is there a way to get it back to factory spec? Thanks for any help on this.

 

Butterfly stops. I will just adjust them to keep them from just barely closing and see what happens.

 

This is what I found for another model:

To set idle (some random notes i got from ferrarichat forum)
Use a small piece of paper & put it between the screw and the stop. Screw the idle screw up till it just grips the paper. Remove the paper & then add one half a turn. Then set the idle at whatever level you want using the air idle screw under the TB. You shouldn't need to touch the idle screw on the throttle mechanism after that.

Thanks for the responses, however I've got an '84 QV. I found a thread from several years ago searching for 'idle adjustment' and it appears that for the idle adjustment screw.........."place a piece of paper between the screw and tab on the plenum butterfly and tighten the screw just until the piece of paper can be pulled out then tighten another 1/2 turn." It then goes on to say ......."the air bypass screw should be fully seated, then backed out 4 full turns".*

I haven't tried this default position yet, but it sounds reasonable. I believe if the car will start from this point, the plenum screw should then be used to 'fine-tune' the idle to near 1000 rpm?

Reset the idle properly when the engine is warm. Piece of paper in between the throttle screw and the stop till it just catches then + 1/2 turn. Then set the idle with the air idle screw.

It's a very small value, but the "spec" is more based on how much the idle RPM drops when the air bypass screw is fully closed -- i.e., if the engine is at 1000 RPM during warm idle (with the throttle plate a little bit open and the air bypass screw open), when you fully close the air bypass screw, the idle RPM should drop to 450 RPM IIRC. If the idle doesn't drop enough = throttle butterfly open too much.
Turn bypass screw clockwise to restrict air getting into manifold thus increasing fuel mixture.
Turn bypass screw counter clockwise to increase air or CO in the manifold to decrease fuel in the mixture.

So does it sound reasonable to set the butterfly using paper and then one half turn? Is that 1/2 turn correct for the 348?

Or

I could mostly open the bypass screw and while car is running watch RPM as I close the bypass screw fully and confirm the RPM dropped to (450?) RPM and that will tell me that the butterflies are in correct position? Is 450RPM correct for the 348?

 

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This is why...

From my research it looks like you may be right. 3 thou is what pops up often across several models so I will try it out. For now I snugged them until a piece of paper was difficult to slide between set screw and stops then gave it 1/4 turn. Had difficulty getting them synced using the bypass screws and two ball jars filled with ATF. I ordered a Twinmax throttle body synchronization tool and should be here Wednesday. I’m worried there may be a leak in the tubing I used that was intermittent