550 cc Fuel injector for RB25DET

[sidewaymambo]

Hi,

Some of you might know, I am preparing for my R33 modification (check the following link http://forums.skylinesaustralia.com/showth...=&threadid=4696),

however I need your advice; What sort of 550 cc injector for my modification? from I can see someone suggest 13B rotary injector, but does it need a new fuel rail? what can't use RB26 injector? consider cost and effect, what do you suggest?

thanks

[Guest Nismo_Freak]

Word is that the CA18DET accepts the 550cc injectors from the RX7 very well. Since the CA18DET and the Skyline motors both utilize top-feed injectors the 550cc out of the 13B should just drop in. SR20DETs however use the side-feed injectors and are in their own boat.

[sidewaymambo]

I see, it makes sence..

Did anyone done this? and how they perform? thanks..

[2rismo]

Don't they have to be the same impedance as well as fed the same way?

Cheers

[meggala]

yeha the rb25 uses side fen injectors like the sr20 in fact the same injectors . so to use top feed you need a new fuel rail caost around 2-300 to get made up

meggala

[rev210]

550cc are top feed .

RB25DET are SIDE feed.

You will need a new fuel rail my friends.

[Joe]

hardly any1 with a RB25/RB20 has used a RB26DET injectors because of the Impedance difference.

GTR uses Lower OHM compaired to the RB25 (side feed)/RB20 (Top feed)/SR20 (side feed) which are higher.

You can bring down the ohm by buyin a resistor back.

I would suggest to buy some nismo or bosh ones so that go in quiet easy into your car.

[AndyMac]

Depending on the application you may considar the use of GTiR or JDM S15 injectors, which are 470 or 480cc...fit straight in.

Of course this depends on how hard you intend to tune the car.

The Rotary ones require fuel rail mods and a few other setup mods.

A good fuel pressure regulator with the JDM/GTiR injectors would probably work very well.

Or you could go and try get some Sard Injectors off the jap auctio websites, they too fit in, but may require some wiring impedence mods

[Joe]

People usually sell them in a group of 4's

i would imagine it will be a pain in the arse 2 get 6's

if i was to buy a second hand injectors esp. the GTiR ones i would give them a good sonic bath.

[AndyMac]

Valid Point.

I know of four around at the moment off a JDM...

maybe you could buy two off a nissan dealer.

How much are sonic baths and how long do they sit in there for ?

[Joe]

PeakRPM: sorry mate i wouldnt have a clue or even the price of a sonic bath but if i was to buy second hand injectors i will give it a sonic bath, unless i know the owner of the injectors & the conditions.

Im busy playing around with my Power FC :wassup:

[sidewaymambo]

Thanks for all the input..

From the following url, it does confirm SR20DET and Rb25DET use the same injectors, both side feed, but might have long and short difference (not sure what it is? someone got clue?)

http://www.dspeed.co.jp/english/others/mot...er/m_o_inje.htm

[sidewaymambo]

Does anyone know what sort of flow rate fuel pump needs to run 550cc injector on Rb25DET? thanks..

I know people use GTR, however that's say 550cc (per min) x 6 (injectors)x60(mins)=198L, so I will assume 250L will do the job?

[Evan]

Bigger pump = better

Bosch 040, 044 or 975 i think all 3 would do the job. 975 is best buy i think, 044 is better quality and has 2 screw fittings not 1 screw and one barb like the 975 althought the barb is useful if you doing an in tank pump.

E

[MRK25T]

After searching for injectors I came accross this old thread which is relevant to my question.

Today I was at my mechanics asking him how I could get some more power out of me s2 r33 gtst.

He said he would sell me his r33 gtr injectors from his own car and would get them serviced and installed for about 80-100$ each.

He also said he would sell me a fuel pump for about $300 fitted, and lastly he would sell me a fuel pressure regulator for about $160.

All up about $1200.

My aim is to get high 12sec for 1/4mile which he said would be possible with my current mods (turbo back exhaust, hi flow cat, high flowed turbo, pod, FMIC, profec b EBC which will probably be set around the 1bar mark) and a powerFC which will follow after I get fuel right.

Does anyone have suggestions or comments on what i'm planning on doing because i'd love some feedback if i'm making a mistake.

Mark

[meggala]

no need for injecotrs for a high 12

plus the gtr injecotrs wont work on an rb 25 you will need a new fuel rail and they are only 70cc's bigger plus they are the wrong impedance and type they are top feed rb25's are side feed

a bigger fuel pump with adjustable reg and power fc

should give you 220 rwkw plentyof people here have done it

meggala

[MRK25T]

Thanks meggala,

Could you tell me exactly what fuel pump and adjustable reg I should get and maybe ball park figures if you have any.

Mark

[Steve]

MRK25T, you really should think about your management before you start worrying about your fuel. With an aftermarket ecu fitted, and a fuel pressure reg with stock injectors you should be able to push 250rwkw - as I know of someone who is currently at 257rwkw with the stock injectors. The stock ecu thinks you have stock injectors, so if you upgrade your injectors with out the ecu (or an SAFC) you will be running very rich = less power and lots of black smoke.

If you want to go top feed injectors, you will have to replace or modify the stock plenum and then get a new fuel rail. Thing to remeber is that side feed high impedance injectors are bloody expensive - top feed high impedance are reasonably cheap, you can pick up top feed injectors quite readily for approx $75, side feed dont expect much change from $250+.

[MRK25T]

Steve,

I was going to get my car boosted, get the fuel system installed, and get the powerFC installed and tuned at the same time.

I think it will work out cheaper if I get it all done at once instead of staggering it (both in time without the car and money).

My profec B is on its way from Nengun, I now need advice what parts I need now.

Thanks Steve and Meggala

[Steve]

MRK25T, sounds like a good idea getting them all done together, just one other thing you will have to do, and that is get a decent clutch, as your stock one just wont hold, if you've already got one, disregard this post

Steve