Issues Fitting 1/2 Height Injectors (1300, 1550, 1700, 2000, etc.) with Extenders to RB25 NEO Intake Manifolds

[Dose Pipe Sutututu]

Image Credits: Injector Online (www.injectorsonline.com) - go buy shit from them, good prices and fast delivery!

So yeah - I'm actually stuck and need everyone's thoughts and opinions!

Long story short, I know RB25DET NEO plenums like to take 3/4 height top feed injectors, which are approximately 52~55cm o-ring to o-ring in distance. Most will just get a set of 1000cc Bosch injectors OR modified Bosch 1250cc injectors that are of that length. I wanted more fuel supply, so opted for the non-modified Bosch 1550cc (1650cc often advertised) injectors.

These injectors are 1/2 height, and are approximately 40mm o-ring to o-ring in distance, with the correct extension you can make these the same height as your typical 3/4 height Bosch 1000cc or XSpurt 1000cc injector. Below is the same injector now with the extension, giving you that 3/4 height.

Theoretically they now should just bolt up and off you go right? Many sites from various countries tend to advertise 1/2 height injectors with extensions (making them 3/4 height injectors) as direct fit - however here's the fun part, you actually can't even get the injector to go all the way into the injector seat on the RB25DET NEO intake manifold.

They simply just don't work! Problem is, as they are so short before the hard plastic that keeps the o-ring captive doesn't even touch the injector seating area of the intake manifold because the injector plug ends up touching the intake manifold. Being the person that at times thinks outside the box, I went on and installed a bunch of 14mmx5.5mm injector buffers from a GT-R thinking that would solve the problem. 

Well - it kind of did, now there's a bit of space and the injectors are somewhat sealing well... but yes, now the connectors won't even go on! because there's simply not enough room. So I am really intrigued how these different suppliers are all listing these injectors as direct fit - when clearly they won't? (noting all the injectors are 1/2 height with either full height or 3/4 height extensions)

https://www.injectorsonline.com/au/1500cc-xspurt-injectors-x-6-neo.html

https://www.golebysparts.com.au/parts/view/2053/58/nissan-rb20-25-26/fuel-rails-and-fuel-rail-injector-kits/rb25-r34-neo-plazmaman-fuel-rail-kit-2000cc-injectors

https://www.ebay.com.au/itm/Nissan-1300cc-Fuel-injectors-RB25DET-NEO-R34-Skyline-Stagea-C34-Plug-Play/182639648111?epid=6004139375&hash=item2a862bdd6f:g:S~QAAOSw4DJYlreh

https://www.ebay.com.au/itm/Bosch-2200cc-Flow-Matched-Injector-Set-For-Nissan-Skyline-R33-I6-RB25-Neo/222702641007?hash=item33da1c9f6f:g:u9wAAOSw0exZ-oq3

So the question, how did you guys with 2000/2200cc Bosch CNG or ID1050/1300/1700 injectors get them on? considering they are all 1/2 height and all require to be extended? I would assume all the plugs would hit the same region and would disrupt how the injector would be seated. And FWIW, I'm using a Plazmaman rail (still, doesn't affect how the connects sit and/or hit the intake).

(yes I even changed extenders so they're identical to the Xspurt kit, I sourced my injectors elsewhere though) 

Also you can't really rotate the plugs upwards because the injectors no longer will seal properly.

My ultimate last option is to go install a R33 intake manifold on my R34 NEO motor (which I don't want to do).

Thanks all!

[GTSBoy]

Die grinder?

[Dose Pipe Sutututu]

Funny you said that, I was tempted to grind a bit off the injector connectors so they can clear the top area of the intake manifold.

I more curious to hear/see how guys with NEO motors fit those old 2000/2200 gaysex injectors back in the days as they're all 1/2 height also and 100% would have the same issues.

[Dose Pipe Sutututu]

Some digging around it seems guys with BRZ/86 FA20DI N/A motors actually have the same issue but ID have come up with a solution for them.

I am pretty sure it won't fit inside the RB25 NEO intake manifold 

[NEO25T]

Hmmm, this shows size difference on the xspurt webpage.

 

I asked Scotty about this so hopefully he has some info that will help out

[Dose Pipe Sutututu]

These are my photos, which shows an identical injector setup as per Injector Online.

