Rb26 Inlet Manifold And Adaptation To Rb25 Heads .

[discopotato03]

Just starting a new thread on this topic .

If this becomes an affordable mod to do what problems can people see when making it all work and run in say an R33 GTST .

Firstly I suppose the 26 plenum has to physically clear anything that can't easily be moved because it gets spaced out maybe 20mm ?

Then I suppose its wiring everything up and allowing for water and air plumbing . I guess you'd also have to make sure the three main passages between the head and manifold were adequate to avoid temperature differences along a long I6 head .

One problem SK mentioned that may be an issue is where the injector tips are aimed with the manifold now 20 odd mm away from the head . I think it would be a fiddly job to weld up the injector bosses and re-machine them at a slightly shallower angle .

Other than these issues it has the potential to allow far less restrictive throttling and warmer cams before things get too choppy . The obvious one is of course intercooler plumbing which would now be virtually as per GTR .

The burning question would be is it more practical just to run an RB26 head and be done with it .

Thoughts ? Cheers A .

[bubba]

I'm going to be running stock runners and the GTR plenum bit (no multiple throttles). IAC valve along with most/all of the vacuum connections hidden on the underside.

I don't envisage too many problems other than welding and plumbing. This *should* cost less than half of what making a full custom plenum myself would costand without the need to R&D things, let alone off-the-shelf items..

I am doing this for clearance reasons with the new turbo.

Would appreciate any input other than "that sucks" or "it's not going to work".

[The Mafia]

In doing this, I would only be interested in throttle response. I love the way GTR's respond.

I'd need an apadter plate though, and the downside is there is someone trying to sell an australian version for $750. Thats just a stupid price. I have seen adapters on yahoo auctions for around the $350 mark.

Someone is getting greedy.

[dano4127]

Just FYI there is a SAU Vic car (Red 32) in latest autosalon magazine using the RB26 setup on 25 head

[FineLine]

In doing this, I would only be interested in throttle response. I love the way GTR's respond.

I'd need an apadter plate though, and the downside is there is someone trying to sell an australian version for $750. Thats just a stupid price. I have seen adapters on yahoo auctions for around the $350 mark.

Someone is getting greedy.

You seriously have no idea. Just the development cost alone would frighten most off.

I anticipated it selling for less than the stated price too but after seeing what is involved and the quality of the end product its worth every damn cent.

[R31Nismoid]

Just FYI there is a SAU Vic car (Red 32) in latest autosalon magazine using the RB26 setup on 25 head

Yeah Adam's car is running the Blitz adaptor from memory

[The Mafia]

You seriously have no idea. Just the development cost alone would frighten most off.

I anticipated it selling for less than the stated price too but after seeing what is involved and the quality of the end product its worth every damn cent.

Actually, I have every idea.

Two of my good mates, one a Boiler maker, and one a fitter looked into it with me.

Couple of cad drawings later, and a chat to their mate that can laser cut metal, and it was going to be done quite easily, and cheaply.

I just got slack for making the "vaccum box" etc and getting it all together.

Wouldn't have been a hard process at all. Its comments like these that make me wish I had of not slacked off and just done it.

Edited February 28, 2008 by The Mafia

[Duncan]

sorry I don't think the price is greedy. considering design, materials, whatever they use to cut them and the low volume.....might cost more than poor fitting chinese ones but they often are not worth the trouble

[Adriano]

Actually, I have every idea.

Two of my good mates, one a Boiler maker, and one a fitter looked into it with me.

Couple of cad drawings later, and a chat to their mate that can laser cut metal, and it was going to be done quite easily, and cheaply.

I just got slack for making the "vaccum box" etc and getting it all together.

Wouldn't have been a hard process at all. Its comments like these that make me wish I had of not slacked off and just done it.

Cummon Jono, if you spenty less time on here, you would probably have it done by now.

[Kaido_RR]

blitz no longer make there kit which can cause a problem if you just buy the adopter plate, as the genuine blitz kit came with afew other things,

like: AAC valve adapter kit; so you can run the GTR AAC valve.

In the pass week i have had a friend in japan get incontact with URAS and blitz asking about the kit, URAS does not make the kit and advised us to called blitz, blitz no longer make the kit

another place that could get it was http://www.ricohracing.com/ , but now there website doesn't work anymore and we couldn't get incontact with them

Edited February 28, 2008 by [Michael]

[FineLine]

Actually, I have every idea.

Two of my good mates, one a Boiler maker, and one a fitter looked into it with me.

