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I got mine from Tilbrooks here in Adelaide 0882618619, Mick who used to be with sub zero is making them. Not sure on prices but they look dam impresive, mine has also got a xf 90mm throttle body.

Guest drift_me_silly

Mattr, pls post a pic when u can.....is is similar to the brain plenum?...my one and only reservation with locally custom made plenums is that they're more often than not a one-off, not a flow benched many time reconfigured item...having said that, i'd still lean towards a local than pay for an imported plenum...

Predator, less piping is great for response, don't get me wrong...but factory plenums have so much reasearch, they're unbeatable....newayz...

Hi guys, I still worry about the distribution inside a lot of the aftermarket plenums (that includes the Greddy ones). The standard RB20/RB25 inlet manifold has a lot going for it.

Heat soak is not really a performance disadvantage as the air spends so little time in the manifold and at such hi velocity it does not absorb any heat from the manifold. Pipe length is really the only disadvantage.

We use the Gibson R31 GTSR design of pipework, with the 1 X 120 degree bend rather than the 3 X 90 degree bends. Cuts down the pipe length a lot and still gives the good distribution and long runners of the standard manifold.

I have seen too many poor flow bench results for aftermarket inlet manifolds to trust them without a copy of a certified flow bench test attached.

Hope that adds to the discussion.

Sydneykid, I have the Greddy one and have found a substantial gain in the mid-range just by adding it, plus at high rpm it doesn't fall off power as quick. Can't say what the distribution to each cylinder is like though.

Originally posted by meggala

ican get these for around 600 650

plenium1.jpg

Meggala? are u serious i mean WTF is that?

people would prob want there engine bay to look factory, not a scrap metal yard. I think i could do better with a welder and some sheet bay, i mean how much R&D went into that!

The factory unit is good in its design. It could be improved by a tapered connection to the throttle body and a little more volume.

Here is where you get swings and roundabouts. shorter, straighter path to plenum Vs more even distribution into the cylinder head.

If you can have your cake and eat it thats fantastic. But I'd lean towards a better design of plenum giving you more power and torque benifits over shorter pipe work (within reason). There is substancial turbulence in the plenum and creating smoother and even airflow to each runner is as much art and luck as it is physics. Therefore substancial research would be required to get the plenum working 'plumb'.

If there is clear evidence of development behind the plenum then its worth a shot, otherwise you are spending good money on a placebo.

I've heard some very good things about the trust unit. The only problem people have is putting too big a throttle body on it for the flow of the turbo.

Originally posted by judd

Meggala? are u serious i mean WTF is that?

people would prob want there engine bay to look factory, not a scrap metal yard. I think i could do better with a welder and some sheet metal

:confused:

Why the attack? No need to be so narky about it is there?

Yes it looks crude. I still don't see a need to attack him over it. :headspin:

I like that plenum.....

tell everyone you made it yourself if you think it looks dodgy, then they'll be impressed. And who cares what the hell anything looks like, as long as it goes fast

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