Pressure feed carb BS flathead

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A-RACING

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How can I eliminate short pickup in carb and then pressure feed the carb??? It's in a Stock appearing flathead, Big cam and all the "mean" stuff. Any ideas???
 
Pull the short tube, mill a slot from the fuel pump dump to where the short turn screws in. Then put a gasket on the carb, a plate to block the fuel dump hole and the short tube hole, in effect, the plate will force the fuel from the dump to follow the milled route to where the short tube was. Then another gasket and put it on the tank. Us a gasket as a template to cut you a thin plate, .050” to .125” thick.
 
Skidude said:
Pull the short tube, mill a slot from the fuel pump dump to where the short turn screws in. Then put a gasket on the carb, a plate to block the fuel dump hole and the short tube hole, in effect, the plate will force the fuel from the dump to follow the milled route to where the short tube was. Then another gasket and put it on the tank. Us a gasket as a template to cut you a thin plate, .050” to .125” thick.
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Thanks a lot. Will try. Have some good tanks, where someone had removed the pickup cup in the tanks, trying to bypass such. with a pickup straight to the tank bottom. Didn't work. Again, thanks for the info.
 
Does the tillotson act a bit like this? I’ve heard it called similar to fuel injection, kinda spraying the fuel into the intake?
 
The tillotson, having no accelerator pump, requires a very rich idle screw setting to get enough fuel until airflow is sufficient to make the power circuit start flowing fuel.

The setup described above will flow as much fuel as the diaphragm can push thru the jet, regardless of throttle blade position.

The good side is at low rpm with the throttle closed, the diaphragm does not pump as much.
Still much more than needed.
 
Truckphone said:
Does the tillotson act a bit like this? I’ve heard it called similar to fuel injection, kinda spraying the fuel into the intake?
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No, a Tillotson uses a needle valve, fulcrum and spring to regulate how much fuel enters the body of the carb, which is where the fuel enters the metering passages of both high and low side circuits. Changing pop off changes fuel flow and pressure in that area, so it is controlled independent from the fuel pump side. The pumper stock appearing carb is constantly pumping fuel into the metering are. The needle valve does adjust flow but pressure changes with the RPM of the engine.
 
Skidude said:
No, a Tillotson uses a needle valve, fulcrum and spring to regulate how much fuel enters the body of the carb, which is where the fuel enters the metering passages of both high and low side circuits. Changing pop off changes fuel flow and pressure in that The area, so it is controlled independent from the fuel pump side. The pumper stock appearing carb is constantly pumping fuel into the metering are. The needle valve does adjust flow but pressure changes with the RPM of the engine.
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The Tillotson TCT is not a pump diaphragm carb though......

https://www.eccarburetors.com/Tillotson-TCT-Carburetor_p_2148.html
 
CarlsonMotorsports said:
LOL -- I coulda saved myself some time answering this question elsewhere if I had already seen this post.
Skidude's on it.


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Brian Carlson
Carlson Racing Engines
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Skidude Knows his carbs!!!!! His tillotsons perform better than any I have used, from the biggest name builders,
 
I did several a EC's where we drilled from the pressure side of the flathead carbs pump ,right into the bore with a .015 bit as a constant feeder. Chucking that bit up was fun.
 
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