timordog
Automotive
- Dec 20, 2002
- 4
I would like to see what you all think of this idea I have about a modification for a holley carburetor on a turbo or supercharged engine.
In regards to boosted carburetion I have never really liked the idea of using more where the situation really requires different functionality in the design. It is understood that the venturi effect which meters fuel in a carb is blind to boost pressure but I’m still not sure why no one has addressed this directly (that I am aware of) instead of apply all sorts of band-aids as I see them like more and more carburetion. I’m not trying to knock anyone, if it works then it works, but I think there must be some issues with low rpm drivability and mileage on a smaller engine carbureted this way for high rpm and high boost.
I haven’t worked out the details but I have had an idea I think would work that requires some testing to mechanically alter the main metering circuit of a holley carburetor under boost.
My idea centers on 2 mechanical pieces working together. The first is simple and it is called the adjust-a-jet.
This device allows simple main jet alterations with a needle as if it were a simple idle adjustment screw. This needle sticks up right from a new plate immediately after the main metering plate.
The second part is some sort of air cylinder impact driver. Something like a small impact driver which could convert the linear force of the charge pressure in an air cylinder into rotary motion to turn the adjustment needle on the main jet. I realize this would not be simple and would take development and testing to get working correctly but compared to allot of other devices on engines mechanically this is not really all that complex. I am not sure what to use as an actual impact driver will not work but there must be some other small device similar in function which would probably work well.
If anyone has an idea of something small enough that might suit this function it would be very helpful.
Also I need another way to seal the needle from leaking gas from the pressurized passage as the standard adjust-a-jet design uses an o ring seated by a lock nut which I would have to remove for the system to function.
Any thoughts, opinions, criticisms or direction is greatly appreciated.
In regards to boosted carburetion I have never really liked the idea of using more where the situation really requires different functionality in the design. It is understood that the venturi effect which meters fuel in a carb is blind to boost pressure but I’m still not sure why no one has addressed this directly (that I am aware of) instead of apply all sorts of band-aids as I see them like more and more carburetion. I’m not trying to knock anyone, if it works then it works, but I think there must be some issues with low rpm drivability and mileage on a smaller engine carbureted this way for high rpm and high boost.
I haven’t worked out the details but I have had an idea I think would work that requires some testing to mechanically alter the main metering circuit of a holley carburetor under boost.
My idea centers on 2 mechanical pieces working together. The first is simple and it is called the adjust-a-jet.
This device allows simple main jet alterations with a needle as if it were a simple idle adjustment screw. This needle sticks up right from a new plate immediately after the main metering plate.
The second part is some sort of air cylinder impact driver. Something like a small impact driver which could convert the linear force of the charge pressure in an air cylinder into rotary motion to turn the adjustment needle on the main jet. I realize this would not be simple and would take development and testing to get working correctly but compared to allot of other devices on engines mechanically this is not really all that complex. I am not sure what to use as an actual impact driver will not work but there must be some other small device similar in function which would probably work well.
If anyone has an idea of something small enough that might suit this function it would be very helpful.
Also I need another way to seal the needle from leaking gas from the pressurized passage as the standard adjust-a-jet design uses an o ring seated by a lock nut which I would have to remove for the system to function.
Any thoughts, opinions, criticisms or direction is greatly appreciated.
