pressure regulator

[DuMaurier 7]

I did see your suggestion Richard , but I already have the 150 psi Demand pump , and I'm only seeing the internal bypass ones rated at 100 psi , also , using a regulator woulg give full adjustability and a 1:1 rising rate just like with the fuel system.

[Richard L]

You can get 125psi springs and the conversion kit cost less than 30 dollars. Nothing stopping ypu shimming the springs seat.

[DuMaurier 7]

So now I have to look for a sale for my pump ? :roll:

[Richard L]

you don't need to sell your pump, just order the by-pass add on - you just change the front part of the pump.

[DuMaurier 7]

Cool , I didn't know that I could do that , can you post a link ? , I'll look for it in the mean time.

[Richard L]

Originally Posted by DuMaurier 7

Cool , I didn't know that I could do that , can you post a link ? , I'll look for it in the mean time.

I believe the part you need is 94-380-38 - it is a pump head with by-pass. Make sure it comes with 125 valve springs.

Need to ring Shurflo directly for stock. http://www.shurflo.com

Richard

[NAnderson]

Originally Posted by DuMaurier 7

I am thinking of using an ordinary EFI adjustable pressure regulator to kick back to the tank and have the pump turn on/of when the MPS is activated @ 12 psi therby totally eliminating the pressure switch . After a bit of searching the only 0-200 psi EFI pressure regulator that I could find was the WELDON 2040 and 2047 , they are sold for $ 224.29 and & 318.57 respectively, a bit pricy , but they will get the job done.

Just wondering if any more has been discovered about using an EFI boost-referenced adjustable fuel pressure regulator with a water/alcohol injection system. I guess the biggest stumbling block would be the (much) higher base pressure and how the regulator would hold up to the increased pressures. Most EFI systems have a base pressure of ~43.5 psi and then rise 1:1 with boost from there. The water/alcohol injection systems would have a base pressure ~70-90 psi and then raise 1:1 with boost, ending at somewhere in the ballpark of 90-120 psi of water/alcohol pressure (boost dependent).

I've got an AEM universal adjustable fuel pressure regulator I'm going to give a go this year, but I'm somewhat apprehensive as to how it will react to the higher pressures, both base and absolute. We'll soon see.

Originally Posted by DuMaurier 7

One thing comes to mind though , By using one of these regulators , I will be trying to get my WI system to function like an EFI system with a continuous return , but remember that the EFI system runs CONSTANTLY , so that the system is always pressured making fuel available to the motor all the time , when the motor is shutdown however , the whole system DEPRESSURES ! , this would be bad for a WI system , since after periods of -injection there wouldn't be any residual pressure in the system because the regulator is open and bleeding the pressure to the tank , before the next injection event one would have to wait for the system pressure to build before any injection can commence , this can be very undesirable , and in a system like mine (with flow sensing ) , boost will never go past the WI treshold pressure set on the MPS ,since it will be limited by the DDS3.

This is one area where the pressure switch on the Shurflo pump may actually come in handy! Let me expand.

You could wire the MPS to kick the pump on, completely bypassing the pressure switch on the Shurflo pump, so whenever the the MPS was tripped the pump would be constantly on thus activating injection. That you covered above. As for the pressure switch, you could wire that up to a switched 12V source so whenever the car was turned on the pump would run initially to pressurize the system but then turn off whenever it hit the set pressure switch point (probably 5-10 psi below the adjustable pressure regulator setting). Also, if during normal driving the system slowly bled down pressure the pump would automatically repressurize the system. Granted, there's a ~15 psi swing in the turn-on point of the Shurflo pressure switch, but it'd prevent the system from fully depressurizing and would automatically pressurize the system upon start-up.

Just a though...

[DuMaurier 7]

A friend of mine wanted to set up a WI system and offered me a good price for my pump so I sold it to him and I'm going to get the new Aquamist/shurflo 150psi internal recycle pump ..............just keeping it simple is always the best way

[NAnderson]

Originally Posted by DuMaurier 7

I'm going to get the new Aquamist/shurflo 150psi internal recycle pump ..............just keeping it simple is always the best way

That's a very good option and keeps things nice and simple. The only downside is that water/alcohol pressure won't increase on a 1:1 basis with boost.

I'm planning on running 30+ psi of boost and having linear water/alcohol pressure against manifold pressure is one of my paramount concerns. At 30 psi of boost a 100 psi pump would only be putting out 70 psi at the nozzle, thus greatly changing the flow rate. Not exactly what I want. Yes, it's a little more complex but my whole system is over-engineered so it just goes with the pattern. :lol:

Anybody else have input or suggestions on pressure regulators and water/alcohol injection? Still waiting for some of the big names to notice the forum is back online...

[fperra]

Couldn't you just pressurize the water tank with boost pressure?