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HI Guys

i put a Adjustable Fuel Press regulator in my R33 Rb25DET

pleasse let me know if someone has experience..

need pressure for stock injectors...

but i will put 550cc in next week i have to change the pressure

THX alot Dino

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Do you really need a FPR?

Putting in larger injectors is the best way to fix fuel issues, but you can just use the stock reg, nothing wrong with it at all.

I did with my setup/740cc injectors and ran over 350rwkw, and many others have done that.

Stock rail pressure is around 37psi if i recall.

i already put it in. i just had one on stock and put it in ..... lol

so i can leave it at 27psi with 550cc?

dino

Do you really need a FPR?

Putting in larger injectors is the best way to fix fuel issues, but you can just use the stock reg, nothing wrong with it at all.

I did with my setup/740cc injectors and ran over 350rwkw, and many others have done that.

Stock rail pressure is around 37psi if i recall.

Yes, you can use the stock fuel reg.

There is no need to up the rail pressure unless you are running out, which with 550cc's would be decent power

no need for another FPR. just make sure u have a decent fuel pump and leave the injectors unless ur pushing the 300rwkw mark or driving it on the track.

no need for another FPR. just make sure u have a decent fuel pump and leave the injectors unless ur pushing the 300rwkw mark or driving it on the track.

but remember that increasing fuel pressure is not only to get more out of your injectors, important fact to mention that it does increase fuel atomisation which causes a more uniform burn which inturn produces better torque. also increasing fuel pressure will reduce injector duty cycle, its not recommended running ur injectors over 80% (although many do) ive seen melted wiring and failed injector drivers in heavy competition. At 80% 550cc injectors will be good for around 420hp at a pressure of 43.5psi which is what most injectors are calculated at.

but remember that increasing fuel pressure is not only to get more out of your injectors, important fact to mention that it does increase fuel atomisation which causes a more uniform burn which inturn produces better torque. also increasing fuel pressure will reduce injector duty cycle, its not recommended running ur injectors over 80% (although many do) ive seen melted wiring and failed injector drivers in heavy competition. At 80% 550cc injectors will be good for around 420hp at a pressure of 43.5psi which is what most injectors are calculated at.

For a street driven car I see no point if ur running say 250. I ran stockies for a while running about 260 and they did get over 85% but its only for a short time and doesn't happen often (with a 040 pump). I personally have 550cc ones in mine, they dont get much over 70%. generally sit at 40-45%...

when they were stock...they average d about 65% makes sense...so unless u have a need i dont see the point. Spend the 600 bucks on something else.

However if u want a FPR...just get the NISMO replacement one...its good I heard and is a direct replacement.

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