how to tune out bog ?
how to tune out bog ?
When trying to get rid of a bog I assume its the primary jets you change right>? after the initial pump shot of the squirters the fuel is coming throught the jets right? I am being told that its my squirters and to go smaller, I went bigger to get rid of a small stumble that I had when getting into the throttle. it got rid of it too. So now I am trying ot get rid of this bog any help?
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Car: 1988 Firebird S/E
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A bog while opening the throttle is rarely caused by the primary main jets. They should be with in 4-5 sizes from stock.
It is caused by either not enough accelerator pump fuel
or way to much. Or the shooter linkage needs adjustment.
Another possible cause is the wrong throttle blade position relative to the transition slots in the throttle bores @ idle.
Sometimes a motor with a big cam sees this.
This causes a flat spot when coming off idle.
The cure is to balance the throttle opening between the primary and secondary throttles. ( adjust the secondary idle stop.)
Make sure you have a PCV system properly hooked up and vented.
This little bit if airflow into the manifold @ idle is part of the design.
Also remove the fuel bowl and check the accelerator pump
fill check valve (ball) it must seat to allow the pump to function.
Remove the accelerator shooter and check for a check valve and a gasket below it. Sometimes they get left out during a rebuild.
It is caused by either not enough accelerator pump fuel
or way to much. Or the shooter linkage needs adjustment.
Another possible cause is the wrong throttle blade position relative to the transition slots in the throttle bores @ idle.
Sometimes a motor with a big cam sees this.
This causes a flat spot when coming off idle.
The cure is to balance the throttle opening between the primary and secondary throttles. ( adjust the secondary idle stop.)
Make sure you have a PCV system properly hooked up and vented.
This little bit if airflow into the manifold @ idle is part of the design.
Also remove the fuel bowl and check the accelerator pump
fill check valve (ball) it must seat to allow the pump to function.
Remove the accelerator shooter and check for a check valve and a gasket below it. Sometimes they get left out during a rebuild.
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RedLeader289
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May 28, 2019 01:47 PM




