Jump to content
SAU Community

Recommended Posts

Im using top feed injectors in a rb25det (side rail) inlet plenum.

Ive had a few problems making power and im chasing up any potential issues.

http://www.skylinesaustralia.com/forums/Rb...l=missing+100kw

One that has come up is the injectors dont sit deep enough into the flow causing inefective atomisation.

Has anyone else come accross this?

Please post pic of yr setup.

cheers rob.

Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/
Share on other sites

or get a top feed rail to suit the injectors?

Im curious how you fitted top feed injectors into a side feed rail? You must have modified the crap out of the rail?!?!

he didnt, pic from his other thread - top feed rail.

http://www.skylinesaustralia.com/forums/in...t&id=144591

i dont think that the injectors being set back into the open in each runner would cost you 100kw from low atomisation.

Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/#findComment-3884170
Share on other sites

http://www.skylinesaustralia.com/forums/in...t&id=144591

i dont think that the injectors being set back into the open in each runner would cost you 100kw from low atomisation.

Chasing up any and all possiblites at this stage...

If injectors spraying onto the walls and dribbling into the cyclinders then I would assume that would make a huge differance to combustion???

why dont you sell the top feed, then buy some side feed injectors that are suited to your rail. Problem solved?

Looking into it... but will have to find injectors and plugs, and new fuel rail then modify to suit my fuel system etc

will be easier and cheaper to mount mine a little better. just after a few ideas on how other people have done it...

cheers rob

Edited by roba
Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/#findComment-3884631
Share on other sites

Roba - you know how far in teh injectors sit into the runners?

i did see a post with pics regarding the injectors and how far recessed they are from the air path.

your looking at up to 60psi of rail pressure, unless you injectors arent pointing directly into the air stream i dont see how it would dripple down to the inlet valves.

have you checked that the injectors are perpendicular to the injector hole face?

Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/#findComment-3884844
Share on other sites

Im running rx7 550cc top feeds in a side feed manifold. You need to get an 18.5mm (what i had on hand) drill bit and drill out the holes for the injectors.

From memory i nearly drilled right through, it does not matter if you do tho. Then you can push the injector further into the manifold. the stock o-rings will not fall in as they are like 30mm. With the manifold off you can see the pintle of the injector is just sticking out a mm or 2 into the flow.

I did this after i saw a mate with same setup as yours, under boost the o-rings were moving up the bottom of the injectors and i thought there was potential for fuel and boost to leak

Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/#findComment-3898904
Share on other sites

  • 1 month later...

Im using the rb25de intake and have top feed gtst rail (r32) and top feed injectors but they dont want to fit into the rail as the o ring seems to fat. Can i replace the o rings or does it just take a lot of work to squeeze them in there? The 25de ones pull straight out relatively easily though...... any advice??????

Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/#findComment-4008962
Share on other sites

put the 25de o-rings on the new injectors. Or buy some new o-rings from nissan, i have rx7 550cc and with rb20 o-rings on them they are still really tight in the rb20 rail. I lubed them up a little with a little bit of new engine oil and made sure i didnt pinch the o-rings when i out them into the rail.

Once they are in, you can pressurise the rail to 60psi and they wont fall out!

Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/#findComment-4009998
Share on other sites

Um no good, tried swapping the injector o rings but they still wont fit at the rail or the plenum.

May have to sell and buy something else. Any suggestions or offers for replacement injectors?

The current ones are 670cc's so nothin smaller than 650 i suppose. Have to be top feed.

Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/#findComment-4013489
Share on other sites

yeah they must be they are only a fraction too big. Could i get the fuel rail and runners machined to fit them or is it better to just get different injectors. Had a look on trademe and the other sard injectors to suit gtrs have 14mm o rings top and bottom.....

Anyone who has top mount injectors to fit 20det/25de intake setup around the 6/700cc mark for sale please message me.

Link to comment
https://www.sau.com.au/forums/topic/220085-injector-setup/#findComment-4017842
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • LOL.... a good amount of people (not all) on that continent seem to know everything and like to measure things in bananas, football fields, statue of liberties instead of the metric system lol.
    • I assume the modules are similar enough, so if you've had no issues I don't see why I would. I have tried to find a wiring diagram for the FPCM / fuel pump circuit, but I can't find it anywhere. Otherwise, I would just do some wire cutting and joining at the FPCM and give the 12 V supplied to the FPCM directly to the pump instead. If you know anyone that could help with wiring diagrams, I'd be very happy  
    • If it dies, then bypass. The task isn't difficult. I have one running on a standard R32 FPCM. That's after nearly 20 years of it running an 040, which pull substantially more current than the Walbro. They're not the same module, but I'd hope it indicates that the R33 one should be man enough for the job. I think people kill them when putting proper sized pumps on them, not these little toy pumps we're talking about here.
    • Silicone spray won't hurt anything. And if it does, that's an opportunity to put some solid steel spherical bushings in, so you can really learn what suspension noise sounds like, If you're going to try it, just spray one bush at a time, so you can work out which one is actually noisy. My best guess is that if the noise started only since putting the coilovers in, then it is just noise being transmitted up through the top mounts of the struts, and not necessarily "new" noise from bushes. But it's almost impossible to know.
    • Are you saying the 34 is SUV height, and not that we're talking about an SUV here? (because if we're talking about an SUV, you don't fix them. You just replace them when something breaks. Not worth establishing sufficient emotional connection with an SUV to warrant doing any work on one). I wouldn't jack my car up on a short little loop of 10mm steel rod poking out through a hole in the bumper bar, front or rear end. I realise that we're probably not talking about that type of loop at the front, being the one under/behind the bar on a Skyline.... but even for that one, trying to jack up on what amounts to a thin piece of steel, designed purely for withstanding a horizontal tension force, not a vertical compressive force (and so would be prone to buckling/crushing) and, my most particular bitch about it - located RIGHT AT THE EXTREME FRONT OF THE CAR, applying a load up through the radiator support panel, etc, with almost the entire mass of the car cantilevered between there and the rear wheels? Nope. Not doing that. Not on the regular. That structure out there in front of the front crossmember is not designed to carry load in the vertical direction. Not really designed to carry any load at all, really. The chassis rail that the tow point is connected to would be fine loaded in tension, as per towing. Not intended to carry the mass of the whole car, especially loaded all on one rail, with twisting and all sorts of shitty load distribution going on. No, I will happily drive up on some pieces of wood, thanks. That can only happen on driven wheels, and they are at the other end of the car, and this problem does not exist at that end of the car. And even then, I have been known to drive up on at least 1x piece of 2x8 each side at the rear, simply to reduce the amount of jack pumping necessary to get the car up high enough for the jack stands. What really really shits me about Skylines is the lack of decent places for chassis stands at either end of the car. You'd think they'd be designed into the crossmembers.
×
×
  • Create New...