RB25 GReddy Plenum, who's fitted one?

[PHaT MR30]

Hey i just bought one of these yesterday and awaiting its arrival. Now i know there is much discussion as to the questionability to if its better than the std plenum, if the flow pattern is better or worse etc etc

i didn't buy it for a power increase or anything like that, i simply bought it to make my intercooler piping simple and to give me more under bonnet space (plenum and inlet pipe were very close to bonnet) and it will now allow me to fit a strut brace.

im just looking around for other ppl's that have put one on to see how much is involved, where do all the vacuum hose and stuff go and the water lines etc?

i think i will also get an XF falcon throttlebody as i have heard that going from 3" (intercooler) to 2 1/2" (throttle body) to 3" (inlet of plenum) can cause alot of turbulence.

ive also bought a matching fuel rail, which i am hoping doesn't have a regulator on it as i am using a malpassi.

any help would be great!

cheers

tim

[YO880]

Tim,

how did you go with this?

i am looking at buying a greddy plenum too, and am wondering the same thing, i assume as it is specifically for GTST then most of the pipes etc should be easily relocated, but i am not sure about what throttle body to use or how easy it is to replace.

[Guilt-Toy]

Why would you buy one when the standard plenum is good for 550hp ? appart from the different location yeah

[YO880]

exactly that, it is going into an old c110 skyline, and i will have very little height for the TB and intercooler pipe across the top of the engine (plus i have no room to cross back the intercooler pipe to the left side). probably should have gone for an Rb26

[PHaT MR30]

http://www.livesockets.com/quoc/rb/

this website was very helpful, although i have been lazy and not fitted mine yet, it has made me understand whats going on.

i ended up buying a Q45 (VH45DE) throttlebody as it bolts straight up and is a big 90mm sucker.

originally the water line ran from the back of the block, through the throttle body, and back into that spot next to where the thermostat housing is.

So I think the propper way would be to place it there.

Edited December 14, 2005 by PHaT MR30

[YO880]

thanks for the link phat, very usefull!

appreciate your response, i have opted to go the Q45 TB route too..

[Ronin 09]

"Croat" may be able to verify, but I understand that the XF bolt pattern does not match the Greddy manifold - requires mods to fit...

I ran a Q45 on mine when I had a 33, had hunting issues with idle though

[PHaT MR30]

XF isn't 'that' much bigger than std anyway and its bolt patter is smaller (work that out), i wouldn't waste my time with one of them old things now anyway, i got my Q45 for about $150 delivered from japland.

hunting issues? were you using the VH45 AFM too? i heard a few ppl have that problem, maybe a defective TPS? im getting weird signals from doing some test with a multimeter on mine, and im not sure which plug to use?

[PHaT MR30]

Fuel rail and TB fitted

TB

sorry crap quality, it was on my phone

[YO880]

I pulled the stock intake plenum and trial fitted the greddy today, looks very nice

the stock rail does not seem to fit up to the plenum, as the fuel lines hit the plenum.

i assume that you are using the greddy fuel rail?

Is the greddy 11mm fuel rail top feed? and is the 10.5mm one still side feed (it says it is for std injectors)

if i get the 11mm one, do you need to use greddy injectors or can any be used? and do you need a collar to fit the injectors?

where does the FPR mount on your rail or do you have to rig it up somehow?

thanks

Kent

[YO880]

here is the page out of the greddy manual, can anyone translate?

[B33st]

I just installed my greddy plenum last week and the original fuel rail went on fine i just had to take off the solid fuel lines. I'm going to get some new ones made to go into their place..

Im not sure about the greddy fuel rails being side feed, the one in the photo above is a top feed rail.

With the FPR on mine i was probably just going to stick with the original one on the end of the stock rail, though i do also have a billet SX FPR that i am considering putting on in line with the standard one and just mounting it on the side of the engine bay some where.

If you went with an aftermarket rail like the greddy one pictured you would also need to mount the FPR off the side of the engine bay somewhere.

leigh.

Edited January 4, 2006 by B33st

[PHaT MR30]

i opted for the std size fuel rail and have just bunged GTR injectors in there (top feed). no collar is required, however you need the GTR insulators as the RB25 ones are too big (you will see the two different sized cut outs in the injector seats on the plenum).

you can use std rail and there is two option, both in the manual, one looks messy and shit and the other neat.

[PHaT MR30]

[Sydneykid]

i opted for the std size fuel rail and have just bunged GTR injectors in there

Be careful with the impedance, GTR injectors are low impedance (3-4 ohms) and RB25 injectors are high impedance (12-14 ohms).

cheers

Edited January 5, 2006 by Sydneykid

[Roy]

Fuel rail and TB fitted

<{POST_SNAPBACK}>

Can i ask where you got the fuel rail from, and how much? It looks like a single feed

[ylwgtr2]

its a trust rail roy

[YO880]

it seems that from what i can find out about the greddy rails from nengun and greenline, there are 2 versions..

one is an 10.5mm, which is meant for the std plenum i assume, and the 2nd is an 11mm one, for the greddy plenum.. does this measurement relate to the height of the rail from the plenum (some sites seem to refer to it as a diameter), ie. the height of the spacers that are supplied in the kit?

phat, could you please measure the spacers in your kit for me? you got the 10.5mm one?

i am going to use 600cc Nismo GTR injectors

sorry for all the Q's!, i have checked through the documents i got with the plenum, but i can not read japanese and can only rely on what i can make out from the pictures. i am trying to get the instructions translated though

[PHaT MR30]

Bought the rail from Nengun with the Plenum was sfa to buy.

i can't measure it cos im about 100km from home right now organising a charity fundraiser cruise for youth suicide prevention but will do next week when i get home.

i assumed the 10.5 and 11mm one is the difference in diameter of the injector feed. as the spacers are easily 60+mm long

Sydneykid: to your disgust i am not running factory ecu (how much i would love to have a PowerFC, but alas i have a microtech). which can handle the impedence of the GTR injectors.

[YO880]

i picked up my 600cc nismo GTR injectors last night, i measured the injector inputs, and the only thing i could measure that was 10.5mm is the OD of the little o-ring on the injector feed, is this correct?

I also tried placing an injector into the greddy rail, they seem to fit, but obviously i need the GTR insulator you mentioned

i found the following in another post, is the rear insulator the correct part?

R32 GTR / RB26DETT

Rear O-ring - 16412F - $9.50

Rear Insulator - 16603F - $13.35

Front seal - 16603G - $5.35