who's using a RRFPR?

[Pit Viper]

I'm trying to re-size my nozzles, since I've changed my turbo setup recently.
My issue is that I'm using a boost-referenced fuel pressure regulator, so I'm a little unsure on how to pick my nozzles.

I'm running the HFS-5 system, so that it injects on the fuel injector pulses, which is great since it increases injection as your fuel consumption goes up.
However, with my rrfpr, I'm increasing fuel pressure with each pound of boost, so I can increase my turbo pressure without changing my injector pulse width at all.

My fuel injectors are 680cc at 43 psi, so if I size my nozzles at 15% or so based on that, then they're not big enough when I'm running 20 psi of boost, as my injectors are flowing a heck of a lot more.

Any thoughts?

[Richard L]

Hello Pit,

We have a user have this arragement, a proper-return to tank set up...



he also runs port injection.

[Pit Viper]

Richard, what are you doing to me? :lol:
Hmm. So, now I need to run a rising-rate water pressure regulator. :twisted:
I may need to rework my layout somewhat.

did he really run a boost reference line to his trunk?

[Richard L]

Sorry Pit,

If you hadn't ask :roll:

More picture info for you:






They say, no pain no gain... :twisted: yes another long hose from the enigne bay, that what he did. Before you decide on this, I need to send you a non-by-pass fitting for the HFS pump.

[wizegi///m3]

Richard I too will be running a RRFPR with my M3 and now this has raised a question.

In a previous thread I asked if you had a nozzle to use with my setup, that can be answered there, but I am thinking the following:

6 x 70cc's in a rail powered by your HFS-5 system, this will be done per throttle body.

My RRFPR will be set to 43psi down low and pushing upwards of 70psi at the top. Now my understanding is that my fuel injector duty cycle will not change as i will be using the pressure to add more fuel.

Since I am running a supercharger and not a turbo should I use the MAP pressure switch as opposed to the Fuel injector switch?

If I run MAP, is there a way to vary the flow? So at say 5psi of boost I am only using 60psi line pressure and then at 12+ i goto 125psi line pressure?

I hope this is the correct thread to pose such questions. It seemed fitting.

[Richard L]

The line pressure for the Water injection system seem to be a bit low. Can you re-spring the RRFR ro control betwem 125psi to 150psi? If you lower the line presusre, you will not be getting the correct water flow out of those jets.

The HFS-5 can be triggered by Fuel duty cycler (PWM) for MPS or MSP sensor (0-5V).

YOu can double the flow by feeding the HFS-5 with two injector pulses. cylinder 1 and 4 etc.

[wizegi///m3]

Originally Posted by Richard L

The line pressure for the Water injection system seem to be a bit low. Can you re-spring the RRFR ro control betwem 125psi to 150psi? If you lower the line presusre, you will not be getting the correct water flow out of those jets.

The HFS-5 can be triggered by Fuel duty cycler (PWM) for MPS or MSP sensor (0-5V).

YOu can double the flow by feeding the HFS-5 with two injector pulses. cylinder 1 and 4 etc.

When I was speaking about the 43 - 70 psi I was speaking about my fuel pressure.

My water pressure is set to the default 125psi (may go up to 150 to increase flow).

We are currently planning to control the system via PWM, my concern is that the Fuel duty cycle will not increase as while boost builds the fuel pressure will increase, injecting more fuel, but the duty cycle will not.

So my question is the only way to make it increase water injection follow boost is to use a RRFPR on my HFS-5? I want the system to inject a small amount of water say at 6psi and then increase flow as boost / more fule is used to redline.

Can it vary flow; or once it trips say 50 fuel duty cycle or 6psi boost it starts spraying 420cc's, as opposed to ramping up with fuel / boost curve?

[Richard L]

It will work very well.


The Shurflo pump we supply can run up to 150psi as standard. When you order your RRFPR, make sure the spring is rated to woprk in 100-150psi range. (125psi normal)

Here is a flow curve of the jets:

[wizegi///m3]

Richard.

How do i go about ordering the non bypass fitting for the HFS pump as well as the regulator. Looks like I am in need.

THx

[Richard L]

I have copied and pasted the following from another thread here, try contacting SX. It appeared that they have what you are looking for.



Hi,

As I understand it the SX series of pressure regulators are water/methanol safe --- although the operating range is quoted as 35-90 psi so
they are likely not to be suitable.

The 515 series of fuel lab regulators are also water/methanol safe --- and they quote an operating range up to 125 psi.

Regarding "115psi (@-10psi vac) to 150psi (@25psi boost)" --- as far as I know the presence of water during the compression stroke absorbes heat thus preventing detonation. In the absence of detonation risk i.e. manifold vacuum, water injection reduces peak cylinder pressure.

Given that the available pressure regulators indicate a max water pressure of 125 psi --- I would set the water pressure to 114 psi @ 14 psi boost rising to 125 psi @ 25 psi boost. This is mostly because I experience the onset of detonation at 1 bar and this is where my map starts dumping fuel...

Say what happened to the HFS-5 one time only introductory offer...?

Robert