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R33 Rb25det not performing

New to the forums not really sure if this is the right section to be posting in but I've spent several hours raiding the forums and can't find a solution anywhere.

I have an r33 rb25det it has a bigger fuel pump, front mount intercooler, super spark coils pack, 3.5" turbo back exhuast and a boost tee. It's running 0.74 bar of boost but it feels like it's not even boosting I can hear the turbo working and the gauges are reading 0.74 bar of boost. It smells like it's running real rich and has recently started to really chew through fuel. I have changed the spark plugs had them gapped correctly and the coil packs are 2 months old. What could be causing it to feel like it's not on boost and being real slow? 

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Get a wideband, and a fuel pressure gauge, actually these should already be in your car.

They help immensely when troubleshooting as you can drive down the road and help determine things like fuel filter, fuel pump, ignition issues etc. You can also see if your fuel pressure correlates with an issue in AFR, if they don't match than it could be an issue ECU/vaccum side. Rather than just opening the hood and looking for issue that can't be seen.

Get a tune. My rb25 drove like crap with similar mods, most 25s don't like to be changed from stock unless you get them tuned.
Question has been asked plenty of times, and it will come back to one thing. Tune!!

Maybe check the fuel lines on the pump didnt get confused, not sure on skyline pump but happened to me on a falcon and the vapor line got confused with the return line.  Long term result is now piston slap..

If the fuel pump is the walbro 430lph then that is most of your problem. Try running less boost (0.6 bar), cleaning the maf, check for vacuum leaks, etc.


But if the fuel pump is too big the regulator won't be able to adjust the pressure low enough.

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