Thanks for the encouragement.
Nearly got the swirl pot finished today. Just got to weld it and the baffles in.
Here's some detail on the fuel trap doors in the swirl pot section.
In this pic you can see the opening in the bottom of the swirl pot. Under braking fuel will be pushed forward and flow into the swirl pot from the rear section of the tank. The baffles help direct the fuel towards the inlet.
Inside the swirl pot the trap doors look like this.
The trap doors pivot on pins through the sides. The weight of fuel should keep it shut but I figured with all the bumps and cornering forces I wanted a way to keep it closed unless there was a flow of fuel incoming against it. I thought of using light springs to provide a positive way of keeping the trap door closed but springs aren't reliable. I set them up with counter weights in the form of the long screws tapped into the top of the hinge. These are set in pointing down on an angle. Gravity keeps the trap door shut and you need to tip it on a near 45 degree angle before it opens on it's own.
The counter weight work against the braking, acceleration and cornering forces. The trap door in the back when under acceleration the counter weights (The end being below the pivot point) clamp the trap door shut. While under breaking being they help swing the trap door open. In a corner the trap doors on the sides of the swirl pot work the same way. The door on the outside of the turn clamps shut while the inside one swings open helping the fuel from that section of the tank to flow into the swirl pot.
I guess it's not really a swirl pot and probably better described as a surge tank.
That's the theory, It's been fun to make and hopefully it'll work like I reckon. Holding the surge tank and spinning around on a stool while watching the trap doors has been the only testing so far
The other thing I've done is add a drain port to the tank. I figured it'd be useful to have an easy way to drop the fuel out of the tank especially if the car sits for a long time.
This pic also gives an idea of the finish I'm going for. The welds were nice but I wanted the tank to look like it was made from one piece so I've ground back the welds and rounded the corners. I like the look of the brushed finish on the Kirkhams and figure a brushed finish will look nice while hiding any scratches etc from dirt and stones under the car.
Cheers