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Hi I am new to the site, and am currently working on a S13 240sx with an RB25 R34 NEO engine swap. Due to my turbo placement and intercooler piping setup i bought a Greddy "style" intake manifold. My question is what have others done to use the NEO's top feed style injectors with the Greddy style manifold. I made a bracket to physically relocate the fuel rail but there is considerable slop between the injector and the injector bung walls on the manifold. Looking for some ideas as to what others have done to make this combination work

OR....

Are there any cheap alternatives in terms of fuel rails or easy to source stock injectors from other models that may fit (keeping budget friendly in mind haha) I am in the states so r33 injectors and fuel rails dont pop up too often for sale.

Thank you! I have spent a lot of time searching for the answer but not a specific solution other than many people buying new rails and aftermarket injectors. Thanks!!

Edited by getslideways

I just got NEO fuel rail mounts rewelded to a position suitable for Greddy manifold. Costed ~20$.

Do you have any pics? If so it would be greatly appreciated! Also what did you end up using for injector o-rings/sealing rings? Thanks!

I made a bracket to relocate and space the NEO fuel rail and injectors that seems like it will work (still curious to see yours) but now need to make a good seal between the NEO injectors and the inside the intake manifold injector bung somehow, since there seems to be some slop and not air tight

thanks!

Edited by getslideways

or gtr rail and spacers. Use the rb25 rubber seals in manifold or get adapters.

http://www.skylinesaustralia.com/forums/topic/306527-r33-greddy-inlet-plenum-onto-a-rb25det-neo/page__hl__greddy+inlet+neo__st__20

I have done this conversion on my neo

Read my last post, item no.6

Edited by darrinspencer

Hey Darrin,

so theres no aftermarket fuel rails out there to accept the GTT/Stagea injectors?

i wanna do this but dont want to change my injectors.

When I set my imitation greddy manifold on my neo motor, I fitted factory gtt injectors and rail, by slotting the holes in the rail, and making a spacer. and got new O-rings that had thicker sidewalls. Fitted tight. cost 5 dollars from a local bearing supplier. Just make sure if you do do this they're up to withstanding fuel.

Hey Darrin,

so theres no aftermarket fuel rails out there to accept the GTT/Stagea injectors?

i wanna do this but dont want to change my injectors.

The aftermarket fuel rail (cheap chinese HKS copy) fits the injectors.

What the OP was asking was how to fit the neo injectors in the greddy manifold as the greddy is made for R33 side feed injectors.

All you do is keep the standard O ring on the bottom of the injector plus add the R33/S15 larger grommets to fill the manifold.

As long as you have enough clampping pressure on the rail they will seal

Status posted some pic's on here somewhere showing a close up.

The aftermarket fuel rail (cheap chinese HKS copy) fits the injectors.

What the OP was asking was how to fit the neo injectors in the greddy manifold as the greddy is made for R33 side feed injectors.

All you do is keep the standard O ring on the bottom of the injector plus add the R33/S15 larger grommets to fill the manifold.

As long as you have enough clampping pressure on the rail they will seal

Status posted some pic's on here somewhere showing a close up.

Cheers for that,

so these would fit my neo motor? Some say " Single entry single return configuration", my rail has 2 regs, can i still use both regs

http://cgi.ebay.com/ebaymotors/R32-R33-R34-GTS-BILLET-INJECTOR-FUEL-RAIL-RB25DET-RB25-_W0QQcmdZViewItemQQhashZitem3363e700ebQQitemZ220719415531QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Cheers for that,

so these would fit my neo motor? Some say " Single entry single return configuration", my rail has 2 regs, can i still use both regs

http://cgi.ebay.com/ebaymotors/R32-R33-R34-GTS-BILLET-INJECTOR-FUEL-RAIL-RB25DET-RB25-_W0QQcmdZViewItemQQhashZitem3363e700ebQQitemZ220719415531QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

That is exactly what I used, but I did away with twin factory reg's and fitted a Sard one, even thuo I did not really need and adjustable one with the siemen 650cc injectors I used.

Just be away of the cheap copies. I had fuel leaking from both ends and had to get the end re machined square to seal.

I may just have got a dud one which is not unusual for cheap chinese crap.

Can buy genuine HKS but $300++

Do you have any pics? If so it would be greatly appreciated! Also what did you end up using for injector o-rings/sealing rings? Thanks!

I made a bracket to relocate and space the NEO fuel rail and injectors that seems like it will work (still curious to see yours) but now need to make a good seal between the NEO injectors and the inside the intake manifold injector bung somehow, since there seems to be some slop and not air tight

thanks!

Sorry for delay, didn't see your message.

I used slightly fatter than factory lower o-rings + some kind of hard rubber for bigger manifold o-rings, I don't know how to properly call this part. Installation is somewhat messy, but there is no vacuum/boost leak, so it all works for me. I'm currently using factory injectors, so I didn't use any spacer for a rail.

As for pics, I'll try to arrange that in a week.

Edited by Legionnaire

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