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Need some input on my Neo build and ITB's

Hi all,

I have done a bit of reading but nothing quite definitive has come of it so I have a few questions to ask to the more experiences fellows out there.

Long story short is.. I am wanting to build up a forged Neo motor on the side with rb26 itb's. I am in no rush as my current motor in my R34 GT-T is just fine (touch wood) so I do have time on my side and I will be doing all the work myself, i have built a few motors before but no rb's yet, this will be my first RB build.

I am really liking the combo of solid head + vct + itb combo so I am trying to determine the most effective and sensible way of doing it.

First question I have is.. Are R33 and R34 blocks the same? I have bought a mint R33 s2 short motor for really cheap which I plan to put 34 neo forged pistons and rods into, a long with a neo head.

Is there any issue with this or are the blocks identical once pistons and rods are taken out of the equation?

Second question, if i want to run ITB's, has anyone had success with an adaptor plate to fit rb26 itbs? Where are they sourced from these days?

As for the turbo side of things, I am leaning towards a gtx3076 on ethanol but I will concentrate on that later.

 

I am fairly certain RB25 vanilla/neo blocks are identical.

Otaku garage sells adapter plates for RB26 plenum onto RB20/25. I just purchased one last week and am waiting on it to be delivered. Can post back with pics of it once I receive it.

With a 25 head though the VCT solenoid needs to be relocated. Check Forge Performance on Facebook, they sell a nice looking adapter kit.

  • Like 1

If I were building an ITB RB engine other than a 26, I would not use RB26 TBs.  They are old, they are famously annoying to get to seal, often requiring a great deal of stuffing around to get them working properly.  Given that you have to go to the expense of buying ITBs and an adapter plate, and then possibly having a leaky piece of shit that won't work until it has emotionally broken you, I can't see the sense in not looking for an alternative using new off the shelf TBs.  I would be thinking of DCOE pattern TBs as a first option, or if the sizing is not helpful, looking at 6 separate TBs.  The only hassle here is linkages and synchronisers, but these are generally available from the same people that make the TBs anyway.

My bro-in-law did this to a 2JZ-GE using TBs from a 20V 4A-GE.  Looks proper good.

  • Like 1
3 hours ago, iruvyouskyrine said:

I am fairly certain RB25 vanilla/neo blocks are identical.

Otaku garage sells adapter plates for RB26 plenum onto RB20/25. I just purchased one last week and am waiting on it to be delivered. Can post back with pics of it once I receive it.

With a 25 head though the VCT solenoid needs to be relocated. Check Forge Performance on Facebook, they sell a nice looking adapter kit.

Thanks mate, I have added them on FB and found the adaptor kit! Pretty well priced.

 

29 minutes ago, GTSBoy said:

If I were building an ITB RB engine other than a 26, I would not use RB26 TBs.  They are old, they are famously annoying to get to seal, often requiring a great deal of stuffing around to get them working properly.  Given that you have to go to the expense of buying ITBs and an adapter plate, and then possibly having a leaky piece of shit that won't work until it has emotionally broken you, I can't see the sense in not looking for an alternative using new off the shelf TBs.  I would be thinking of DCOE pattern TBs as a first option, or if the sizing is not helpful, looking at 6 separate TBs.  The only hassle here is linkages and synchronisers, but these are generally available from the same people that make the TBs anyway.

My bro-in-law did this to a 2JZ-GE using TBs from a 20V 4A-GE.  Looks proper good.

Haha I know where you are coming from, I used to own an R33 GT-R and I made the mistake of cleaning the TB's in the process of installing my PFC DJ ecu and was stuck with 1100rpm idle when I put it all back together.

A bit of tomei throttle paint did the trick though. Honestly If I can get my hands on an itb set for around 300 bucks with the plenum, it makes it very feasible.

3 hours ago, iruvyouskyrine said:


With a 25 head though the VCT solenoid needs to be relocated. Check Forge Performance on Facebook, they sell a nice looking adapter kit.

 

/\ This.

 

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