Couple of cad drawings later, and a chat to their mate that can laser cut metal, and it was going to be done quite easily, and cheaply.

I just got slack for making the "vaccum box" etc and getting it all together.

Wouldn't have been a hard process at all. Its comments like these that make me wish I had of not slacked off and just done it.

And my wifes brothers cousins sisters uncles dog was "GUNNA" do it too.

The difference is, these people "DID" do it and did it darn well. And until you have done it you are blowing smoke.

[R33S2]

I have a duel trade as a Fitter and also a Boilermaker and i have been involvled in alot of R&D for customers, what you dont realise is that big companies can write off their R&D in tax, for a little guy to gear up for a small volume product with none of the breaks that a big company gets makes it more expensive, if you and your mates can wack one together for less than that go ahead and post up the detailed drawing so I can make one for bugger all.

[Rhinorebel]

Well, seeing as how I am the guinea pig for this adaptor plate, I think it is a very good piece of workmanship and considering all the relevant factors, fairly cheap. I looked for the Blitz version and all the tiny bits of available info on it and it didn't impress me and wasn't available. The design and manufacture of the one I am getting was brilliant and a combined effort of a couple of people, one of which is selling the end product. We should have results within a week and I will be more than forthcoming with the results. Have a look at the pictures and don't be too quick to judge.

[GTRgeoff]

I've looked at all the alternatives and short of a 26 Head this is the most elegant option. A welded plate would be the cheapest and would allow 25 injectors. The wiring and piping is easy.

Don't even consider this for a 20 head. The velocities are going to be very slow through the runners for that capacity and would be a backward step.

As for the production costs for the local option, sounds fair to me having done a fair amount of NC machining and production work, but if Jono were to do it for zero profit I'm sure he would be popular for a while... but the price would soon go up dealing with sales, production, startup costs, warranties, insurance.......

[R31Nismoid]

What about RB25 front facing options like trust (greddy) etc?

[Roy]

Actually, I have every idea.

Two of my good mates, one a Boiler maker, and one a fitter looked into it with me.

Couple of cad drawings later, and a chat to their mate that can laser cut metal, and it was going to be done quite easily, and cheaply.

I just got slack for making the "vaccum box" etc and getting it all together.

Wouldn't have been a hard process at all. Its comments like these that make me wish I had of not slacked off and just done it.

Seriously! I dont doubt you spoke with your friends from those trades. But i expect like every guy from those sorts of trades employed by others they dont appreciate the final cost. For instance the programming time of said laser cutting is a one off for each run. (they may do it chaper for subsequent batches), for a piece like this im guessing at best $200...more like $350. Now the more pieces made the more that cost can be spread accross other units. But its a cost that must be absorbed.

Then on top of the programming time you have to pay for materials, and the actual laser cutting... plus all the other issues that since you have looked at this you will know cause other complications. On top of that couriers from delivery of materials, delivery to laser cutters and back etc etc.

I have done a bit of work towards these adaptors (ie a lots of work myself) and the hurdle is noone will pay the price unless i get it done OS. I considered gettting Bass Junky to use his international manufacturing contacts to do this...but guess what? That has more issues with regard to quality control and having to handle all the warranty claims for a period as you no longer have direct control of manufacturing etc etc, shipping taxes...etc. If i was a business someone else mentioned that i can offset some costs against R&D tax concessions

So...i dont doubt your boiler maker mate and your other fitter and turner mate think its easy...but i think you are wrong in saying the price being thrown around is high. Maybe poor value?!?!? Ok argue that point. But the dollar value isnt far off for a locally manufactured product that is run in low volumes.

But, feel free to actually go ahead and follow through and reap the rewards if you think you can do it cheaper for the masses and still look after your own interestes

[Rhinorebel]

What about RB25 front facing options like trust (greddy) etc?

The single throttle body feeding from the front has been known to starve the rear cylinders and the response is also a factor. Plus I got a 26 plenum and throttle bodies very cheap and wanted to see if it could be done. I am undertaking a full-on rebuild and wanted to try a few things. As I said, I should have it on the dyno by the middle of next week and on the road by the weekend hopefully.

[The Mafia]

And my wifes brothers cousins sisters uncles dog was "GUNNA" do it too.

The difference is, these people "DID" do it and did it darn well. And until you have done it you are blowing smoke.

over 3000 posts in less than a year. I'm sure you're a very constructive person.

