Jump to content
SAU Community

Recommended Posts

Hi all

I've been vaguely thinking about upgrading my inlet plenum on my rb26/30, and have noticed that 3 or 4 vendors have popped up on ebay recently selling the same or very similar cast alloy inlet plenums for the rb26.

An example is here:

http://cgi.ebay.com.au/EPR-RB26DETT-Intake-Manifold-Plenum-/290513936378?pt=AU_Car_Parts_Accessories&hash=item43a3fadffa

SOme of the listings state straight out they are copied from the greddy one. In addition to having a larger 95mm inlet, they claim to boltup to the factory throttles and have a much larger internal volume.

THe other advantage is, being a matte alloy finish, they don't have the 'cop bait' look about them that some other polished or chromed ones have.

Just wondering if anyone has purchased one of these yet, and had any comments they'd like to share. I'm particularly interested in:

1) ease of fitment - did things more or less line up and seal at critical points where it is supposed to, including machined surfaces and bolt holes

2) any interference - eg does it foul on the clutch m/c like many other upgrade plenums

3) inlet piping - how much of a hassle is it to source an adapter flange

4) performance - did it make any noticeable change in performance (good or bad)?

5) overall assessment - am I better off paying for a hypertune or similar?

There is no market for something like this...

If you want less than say 500rwkw then a standard one is fine, if your getting serious about big top end power there is no reason why you shouldn't be able to afford a genuine Greddy or Hypertune

As above. Couldn't agree more. I can't see how going bigger is going to offer and performance benefit.

Infact I've never seen results to show the GReddy is any better than factory.

The nismo one makes a minor midrange diff, but for the price its really not justified at all.

So what is the key advantage with the hypertune style plenums? Is it the internal trumpets, better shaped runners/plenum, or something else?

I'm going to be retaining the 6-throttle setup, if that makes a difference.

well the nismo and trust plenum both have basically the same principal. they have better air distribution (factory plenum send too much air to cyl 5+6 which causes them to run a bit lean). and they are larger volume. larger volume is basically a benefit to on/off/on throttle response. having a larger volume of air in the plenum before the throttles mean when you crack them open there is plenty of pressure and volume there to fill the head. the better design does increase midrange and response a bit. the nismo one I think is a little better in midrange and the trust one a little better in top end. the hypertune one also seems to be a good design.

as far as the cheap ones go, personally I'd stay away. they are usually so poorly cast it's a joke. all the copy plenums i've seen were ill-fitting and needed plenty of work to fit nicely. for the effort spent you still have an inferior product and it leeches money off the people who spent the R+D to design the thing. the trust ones are not super expensive. nismo ones are a little more so but not too bad used if you can find one.

as far as performance increase don't expect it to do anything magic. i'm running a trust plenum on my 32 with the 2.7 Jun engine and it seems to work fine (with 6 throttle set-up). the car is quite responsive and has great midrange but how much of that is due to the 2.7 and the combo of the cams and 2530s or the tune in the motec or the plenum is anyones guess as the plenum was on it when I bought it.

Fair enough. The issues with quality/fitment are enough to decide this issue from my perspective. There is very limited space to work with around the plenum of a GTR so any issues with fitment will rule out any knockoffs as an option. Also the amount of screwing around required to remove the plenum with the motor in the car means I will be doing it once and doing it right - having to remove it because of leaks or gaskets not sealing etc is not really an option.

It seems as if the genuine greddy ones routinely come up for sale for $900-1000, whereas the hypertune ones are around $2k, so I'll probably go with a greddy one at this stage (together with an r33 clutch m/c).

I have a RB26/30 and can't help to think the larger capacity will be better. The reduced velocity from the larger intake should also aid better cylinder distribution. The gains due to the butterflies being after the Plenum are not the same as other plenums however. The linkages on the 6 throttle OEM have to be lengthened by 10mm or so. There should be enough adjusment available to do so. Not sure about clearance from the brake lines on the master cylinder. For the money, I will eventually give it a try. The Casting on there is much better than the Rb25 ones.

Matt

lol, do it. fatz is pretty drunk most of the time so there's a 50/50 chance he'll give you the genuine greddy one for $150... :) worth the gamble I say.

ps your engine bay will be tight as all hell now. 6 boost taking up all the real-estage on the ex side and trust plenum is bloody huuuge on the inlet side, plus the fact you've got a 30 in there. you will never get a hand down in there again!!!

my thing is tight enough now with just 2530s with the same HKS piping you have and hks manifolds and a trust plenum and it's a standard block jun 2.7.... I had to move my PS res too but it's actually a good thing as it takes it further away from the turbo heat. mines now up near the passenger headlight and radiator support.

Actually I reckon the rb30 block sitting the head, and therefore the plenum, up slightly higher would improve access to the lower plenum bolts, and give more hand-space in the critical area which is between the transfer case and the underside of the plenum.

