Rb26 Inlet Manifold And Adaptation To Rb25 Heads .

[shanef]

what are the benefits of retaining the VCT? and is it as simple as removing that section of the gtr plenuming and welding the gts-t part on?

only benefit i see is cost. i.e it costs a fair amount to change to a solid lifter/cam setup. but then you have a huge selection of cams to chose from

i dont really want to go explaining exactly what needs to be done on the open forum, however purchasers will be told exactly what to do and whats needed

[Kaido_RR]

only benefit i see is cost. i.e it costs a fair amount to change to a solid lifter/cam setup. but then you have a huge selection of cams to chose from

i dont really want to go explaining exactly what needs to be done on the open forum, however purchasers will be told exactly what to do and whats needed

thanks for the reply

i understand not wanting to make everything public

If my j-spec supplier doesn't work out i will be getting in contact with you for sure

again thanks for all the helpfully reply

Edited March 11, 2008 by [Michael]

[R31 drift pig]

Wouldnt recomend the rb26 set up on a 20 head.

Why? Not enough airflow?

Shane and I have spoken a bit about making one for the 20..... Im hoping this isnt an exercise in money wasting....

Edited March 11, 2008 by R31 drift pig

[GTRgeoff]

That's right, not enough airflow for it to make decent response and stumbling on throttle openings. The velocities of the air are what is important. But for the cost, just setup a custom 6tb intake.

Call Wayne at Meridian Motorsport in Melbourne. He can either organise the setup or put you in touch with someone who can.

[FineLine]

I guess if you wanted to go to the extreme you could reduce the size of the throttle body to match the engine size.

Could turn out to be a true response weapon that way.

[R31 drift pig]

going to be a big ask with the Trust TD06 going on in a week or two. Now Im really confsued as to what to do.

Dang

[dano4127]

That's right, not enough airflow for it to make decent response and stumbling on throttle openings. The velocities of the air are what is important. But for the cost, just setup a custom 6tb intake.

why is there not enough air flow? cause the 20 heads have smaller ports?

[GTRgeoff]

Smaller ports and smaller capacity.

Do some quick volumetric flow rates on how much air alone goes through and the differences will be massive.

[StealthZ]

Been lurking for a bit, but now I am finally in the position to get some wk done to the car. I am very interested in the ITB conversion for my (RB25) RB30DET. Is there any (signiciant) difference in ITB designs throughout the RB26 year models that I should be looking for? I have done a search, but came up empty handed.

I already have the Greddy intake with the Q45 TB, but on my '77 280Z that manifold angles out too far and for the most part hits the fender. The GTR manifold would pretty much perfectly line up with the openings in the rad support to the FMIC. Plus the extra throttle response wouldn't suck either...

[Kaido_RR]

through i give an update on my situation.

After searching long and hard i finally found a brand new Blitz Kit (found on yahoo auction) price was too good to pass up

my gtr plenum comes this week and hopfully the blitz kit will be here within 5-6days. i put some pics up of the kit once it arrive

[Kaido_RR]

does anyone know if you can run the rb25 fuel rail and injectors with the rb26 plenum?

[shanef]

does anyone know if you can run the rb25 fuel rail and injectors with the rb26 plenum?

nope you cant

[Sydneykid]

I have done the sums many times for many people, no matter how I work it it ALWAYS works out cheaper to sell the RB25 cylinder head and excessories and buy an RB26 cylinder head. By the time you do the inlet manifiold, cams (RB26 cams are always cheaper), pulleys, bypass the VVT, lifters, valve springs, valves and then injectors (top feed are always cheaper), the fuel rail (the standard RB26 rail is good for over 650 bhp) etc etc.

Then you have the fact that the end result (of a hybrid RB25 cylinder head) is never as good a full RB26 top end.

Cheers

Gary

[TTT]

thought this might be of interest for someone in here...

http://www.skylinesaustralia.com/forums/in...t&p=3699871

R32 GTR Inlet Manifold - $50

Has had black paint removed, ready for painting, no weird markings etc good condition

[bubba]

Mine cost me $100, it's just the plenum (like the post linked above), not t/b's etc.

[Wobbz]

I havent looked at the 26 plenums in detail... but couldn't you just plane off say 5mm from the first components that bolt to the head (do the throttles bolt directly up to the head on a 26?? I had a feeling they have a small manifold piece between the head and throts...), and get a 25 flange laser cut out of ally, and weld onto the planed off area? That would seem like the most simple, and cheapest method to me... mind you, i haven't looked at the 26 and 25 inlets in detail...

Laser cutting ally is cheap as... hell, take the laser cutters a new gasket for a 25 and they'll be able to cut you an ally flange piece of piss... (ie. used as the stencil)... it might cost you what... $100-150? maybe less (for the flange)... welding it would be the more expensive part, but even that should only cost a couple hundred at most... (welding + grinding the inside ports clean)

Maybe im heading off on the wrong track here, but I just haven't had time to look at the two inlets in detail...

[shanef]

you'll find with anything lasercut, it will bend as the material isnt clamped down on the bed

[TTT]

I have done the sums many times for many people, no matter how I work it it ALWAYS works out cheaper to sell the RB25 cylinder head and excessories and buy an RB26 cylinder head.

Cheers

Gary

You mean like this??

http://www.skylinesaustralia.com/forums/R3...-E-t207769.html

[bubba]

I havent looked at the 26 plenums in detail... but couldn't you just plane off say 5mm from the first components that bolt to the head (do the throttles bolt directly up to the head on a 26?? I had a feeling they have a small manifold piece between the head and throts...), and get a 25 flange laser cut out of ally, and weld onto the planed off area? That would seem like the most simple, and cheapest method to me... mind you, i haven't looked at the 26 and 25 inlets in detail...

Laser cutting ally is cheap as... hell, take the laser cutters a new gasket for a 25 and they'll be able to cut you an ally flange piece of piss... (ie. used as the stencil)... it might cost you what... $100-150? maybe less (for the flange)... welding it would be the more expensive part, but even that should only cost a couple hundred at most... (welding + grinding the inside ports clean)

Maybe im heading off on the wrong track here, but I just haven't had time to look at the two inlets in detail...

I'm going single throttle body with the GTR plenum welded to stock runners, hopefully it turns out alright

[GTRgeoff]

That's a head setup worth grabbing. 1800 with freight say. A little skim and lap the valves and bingo, bolt right on. Covers and all. Might just grab it myself.