Its funny how a select few are quick to knock my claims on the head.. Even though I've always come through with everything else I have done. Don't pass me off as some bullshitter on this forum, I've got better things to do than lie.

I had 2 Adapter plates laser cut for my turbine housing to manifold, to space it out. Cost me a Bottle of Jim Beam, to get 2 cut. I look after my friends, and they look after me.

I had a RB26 Intake manifold and 6 x throttle bodies, we did up some drawings on what was needed, how it would bolt to the head, how you would make the "vacuum box" for all of the vacuum reliant systems etc. It wasn't hard.

Then My boilermaker mate, the person that tigged up every bit of pipe on my car (no, I have NEVER been to a shop to have custom stuff done) said it would be much easier to maybe tig up some RB25 runners onto a plate and bolt the 6 x throttle bodies onto that plate. Once again, that plate would be laser cut.

So its not that hard when you think of other ways to do it.

If you don't believe me, here is some of his work, and even some pictures of him working.

Fineline, just for you and your smart assed rant.

And back on topic about throttle bodies:

My boilermaker friend designed this from scratch, he wanted more response, and had two RB25 Throttle bodies spare. Took a bit to get the tune set to balance two of these, but it worked very well. Oh, and those raised cam covers he made himself too. Very talented guy. Some of his work is unbelievable.

Everyone else out there - the idea of going 6 TBs is awesome, and don't think that you have to go and spend too much money getting an adapter plate. Do what we were thinking of doing besides the adapter plate, and cut some runners from the RB25 and make your own plate that will bolt onto the RB26 TBs.

Edited February 28, 2008 by The Mafia

[Kaido_RR]

hmm interesting read

my main problem is using gtr injectors and the ACC valve. i can source the adopter plate from japan (quality is very good) and won't have a problem sending it out to one of you guys to copy. but i have the issue of wiring up the gtr injectors and the getting the ACC valve to work.

in the end i don't think it will work out cheaper than the greedy opinion but i am in preference to the 6 throttles. I'm also very interested to see if the gain are for real, as alot of Japanese mag claim 20-40hp increase and an increase in responds. BUT i have also read that responds under 3000rpm is decreased i can't remember if this is what blitz stated or if it was in a Japaneses mag.

Also at the same time, i am considering buying a NISMO plenum and putting that on at the same time, weather or not it will make a huge different will be interesting to see also

edit: i just had alook at the pdf file i had from blitz about the tip, and it also mention that there is issue with the idle senors, i would be interested if someone has a digram of the rb26 plenum and rb25 to compare where each item is (digram from the owners book or fast program)

ALSO LETS TRY AND KEEP ON TOPIC

Edited February 28, 2008 by [Michael]

[FineLine]

over 3000 posts in less than a year. I'm sure you're a very constructive person.

Its funny how a select few are quick to knock my claims on the head.. Even though I've always come through with everything else I have done. Don't pass me off as some bullshitter on this forum, I've got better things to do than lie.

I had 2 Adapter plates laser cut for my turbine housing to manifold, to space it out. Cost me a Bottle of Jim Beam, to get 2 cut. I look after my friends, and they look after me.

I had a RB26 Intake manifold and 6 x throttle bodies, we did up some drawings on what was needed, how it would bolt to the head, how you would make the "vacuum box" for all of the vacuum reliant systems etc. It wasn't hard.

Then My boilermaker mate, the person that tigged up every bit of pipe on my car (no, I have NEVER been to a shop to have custom stuff done) said it would be much easier to maybe tig up some RB25 runners onto a plate and bolt the 6 x throttle bodies onto that plate. Once again, that plate would be laser cut.

So its not that hard when you think of other ways to do it.

If you don't believe me, here is some of his work, and even some pictures of him working.

Fineline, just for you and your smart assed rant.

And back on topic about throttle bodies:

My boilermaker friend designed this from scratch, he wanted more response, and had two RB25 Throttle bodies spare. Took a bit to get the tune set to balance two of these, but it worked very well. Oh, and those raised cam covers he made himself too. Very talented guy. Some of his work is unbelievableWould you like to see pictures of my wifes brotyhers cousins sisters uncles dog. The adaptor plates he was "GUNNA" turn out are unbelievable.

Everyone else out there - the idea of going 6 TBs is awesome, and don't think that you have to go and spend too much money getting an adapter plate. Do what we were thinking of doing besides the adapter plate, and cut some runners from the RB25 and make your own plate that will bolt onto the RB26 TBs.