POLAND_SPUD wrote:maybe post a pic of this design as your expelnation doesn't tell me much... (sorry... it might be my fault though.. it's late and I am quite tired)
Still working out the design. I think I got overexcited last night, when I tried to draw out what I seemed to visualize so well, it just didn't come together well (Yet).
Here's an explaination of what I came up with:
I was thinking the fuel side would be larger diameter.(imagine one half of the pipe length).
When the fuel enters (through check valve), it presses a piston which has a small diameter rod extruding into (other half of pipe) the smaller diameter of the pipe.
The smaller rod presses a check valve on the air/oxydizer tank and the air/oxydizer enters into the smaller ID/ smaller volume half.
seems like the two would equalize and could somehow(? hose from each side "T"'d to the push button valve OP???) Or be triggered based on piston position.
It's sort of like, imagine the spring from the stick type tyre gauges (the one's that have a spring inside) and made the surface area of the plunger say twice as large, when it read 100psi, you'd actually only have 50 psi, because twice the surface area is pressing on the spring than normally.
(Pretty simple but it got me excited so far)

8)
The idea started when I was looking at JSR's mini-hammer valve, imagining a check valve on each side, and the hammer spring could release the hammer the fuel check valve, The fuel pressure would shot it back at the oxydizer valve, and they both would vent into the firing chamber. It would require fiddling, but heck a lot of good mechanics don't like carb work even.
I was also imagining a cylinder where the fuel enters (through check valve), and presses a piston forward,
as the piston moves forward a port hole is exposed in the cylinder wall and the oxydizer enters through port (w/Check or one-way valve),
Giving it the necessary pressure to press or activate a pilot valve,
to cause the (proper) mixture to dump into the firing chamber.
edit: Or it takes place in the firing chamber and the piston is a BFB, and when the pressure moves it far enough (also loading shot), it switches the spark on.
Had another I haven't woked out, and not sure if it makes sense, where the hose on one side of chamber enters into the other side of chamber as well, pressing a piston center, ...still trying to figure if it's scientifically possible though...

8)
Anyway not to "hijack" It's still on topic due to the valve and similarities IMO So any thoughts on that?