How to maintain 100psi with 20psi manifold pressure?

[cmj]

I want to modify my setup with some type of regulator and or a water return setup to counteract the manifold pressure. As it is now my pump maintains 100psi but 100psi + 20psi manfold pressure = 80psi.
Any ideas?

[Richard L]

What system are you running at the moment?

[cmj]

Shurflo pump on/off solenoid and .7 aquamist jet. I plan on using an HSV controled by my engine managment but not until I solve this problem.

[Richard L]

One way to maintain a contant pressure for your water injector is to get a stainless manifold pressure regulator and feed the return water back to your tank, just like the fuel injection systems.

[b_boy]

Unfortunately the pressure is not additive, but as Richard suggests indirectly you might be able to use the manifold pressure as a priming pump that provides 20 psi of pressure pre-pump increasing the efficiency of the pump and sigificantly increasing it's output.

My plan is to use a self priming, self regulationg water pump to apply pre-pump water feed. Shurflo, Flojet, and a host of others make such pumps for on demand water systems in RVs and Yachts. It pumps until a preset pressure (usually 35-45 psi) and then turns itself off until the pressure drops (opening of a faucet or in my case Aquamist pump activity).

To use manifold pressure in the same way you would have to pressurize you water tank. It would have to be able to maintain 20 psi without leaking or exploding. Most poly propylene (think cloudy milk jug plastic) could withstand this pressure with a rubber gasket seal on the lid.

[JohnA]

...To use manifold pressure in the same way you would have to pressurize you water tank. It would have to be able to maintain 20 psi without leaking or exploding. Most poly propylene (think cloudy milk jug plastic) could withstand this pressure with a rubber gasket seal on the lid.
This could be a cheap'n'easy way to compensate for extra boost.
Good thinking! :D