So you can see that the connector hits the intake manifold, and yes it's possible to turn some of them to allow the injector to be seated in however that means some injectors won't be perpendicular to the manifold (big no no). To make things more fun you also won't be able to get the connectors on lol.

The best and probably only option I have is some form of 14mm to 14mm (male to female) injector seat as such.

I've simulated this using the 1/2 to full length extension (hole is too small I know haha)

[Dose Pipe Sutututu]

15 minutes ago, NEO25T said:

Hmmm, this shows size difference on the xspurt webpage.

 

I asked Scotty about this so hopefully he has some info that will help out

Unfortunately you can't get high capacity unmodified injectors in 3/4 height. If you look closely at those tips of the Xspurt 3/4 height they have been milled off.

I've spent decent coin on these unmodified Bosch 1550cc injectors and I do want to run them.

I'm still super curious how people with ID1050/1300/1700X injectors are getting them to fit on NEO motors and also how people with the Bosch 2000/2200 CNG injectors got them to fit. There seems to be zero guides or images for these setups.

My very last options are to either go back to a R33 intake manifold (gay) or buy a Hypertune (over priced) or equivalent plenum such as Otaku Garage/Madcat (China dim sim sui mai spec). 

[Dobz]

It would be good to know how much meat is on the manifold before it breaks through to the coolant gallery. You might be able to make enough clearance for the plug by removing aluminum.

[GTSBoy]

1 hour ago, Dobz said:

It would be good to know how much meat is on the manifold before it breaks through to the coolant gallery. You might be able to make enough clearance for the plug by removing aluminum.

 

12 hours ago, GTSBoy said:

Die grinder?

 

[Ben C34]

I would just go full retard with a die grinder       Grind everything. The manifold. The plug. The injector. Grindr.  make it fit in the hole.  

[Griffin]

Not sure what all the fuss is about, i have your answer....

 

 

 

 

 

 

 

 

[Dose Pipe Sutututu]

maybe convert to carbies, easier

[GTSBoy]

2 hours ago, Ben C34 said:

I would just go full retard with a die grinder       Grind everything. The manifold. The plug. The injector. Grindr.  make it fit in the hole.  

Ben!  Look at your PMs, goddammnit.

[discopotato03]

I had a close look at a Neo turbo and R33 lower inlet manifold sections and they are quite different in the injector mount area particularly at the manifold face . The Neo puts the injector tip closer to the head than the R33s and doesn't have the recess around the injector tip area at the top of the manifold ports .

Also the ribbed water log is further outwards from the manifold face on the Neo manifold . I'd say this is why the injectors sit deeper into the manifold on the Neo .

I think the sad truth is that unless you can fettle enough out of the manifold without finding air or water to get clearance those short EV14 injectors may not be usable .

Next question may be will the full length injectors work and are they available in a suitable size unmodified ? 

[NEO25T]

This is my one with a standard injector just to have a look.

An unmodified 1600cc 65mm injector would be perfect ?, although i couldnt find anything

[Dose Pipe Sutututu]

Bad news - after a few e-mails back and forth with Injector Online they too agree that what they have listed is incorrect and they are removing it soon.

TL;DR Do no try and fit 1/2 Height Injectors to a R34 GT-t NEO Intake Manifold, they WILL NOT WORK!

There are plenty of INCORRECT listings all over the web.

[NEO25T]

2 hours ago, Dose Pipe Sutututu said:

Bad news - after a few e-mails back and forth with Injector Online they too agree that what they have listed is incorrect and they are removing it soon.

TL;DR Do no try and fit 1/2 Height Injectors to a R34 GT-t NEO Intake Manifold, they WILL NOT WORK!

There are plenty of INCORRECT listings all over the web.

Whats your plan now Johnny?

[Dose Pipe Sutututu]

Might slap on the R33 RB25 intake manifold onto the motor OR hope someone knocks on my door takes the car/motor/spare parts and gives me a stock 335i F30 BMW.

[NEO25T]

Well good luck with that lol

Im going to wait for magic to happen and use the xspurt 1550 injectors in the neo manifold ?

[discopotato03]

There may be a slight fix depending on how much material you can mill off the manifold face of the Neo lower section .

I had a look at the face and a problem is the lack of material around the front water inlet . This would limit how much you can machine off without enlarging this water passage .

If you are prepared to work around this and reset the injector height in the mounting hole it may just be enough to clear everything for your short EV14s .

A .