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I've picked up a Nismo FPR, in an attempt to squeeze another 10% or so out of my rb20 injectors, and hopefully pull around 200-210rwkw with my highflow.

Just wondering if there is anyway to adjust it .. without having a proper fuel pressure gauge?? I thought there might have been some markings on there, but doesn't appear to be anything like that unfortunately :D

If not, I guess I will leave it to the tuner to do. Its a 5 minute job.. I am just worried I could get charged $50 for labour to fit it!

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I got one of these fitted to my car 2 months ago, and was charged something close to fiddy bucks for labor (good thing I had some other things fitted at the same time!) I thought it was something best left for a tuner to do. As far as I could tell, to adjust it you need to turn the nut on the end? No way you could safely do it with out some sort of gauge though.

"My cat's breath smells like cat food."

So if I bought a FPR with a gauge on it... adjustment would be a piece of cake? Provided you knew what you were doing of course...

What's the difference between a normal FPR and a Rising Rate FPR? What is the optimal setting of this thing?

if you are going for more power than the stock injectors require my advice is to just get bigger injectors. the problem with upping the fuel pressure is that you can cause problems with the spray pattern and in extreme cases cause the injectors to leak. another very common one is that with the extra pressure you can find some leaks will surface in your fuel system.

for example say stock pressure is 38psi with only atmospheric pressure. and stock boost is 7psi that's 45 psi total

now you want to run 4 psi more more pressure. this is 42 psi. and of course with the new turbo you are running 18psi. you now have 60psi at full boost. the difference between 45psi and 60psi is 15psi... that is a lot and i would think is more than the stock system is designed to handle.

OK Mr Beer Baron - thanks for you help.

I'm hoping to chase at least 250rwkw and if possible, 300... perhaps you could PM me a list of parts that would get me to that mark? Also, tell me what the best turbo would be for my application :)

well i'm by far an expert on anything (especially RB25s!) but if i were doing it i'd have (for 300rwkw):

600cc injectors

Power FC

some form of boost controller (personaly, greddy profec B II)

FMIC

upgraded panel filter, or pod

larger exhaust from turbo to tip (3inch should do it)

Oil cooler

decent clutch

as for turbo i'm not to sure what the gun combo is on an RB25 but i think an HKS 2835 kit could be pretty close to the money.

Now just to keep this on topic. Predator, you'll need two things to adjust the reg.

1. workshop manual (to find out what pressure it should run as stock base pressure)

2. Fuel pressure gauge.

other than that a 10mm spanner is the only too required to set it. but just heed my warning about upping base pressure, and upping boost.

Thanks BB, since I drive an Auto does this mean I can scrap the clutch and the power fc?

Could you take a look at my site and tell me what else is needed? I really appreciate your help :(

Now I'm going to stop invading predator's topic :(

Think I'll leave it to the tuner if there is no easy way.. to buy a gauge will cost more than $50 for them to fit and fiddle with it :(

in my case, the rb20 is coming out in about 3 months, so no point stuffing with injectors or aftermarket ECU.. I just want to try and crack a low 13 on the cheap before the engine comes out..

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