Stock FPR good enough?

[87supramario]

Hey guys, I was just wondering if the stock 1jz FPR and rail would be fine for the application I have. I have a 650cc injectors with 650cc tuned stealth ecu, T78 turbo, planning on running a single Denso TT pump with stock lines and V12 mod. Do I need to upgrade the stock fuel pressure regulator?

I'm no wizz when it comes up upgrading the fuel system, I'll admit lol :nono: Any help would be greatly appreciated.

-Mario

 

[Kai]

With that setup i'm surprised you haven't leaned out your mixture and turned your combustion chamber into a plasma cutter. The 650cc injectors you have now - what pressure do they actually hit 650cc/min AT? Stock FPR isn't going to supply anywhere near enough pressure for them.

Best to just get an AFPR and set it up, properly. IIRC, Driftmotion still supplies kits for the JZ.

 

[Dan_Gyoba]

You lean out the mixture when the fuel pump can't keep up to demand at pressure. If the pump is upgraded and your FPR can't keep up, what you get are pressure spikes when the FPR isn't letting enough fuel return to the tank.

So, what we need to know is what you've done on the other side to make sure that your fuel supply can keep up with demand, particularly when you hit high boost pressures. This is the hardest on the system, because it requires the greatest fuel pressure, and the greatest flow at the same time.

I would strongly recommend that you upgrade the fuel pump. The Mk4 Denso pump (which you mentioned) at the very least, and if you're going to be pushing those 650cc injectors at all, possibly a dual pump setup. once you do that, an upgraded FPR is almost certainly going to be a necessity.