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Hi,

I have a built RB30 going in soon. I have a twin in-tank pump setup.. Although I haven't bought the pumps yet - I plan to run the 1 pump full-time, and stage the 2nd pump under a variable, eg boost/etc.

My question is - Is there a way to monitor the fuel pressure in such a way that if eg either of the 2 pumps fail, it should cause the fuel pressure to drop, and as a result, take preventative measures eg  eng check light + limit boost/kill eng etc.

I will be running a Link G4+ and use an analogue port to drive the 2nd pump. I will also be running a fuel pressure/temp sensor.

Thanks.

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I honestly prefer to PWM the pumps instead of staging them, you'll find with staging pumps there's a momentary spike in fuel pressure each time it's activated.

Not enough to feel a change, but enough for you to see a spike in rail pressure and also makes it harder to get your transient tits.

An elegant way is to PWM both pumps, another way I thought that could be just as elegant is to have one pump on full tilt and the 2nd (or 2nd lot of pumps) running off PWM but with a very low duty and ramp them on based on MAP.

No spikes, fuel won't heat up as fast and low load on your electrical system.

Just an idea :)

 

Yeah +1.  Just setup a new fuel pressure sensor on the FPR going to Link g4+ on my GTR.

Link can do all of the features the upper Haltech's can as far as I know.

All awesome tech.

Edited by Stixbnr32

The ECU outputs PWM, just buy a 100amp solid state relay such as the Jaycar ones. Note they don't have internal suppression so you'll need to run a diode across the inductive load. Also they don't like high frequencies, between 100hz to 200hz is good.

I run mine at 150hz, also use a good heatsink too :)

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  • Like 1

For what it's worth, if you use a G4+ Link ECU with fuel pressure input and use the modelled fuel mode ("VE mode" as people usually call it)  it will automatically factor in spikes or dips in fuel pressure to the fuel calcs and evens things out, but yeah PWM control is win.   

Edited by Lithium
  • Like 2

Also run it in my car via the Link G4+ GTR as well. Have fuel pressure sensor and setup differential pressure to cut once it drops below nominated pressure. Still running 3x 460s full time to lazy to setup staging of 1 or 2 pumps. 

7 hours ago, klutched said:

Also run it in my car via the Link G4+ GTR as well. Have fuel pressure sensor and setup differential pressure to cut once it drops below nominated pressure. Still running 3x 460s full time to lazy to setup staging of 1 or 2 pumps. 

Dam, do you have issues with fuel heating up?

 

22 hours ago, Dose Pipe Sutututu said:

The ECU outputs PWM, just buy a 100amp solid state relay such as the Jaycar ones. Note they don't have internal suppression so you'll need to run a diode across the inductive load. Also they don't like high frequencies, between 100hz to 200hz is good.

I run mine at 150hz, also use a good heatsink too :)

 

 

What ECU are you talking about here sorry? I didn't know the Link G4+ outputs PWM.. I have a few friends who had to buy external PWM controllers.

44 minutes ago, Predator1 said:

What ECU are you talking about here sorry? I didn't know the Link G4+ outputs PWM.. I have a few friends who had to buy external PWM controllers.

Kebabtech, however the Link G4+ would definitely support it.

 

 

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