rb25 question

[yanay]

hey guys im fairly new to the rb25 motor.. ive had ca18s and ka24ets but this is my first rb. I bought a r32 swapped with a rb25 with wiring problems and blew the stock turbo right out of the gate.. So i have finally finished my mods to fit a Precision 5252e on it. Mods include :
walbro 255
5 bolt downpipe 3" straight piped and dumped behind front wheel
2" screamer pipe
External wastegate
3" intake with stock maf
greddy fmic 2.5" piping.
Just curious if anyone knew with this setup what a fairly safe boost level would be to run..?
How much boost and how much power can i make before i max out these injectors with that turbo? im ordering a wideband for it this weekend
Specs on turbo:
• 59mm inducer compressor wheel
• "E" compressor cover 3.0" inlet/2.0" outlet
• T350, 76 trim turbine wheel
• - T3 .48 or .63 A/R with 5 bolt discharge (without wastegate hole)
• 360° journal bearing system
Thanks in advance. ive searched and cant find anything with my setup that i could really go by..

[h4X6]

well as far as i can see i dont see you having any major fuel mods done like a FPR or bigger injectors/tuned ECU... that being said, i wouldnt boost over 10psi... dont want you to run lean and blow a head gasket or worse....

[yanay]

Yeah thats the plan so far.. just wasnt sure if 10 was to high on it.. im going to order injectors the next week or so but its a dd so i cant have it sit to long

[h4X6]

ya 10 should be ok... if you want, try to get your hands on a wide band O2 sensor and test... if at 10 PSI you are running lean then back it down...

dont forget with bigger injectors your going to see a tune or something to control them... stock ECU sure can handle them but you will be running rich all the time...

[yanay]

yeah when it sees injectors it will see a dyno tune

[Skym]

Stock ECU probably won't be able to handle those mods very well. Being a high compression engine it's very sensitive to the ECU tune being correct (I wouldn't drive it or drive it off boost until get ECU tune). Not sure how many times I've seen photo's of hole in piston due to bad ECU tune with RB25DET.

If wired the fuelpump to receive full voltage from battery via relay, etc, should be richer at mid to high rpm where stock injectors are open more with higher lph fuelpump, stock FPR with small orifice (need an adjustable FPR to drop or raise fuel pressure). Stock is around 135lph and you're running a 255lph fuelpump.

For dyno tune, can use a internally modified (so it plugs into stock loom) 300zx / Z32 ECU with Z32 MAF + Z32 MAF plug + ECU tune.

If have the $$$ Link G4 ECU or ViPEC ECU with MAP sensor, optional parts like IAT sensor, boost control solenoid + ECU tune.

I think you are limited to around 295rwhp with stock injectors. Boost level it reaches will depend on ECU tune, when injectors max out. With bigger lph fuelpump + wiring mod, ECU tune, higher fuelpressure, can extend the hp limit of injectors.

There's a calculator you can use to work out the limit's of injectors when fuel pressure is changed -

http://www.deatschwerks.com/fuel-calculators/