You need to be setting up using the air bleed and balance each pair together and then you can balance between the two pairs.
https://www.youtube.com/watch?v=tjf4QbtqTZA
Carb Tuning Company in Southampton??
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Re: Carb Tuning Company in Southampton??
Thanks makes sense Dick after all it is measuring how efficiently it can compress...
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Re: Carb Tuning Company in Southampton??
Jeffw, probably a stupid question but how do you adjust the air bleed on a single pair of a weber DCOE carbs
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Re: Carb Tuning Company in Southampton??
There are two air bleed screws, one on each part of the pair.

this diagram has them as air bypass screw, slacken the nuts off, adjust them so both parts match on the synchronometer and then match the two units to each other.

this diagram has them as air bypass screw, slacken the nuts off, adjust them so both parts match on the synchronometer and then match the two units to each other.
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Re: Carb Tuning Company in Southampton??
Managed to spend some time on the car yesterday
:
- sprayed brake cleaner on the carbs when they were running - no change in revs or running so assume no leaks.
- reset idle mixture screw to 1 1/2 turns from closed only on low flow carb
- when engine was warmed up, adjusted air bleed screw to even out flow (around 1/2 a turn) for this carb.
- had to adjust the idle mixture screw on this carb by around +1/2 turn
- adjust the balance between the carbs slightly and I achieved a reasonably even flow between the carbs.
- had to correct down the rev from 1100 / 1200 to 900prm.
The result in the engine is running smoother although possibly not as smooth as I would like but that could be my imagination!
Does the above sound OK? Is there any risk that I could be running lean for example?
Alex

- sprayed brake cleaner on the carbs when they were running - no change in revs or running so assume no leaks.
- reset idle mixture screw to 1 1/2 turns from closed only on low flow carb
- when engine was warmed up, adjusted air bleed screw to even out flow (around 1/2 a turn) for this carb.
- had to adjust the idle mixture screw on this carb by around +1/2 turn
- adjust the balance between the carbs slightly and I achieved a reasonably even flow between the carbs.
- had to correct down the rev from 1100 / 1200 to 900prm.
The result in the engine is running smoother although possibly not as smooth as I would like but that could be my imagination!
Does the above sound OK? Is there any risk that I could be running lean for example?
Alex
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Re: Carb Tuning Company in Southampton??
You need to set the mixture screew buy wind it out say 2 1/2 turns then turn back in slow the sweet point is you will hear the engine tone change. At this point turn back 1/4 . Do this for all 4
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Re: Carb Tuning Company in Southampton??
thanks for the help you are giving Dick
!
Could I have overdone the air bleed screw adjustment... or will this show up in that the carbs will not want to balance easily as carb with the adjusted air flow will not be running at the correct mixture ?

Could I have overdone the air bleed screw adjustment... or will this show up in that the carbs will not want to balance easily as carb with the adjusted air flow will not be running at the correct mixture ?
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Re: Carb Tuning Company in Southampton??
Yes you can easily overdo the air bleed adjustment screws
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