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Hiya ... I'm swapping a VQ37 into a BMW and am curious about the fuel system design from factory.

I understand its a return-less system with regulator in the tank with the pump set to 51psi. Does this have a vacuum reference running all the way back from the motor / inlet manifold to the regulator or is it set statically ? Is the fuel pump always on or modulated on/off or voltage changed by the ECU ?

In the USDM 370Z / G37 service manuals i can see a line running from engine to regulator in tank but it does not go into what this is.

I'll be looking to convert to a return system (as the BMW is) with filter and regulator in the engine bay but want to know if I need to vacuum reference it or not and if the fuel pump can be wired 'traditionally' so it will be always running via the return system. Will also need to add the fuel temp sensor which is used on the VQ also it seems.

G'day Mate, no Vacuum reference, fuel pump is always on. When using an aftermarket pump, just use the factory fuel pump + wire to switch a relay for pump supply.

Here's a vid on my youtube channel showing setting up fuel return & the fuel pump wiring I did as a part of my TT Build 

 

  • Like 1

Awesome thanks Trevor !! Watched your video and like the look of the CJ kit for regulator implementation without altering the fuel rails so I think this method will suit me very well also.

Did you make the solution yourself or do they provide this as a kit ? This looks like the tap fitting, at that point its hose and fittings + reg I guess !! https://cj-motorsports.com/products/fuel-tap-npt-2-bolt

Yes, I have the full CJM  fuel return Kit, I think this is the fitting here. https://cj-motorsports.com/products/fuel-tap-4-way-2-bolt it gives you fuel in, fuel out to the Rails , by pass to the reg  then back to tank & Gauge Port.

Cheers Mate.

Edited by mycarhasposessedme

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