Jump to content
SAU Community

Recommended Posts

has any1 modded or purchesed a custom plemun or modded there existing plenum that actually looks anygood

i have seen modded and custom plenums but im not happy with the look of em.

i would like to mod the existing 1 preferably.

any 1 that has done it or no anything good and bad bout it, info would be much appreciated

:)

Link to comment
https://www.sau.com.au/forums/topic/23809-rb-custom-plenums/
Share on other sites

Originally posted by Rb20_4valve

i would like to mod the existing 1 preferably.

that's bad news

they're designed the way they are in order to capture/disperse the air equally

when you move the inlet to the front (I take it this is what you mean?) then you aren't getting equal quantities of air into each cylinder

best way to go if you have to mod your plenum is get some engineered plenum (with the scoops etc) like a sub zero one, or get a brand name one as they've done the work already and have proven results (as far as I'm aware anyway!)

I'd jsut stay with the stock one and increase the tb size, as I read somewhere the other day they have better torque producing figures than the gtr plenum at high revs/boost

Although at the same time I could be talking bs, but that's what I remember

Link to comment
https://www.sau.com.au/forums/topic/23809-rb-custom-plenums/#findComment-509561
Share on other sites

My mate can make a custom plenum on the existing intake runners. Looks very nice, and some of the cars running them have made 400rwhp+, so they work aswell. If you want details then PM me.

I agree that the cut and shut plenums seem like a bad idea, but I have seen a few that still seem to make good power.

Link to comment
https://www.sau.com.au/forums/topic/23809-rb-custom-plenums/#findComment-509607
Share on other sites

Originally posted by PSIKO

that's bad news

they're designed the way they are in order to capture/disperse the air equally

when you move the inlet to the front (I take it this is what you mean?) then you aren't getting equal quantities of air into each cylinder

The stock plenum has had sweet bugger all engineering into dispersing air evenly. It may do, somewhat, but thats more a matter orf course than design. Nissan's target was to lower the cost of ic piping and shorten its route. That they suceeded at, at the cost of an undersized 'cooler, but even air disperstion was not at the top of their list.

I should take pictures of the stock one I have lying around here. The throttle body is positioned such that it blasts air right down the neck of cylinder 3 and 4. No deflectors or trick engineering gone into it at all. I'd be willing to wager that cylinder 3 and 4 running lean is the cause for a substantional number of rebuilds.

Properly done, a cut'n'shut should have no problems out doing the stock plenums job, just have to take it to someone who has experience with it. If you're still sceptical, consider the number of oem plenums that are front facing log-on-top-of-runner styles: ca18det, sr20det, 4g63, 1jz and 2jz. All very similar to what a cut'n'shut ends up being (especially the last two).

The proof is in the works though and Steve-SST has given mine a thumbs up, so it'll interesting to see how it'll fair.

Link to comment
https://www.sau.com.au/forums/topic/23809-rb-custom-plenums/#findComment-511560
Share on other sites

how much for the rb25 tb's? will need one soon for a custom plenum, making it myself with the help of a fabricator so will see how it goes, shoudl save me the 600 he normally charges for this sorta work

also does using a larger tb require aftermarket manangemnt or can i use the safc to clean up the mixtures...

Link to comment
https://www.sau.com.au/forums/topic/23809-rb-custom-plenums/#findComment-516480
Share on other sites

DCIEVE, I was going to sell it for $60 on another forum but you can have a SAU discount :). $50. Pic here.

As long as you can mate your current throttle position sensor onto the new throttle body, you shouldn't have many problems with the ecu recognizing the tb. Fueling might be an issue though and a s-afc won't be as good as a remap.

Link to comment
https://www.sau.com.au/forums/topic/23809-rb-custom-plenums/#findComment-516489
Share on other sites

Originally posted by Gradenko

I should take pictures of the stock one I have lying around here.

In reply to myself, I finally got a pic taken. Not all that clear though. I was holding the plenum "steady" and the half a dozen beers I had before hand had some say in that.

Thats looking down the throttle mounting plate. The light you can see through there is coming in the through the entrance for runner 3 & 4, which is just off the top of the frame. So what happens to air thats blasting in there at 1-odd bar? Some of it hits the runner divider and scatters, but the rest, the majority, takes the path of least resistance to low pressure goodness and ends up in cylinder 3 and 4.

Horrible design.

Link to comment
https://www.sau.com.au/forums/topic/23809-rb-custom-plenums/#findComment-516500
Share on other sites

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

    • Hi 🙋‍♂️. Just bought my Unicorn but the interior need some minor work so it would match my expectations ;). I noticed it is hard to get used oem floor mats in good condition so i started to dig if there's any chance to buy set of new ones. I found two websites - nengun and amayama and it looks like one can still buy factory new floor mats in Japan, but thers a small issue. Some mats (i assume genuine, oem ones) are marked as G4900 and these are "discontinued". The ones you can buy are marked as G4911 but i have no idea if these are also oem, made by other producer or some lower quality replacements that looks entirely different. Can anyone help? 😃  P.s. there is also some strange indication - 0V005, 0V015 and 0V505. Any idea what does it mean? Would appreciate any help with this 🙏
    • Hi, Marek here 🙋‍♂️. I finally fulfilled my longtime dream - recently bought Stagea and now waiting for it to arrive in Poland. There's only few of these in my country, and one of the owners  recommended mi this forum as a source of all the info i'd need since now i own one  so here i am.  
    • Version 1 aluminium airbox is.......not acceptable No pics as I "didn't like the look.....alot" Even after all my "CAD", and measurements, the leg near the fusebox just didn't sit right as it ended up about 10mm long and made the angle of the dangle look wrong, the height was a little short as well, meh, I wasn't that confident that Version 1 was going to be an instant winner I might give Version 2 another go, there's plenty of aluminium at work, but, after having in on and off a few times, and laying in the old OEM airbox without the new pod filter and MAF, there may be an option to modify the OEM air box and still use the Autoexe front cover and filter.... maybe This >  Needs to fit in here, but using the panel, and not the pod, the MAF will need to fit in the airbox though> I'm thinking as the old OEM box and Autoexe cover that is sitting in the shed is just sitting around doing nothing, and they are relatively abundant and cheap to replace if I mess it up and need another, it may well fit with some modifications to how the Autoexe brackets mounts to the rad support, and some dremiling to move it get in there, should give me some more room for activities, as I don't want to move the MAF and affect the tune Sealing the hole it requires to stick it in the air box is simple, a tight fit and some pinch weld will seal it up tight  I am calling this a later problem though
    • and it ends up being already priced in as though you're just on 91RON without any ethanol. Car will lose a bit of economy as the short and long term fuel trims bring down the AFR back to stoich or whatever it is for cruise/idle for the engine.  
    • Oh, you are right. But, in Australia E10 is based on 91RON fuel and ends up being 94RON. Hence it being the cheaper option for economy cars. The more performance oriented cars go for the 98RON fuel that has no ethanol mixed in. The only step up we have left then at some petrol stations is E85.
×
×
  • Create New...