Jump to content
SAU Community

Recommended Posts

plenum looks cool ~~..I reckon if it's going to cost $600 get the Greddy ones, the Stock TB is not going to fit into the plenum unless you have them custom made....either get an adapter plate or change the TB.

If you do change the TB, the traction control will be removed. You notice that The Gtts have longer TB than normal...hence replacing the TB will require some custom pipe to be made to replace that length...

with the Greddy ones I think you'll need top feed injectors and fuel rails

but dont u HAVE a r34 GT-T????

why would u want another plenum for when u already got one of them on ur car

unless its a aftermarket front throttle body opening one that ur talking about

Yes, I want the after market one.

less piping and cooler induction.

the aftermarket plenums are forward facing , so you cut out all the cross over the engine part of the piping

but the stock plenum is good for lots of HP and flows very well , not really a worth it just to cut a foot and half of piping out

well actually for me it at less 3 foots.

the way I see it .....less volume=easier compression=less stress on the turbo..

=cooler air= better preformance.

3 foot is still nothing

your theory is correct but in practise there will be virtually no benefit

also lots of the aftermarket (cheaper) plenums are poorly designed , dont flow as well and tend to have uneven air distribution across all the cylinders casing some of them to run rich or lean

apart from the visual appearance no benefit has been covered many times in the forced induction section if you want to search

The stock plenum is better than a crap el'cheapo one.

However a well made unit is another story. The plazmaman plenums increase power over a stock plenum as a bolt on ($1,100 no crap required unlike the Greddy) not to mention the benifit from reduced piping volume, length and very restrictive bends.

The stock plenum might be good for 500hp. A good aftermarket one will get 500hp with less effort.

The cheapo units however are not worth bothering with. $1,100 for a good bolt on one is value.

i agree. the stock plenum is good for close to 500hp so unless your shooting for big numbers or have a space issue then i would put the dollars into something worth wild

are you sure? I think they'll only last to abt 350-400hp

and you can use the Greeddy r33 gtst ones to suit r34...I got them off Nengun for $1020

these units are direct bolt on as well...at least that's what I was told...haven't fit them yet

well over 350hp

350rwkw easy on the stock plenum , apart from the annoying cross over i/c piping its a a very good intake

to be honest, it hard to judge unless there someone actually done some experiment on it.

theory is all good and I do appreciate everyone opinions.

by the way had anyone read about it or had converted the standard 25det plenum or any cross over plenum to non cross over?

I, myself witness my mate did it to his Mk3 Supra but he also did few other mods as well so we couldn’t really judge if the cross over had makes any difference.

But I think I can work it out if we will pull all the paper works out and investigate. it that is if he still got all of the paper work.

there is lots and lots of evidence , pre and post dyno runs in the forced induction forum , search

its been pretty well gone over now , no flow increase for the aftermarket plenums at this power level

you can convert stock to fwd facing but you have the same problem with uneven air distribution

get the proper greddy one if you want to do it , not that expensive and they work properly . just no flow gain.

look good though

Edited by arkon

Honestly the fact that the plenum allows 350rwkw worth of air through it means very little. Air flow restrictions to an extent can be overcome by working the 'air pump' (engine) harder.

The good thing about the factory plenum is that it had long runners for better off boost performance and is pretty good at evenly distributing the air going into it at moderate power levels. It has a fairly low volume plenum chamber for suited to the airflow needs of the factory engine, helping with low end rpm response.

The bad things are that , the plenum chamber volume is a tad small for bigger power levels requiring bigger airflow and cylinder fill rates. It will be well down on power compared to a good aftermarket unit with the same equipment. At 500hp I'd say there would be a significant difference indeed. It faces in such a direction as to cause restriction and dull response when coupled to a FMIC (not an issue with the factory side mount though).

As for modification of the factory plenum, Grandenko did this to his RB25det and reported no ill effects and increased response. As to whether the cylinders fill evenly I'd say there may be an issue as the stock plenum isn't tapered to suit the front feed airflow bias to the rear cylinders.

  • 2 weeks later...

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

    • Yeah, it's getting like that, my daughter is coming over on Thursday to help me remove the bonnet so I can install the Carbuilders underbonnet stuff,  I might get her to give me a hand and remove the hardtop, maybe, because on really hot days the detachable hardtop helps the aircon keep the interior cool, the heat just punches straight through to rag top I also don't have enough hair for the "wind in the hair" experience, so there is that....LOL
    • Could be falling edge/rising edge is set wrong. Are you getting sync errors?
    • On BMWs what I do because I'm more confident that I can't instantly crush the pinch welds and do thousands of USD in chassis damage is use a set of rubber jacking pads designed to protect the chassis/plastic adapter and raise a corner of the car, place the aforementioned 2x12 inch wooden planks under a tire, drop the car, then this normally gives me enough clearance to get to the front central jack point. If you don't need it to be a ramp it only needs to be 1-1.5 feet long. On my R33 I do not trust the pinch welds to tolerate any of this so I drive up on the ramps. Before then when I had to get a new floor jack that no longer cleared the front lip I removed it to get enough clearance to put the jack under it. Once you're on the ramps once you simply never let the car down to the ground. It lives on the ramps or on jack stands.
    • Nah. You need 2x taps for anything that you cannot pass the tap all the way through. And even then, there's a point in response to the above which I will come back to. The 2x taps are 1x tapered for starting, and 1x plug tap for working to the bottom of blind holes. That block's port is effectively a blind hole from the perspective of the tap. The tapered tap/tapered thread response. You don't ever leave a female hole tapered. They are supposed to be parallel, hence the wide section of a tapered tap being parallel, the existince of plug taps, etc. The male is tapered so that it will eventually get too fat for the female thread, and yes, there is some risk if the tapped length of the female hole doesn't offer enough threads, that it will not lock up very nicely. But you can always buzz off the extra length on the male thread, and the tape is very good at adding bulk to the joint.
    • Nice....looking forward to that update
×
×
  • Create New...