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I am going to go for 300rwkw (maybe 290) on my 260rs stagea and want to see if i can retain the stock injectors I have read that with a FPR it will get me there, now that wont be run constantly I will just have that on a squirt every now and then on a cool night. But I know the rule of thumb is 1hp for every cc so 440hp, I read that 500cc is possible with fpr and dont run them over 85% duty?? also I wanna know if I can run a wire direct from the battery to my fuel pump with a relay and not upgrade to the bosch 040?? So its a 33 GTR pump. Yes I have upgraded the turbos and will be doing the afm to Z32 items as well.

Thanks

Edited by cefiro

85% duty will need 75psi base fuel pressure from 43.5 -Pump is rated to 75psi so once you start boosting it will be past its limit

90% duty will need 65psi base -That will give you 10psi boost to play with.

95% duty will need 59psi -That will give you 16psi boost to play with.

All at 300rwkw

well if you don't do track days or go to the drags very often, and drive reasonably sensibly on the street then you should get decent engine life using the stock injectors. it is only going to be at high rpm at 100% throttle where the injectors are going to be running out of capacity. so even boosting it round the streets, as long as you aren't taking it to redline every gear change it should be fine.

at the end of the day, as long as the injectors aren't maxing out it will be like any other injectors. your engine will only go boom if it isn't getting enough fuel. if the stock injectors start to make it run lean because they are getting blocked, then if you had 1000cc injectors in there and they started to get blocked then either way there isn't going to be enough fuel going into the engine. the ecu tells the injector how long to fire for. if it isn't flowing as much as the ecu thinks it is (no matter what size injector you have) it is going to run lean.

just get your injectors properly cleaned so you know they are going to work at their best. good luck. i'm all for people that like to push the limits and be different.

I am going to go for 300rwkw (maybe 290) on my 260rs stagea and want to see if i can retain the stock injectors I have read that with a FPR it will get me there, now that wont be run constantly I will just have that on a squirt every now and then on a cool night. But I know the rule of thumb is 1hp for every cc so 440hp, I read that 500cc is possible with fpr and dont run them over 85% duty?? also I wanna know if I can run a wire direct from the battery to my fuel pump with a relay and not upgrade to the bosch 040?? So its a 33 GTR pump. Yes I have upgraded the turbos and will be doing the afm to Z32 items as well.

Thanks

I have read that stock injectors can get about 350rwkw, so that must mean you should be fine mate.

good luck

I have read that stock injectors can get about 350rwkw, so that must mean you should be fine mate.

good luck

you should have said something to make out you were joking... You sound half serious in that post lol

Stock rail pressure + stock injectors seems to be considered ok up to ~280, so 300 with some more rail pressure seems reasonable. Just make sure your tuner is more focussed on providing a safe tune rather than a particular power level, ie ask him to get as close as he can to 300 but keep it convervative.

you should have said something to make out you were joking... You sound half serious in that post lol

damn you for giving me away :) after all i have done for you!

I thought he was serious:S

How long have you been a internet mechanic for ?

At the end of the day it goes like this.

Yes you can run 200psi rail pressure, nearly blow your injectors out of the rail.

You get your 300rwkw, sick! how good is that? you go on the net and you tell everyone "i got 300 with stock injectors ner ner ner ner"

But what you don't tell everyone ??

Lets see, your mrs plugs in her 12v hair straigtner, it has a issue, your fuel pump is not getting a full 14 volts anymore, your pump starts to flow less fuel hence the injectors are not getting 200psi rail pressure.

You switch your head lights on, your pump is not pushing 200psi rail pressure no more

your running a little low on fuel, your fuel surges.... ohhh nasty

your altinator decides its not going to work very good anymore, ohhh snap

you get a lean out, you break a $6000 rb26.

ALL SO YOU CAN JUST SAVE $800.

FFS!! do the job properly. or sell your car because you CANNOT afford it.

Seriously, your car runs top feed injectors you have access to the cheapest injectors on the market, others have to spend a extra $500 for side feeds and they still go ahead and do the upgrade because they know that every internet mechanic out there can claim 350rwkw out of stock injectors, how many times? once ? twice? on the third time the engine explodes.

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