Or knowing my luck it makes it worse, more than likely its the latter.

ps your engine bay will be tight as all hell now. 6 boost taking up all the real-estage on the ex side and trust plenum is bloody huuuge on the inlet side, plus the fact you've got a 30 in there. you will never get a hand down in there again!!!

my thing is tight enough now with just 2530s with the same HKS piping you have and hks manifolds and a trust plenum and it's a standard block jun 2.7.... I had to move my PS res too but it's actually a good thing as it takes it further away from the turbo heat. mines now up near the passenger headlight and radiator support.

I have to move my PS tank aswell. What did you use for the lines?

Actually I reckon the rb30 block sitting the head, and therefore the plenum, up slightly higher would improve access to the lower plenum bolts, and give more hand-space in the critical area which is between the transfer case and the underside of the plenum.

Or knowing my luck it makes it worse, more than likely its the latter.

Yep ,oil filter is easier to get to aswell.

Matt

as best I can remember it's still using the stock ones. just moved. it;s still about the same distance from the PS pump just different place (now near headlight). I'll have a look. there's only low pres line anyway from res to pump so it's quite easy to change.

  • 2 weeks later...

hmmm.... dosn't look all that much different to my genuine greddy unit.

bugger!

It'll be interesting to see if there are any gains/losses.

I'm so happy your doing all the testing on alot of parts I'm planning to use shortly. I just won't be going 3lt... stroker for meee :thumbsup: and a little (mm maybe alot) of giggle gas.

Cheers

Justin

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Also, I logged some data from the ECU for each session (mostly oil pressures and various temps, but also speed, revs etc, can't believe I forgot accelerator position). The Ecutek data loads nicely to datazap, I got good data from sessions 2, 3 and 4: https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-2?log=0&data=7 https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-3?log=0&data=6 https://datazap.me/u/duncanhandleyhgeconsultingcomau/250813-wakefield-session-4?log=0&data=6 Each session is cut into 3 files but loaded together, you can change between them in the top left. As the test sessions are mostly about the car, not me, I basically start by checking the oil pressure (good, or at least consistent all day). These have an electrically controlled oil pump which targets 25psi(!) at low load and 50 at high. I'm running a much thicker oil than recommended by nissan (they said 0w20, I'm running 10w40) so its a little higher. The main thing is that it doesn't drop too far, eg in the long left hand fish hook, or under brakes so I know I'm not getting oil surge. Good start. Then Oil and Coolant temp, plus intercooler and intake temps, like this: Keeping in mind ambient was about 5o at session 2, I'd say the oil temp is good. The coolant temp as OK but a big worry for hot days (it was getting to 110 back in Feb when it was 35o) so I need to keep addressing that. The water to air intercooler is working totally backwards where we get 5o air in the intake, squish/warm it in the turbos (unknown temp) then run it through the intercoolers which are say 65o max in this case, then the result is 20o air into the engine......the day was too atypical to draw a conclusion on that I think, in the united states of freedom they do a lot of upsizing the intercooler and heat exchanger cores to get those temps down but they were OK this time. The other interesting (but not concerning) part for me was the turbo speed vs boost graph: I circled an example from the main straight. With the tune boost peaks at around 18psi but it deliberately drops to about 14psi at redline because the turbos are tiny - they choke at high revs and just create more heat than power if you run them hard all the way. But you can also see the turbo speed at the same time; it raises from about 180,000rpm to 210,000rpm which the boost falls....imagine the turbine speed if they held 18psi to redline. The wastegates are electrically controlled so there is a heap of logic about boost target, actual boost, delta etc etc but it all seems to work well
    • hahah when youtube subscribers are faster than my updates here. Yes some vid from the day is up, here:  Note that as with all track day videos it is boring watching after the bloopers at the start.  The off was a genuine surprise to me, I've literally done a thousand laps around the place and I've never had instability there; basically it rolled into oversteer, slipped, gripped and spat me out. On the way off I mowed down one of the instructor's cones and it sat there all day looking at me with accusing cone eyes as I drove past. 1:13:20 was my fastest lap, and it was in the second session, 3rd lap.  It (or me!) got slower throughout the day as it got hotter.      
    • It sounds like you want what the Toyota Landcruisers have for their roof racks. Wanna know what you end up with? Rust holes in the roof, and water everywhere...
    • Discovered today that if I select reverse first and take my foot off the brake, then select drive, the drive indicator light works and so does the tiptronic gear indicator. 
    • Ok so after much research and talking with knowledgeable people I've got my turbo conversion done and it's all running great other than 1 small issue.  Car has remained auto with the na auto and tcm, I've used a stagea ecu with. NIstune board and everything is great other than my gear selection on the dash. It illuminates park, reverse, neutral, 3rd and 2nd. But nothing drive or what gear your in when you pop it into tiptronic.  I'm sure there is maybe 1 wire in the ecu plug I need to move to rectify this. Does anyone here have any ideas?   Cheers guys
×
×
  • Create New...