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Hi Guys,

I'm just about to fit a GReddy/Trust plenum to my car - and will be doing back to back dyno runs before and after the swap with no other parts else being changed, maybe a bit of a teak on the tune depending on what we see. - So I'll have a good idea finally on exactly what gains to be expected. (My car not stock tho, so results will be in the context of my car)

I'm very excited about this change so I'll post the the results after I get them.

Cheers,

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Why would nissan put it on most of the skyline models if it wasent efficent and obiously they have spent alot of R&D on it.

I'm not necessarily convinced that these plenums are a good bang for buck upgrade, but I'm always amazed that people say this!?

anyone who has ever worked in an engineering environment knows that in design, there are two considerations

1.) is the design fit for purpose

2.) cost

the notion that nissan spent years pondering the best way to extract small HP improvements and maximum flow from their plenums is just ridiculous. The factory plenum is designed to be as cheap as possible to manufacture, whilst still performing the job adequately for purpose - i.e. low boost road use applications.

it's like saying that they spent a bucketload on r&d for their gts-t intercoolers - because nissan engineers and nissans are good. yet everyone knows that the factory intercoolers have got knobs.

the question for me on the plenum is - can you get it at a cheap enough price to justify the opportunity cost against other mods. i.e., if I spent that (up to) $2500 on something else, could I have acheived a better end result? I'd say no, unless you've done a lot already.

however, if you start talking about $800 instead of $2500...... :D

Why would nissan put it on most of the skyline models if it wasent efficent and obiously they have spent alot of R&D on it.

And why would TRUST/GReddy sell these plenums if they did nothing. And a Good 99% of Jap-tuned beasts have aftermarket plenums.

That's the biggest load of rubbish I've ever heard.

well basically what i'm doin is replacing the plenum on a stock as a rock RB25DET - my reasons are - because i'm putting it in a Silvia and i want the plenum to be clear of the bonnet and for cooler piping reasons - also because i "thought" it gave it a bit more power

so - does the Greddy plenum give the stock RB25DET some more power - if so .. is it worth it because i can get the greddy plenum (surge tank they call it as well?) for about $1100 (about that) delivered to my door.

cheers

BRAD

does the Greddy plenum give the stock RB25DET some more power?

evidently, yes.

if so .. is it worth it because i can get the greddy plenum (surge tank they call it as well?) for about $1100 (about that) delivered to my door.

that, my friend, is up to you to decide.

do you want it because of the performance increase or because of the ease of piping/fitting or both?

bear in mind that you will probably save some money on piping a FMIC if you have a front facing plenum.

thats what i'm still trying to decide - whether its better to pay extra for cooler piping (being stock p[lenum) and puit some of the money towards other shit. but keep thinking as its going into a s13 and the stock plenum does cause some trobbles with the bonnet clearing - as the greddy plenum will sovle it :D i dno hey i still need some "Steering" in the right direction

well basically what i'm doin is replacing the plenum on a stock as a rock RB25DET - my reasons are - because i'm putting it in a Silvia and i want the plenum to be clear of the bonnet and for cooler piping reasons - also because i "thought" it gave it a bit more power

so - does the Greddy plenum give the stock RB25DET some more power - if so .. is it worth it because i can get the greddy plenum (surge tank they call it as well?) for about $1100 (about that) delivered to my door.

cheers

BRAD

Think you might find it's a bit more than that , especially if Customs wants their bit.

Cheers

Ken

o hey Ken :D  quote from Greenline - "Hope that you had a good Christmas and New Year.  

Thanks for your enquiry. Pricing information as requested:  

TRUST Surge Tank (Intake Plenum) R33 GTSt: 78,540 yen  

Shipping: 14,100 yen  

TOTAL: 92,640 yen AU$1158 "

:)

Yep agreed and I actually have one coming and is in Melbourne clearing depot.

They are looking VERY hard at stuff from Japan atm , and I expect to pay customs and duty which will add approx $500 to the cost.

If your lucky you will get it for the price quoted but don't rely on that being the final price.

Cheers

Ken

$500 ??? How does that work ?

Damn - I hope I don't get slugged that much  ! ! ! :(

On the amount already paid for shipping, you can get slugged for import duty (from 11-15% if I recall correctly depending on the type of goods). On top of that you'll then be slugged GST on the original amount with shipping plus the import duty (tax on a tax). Might not be $500, but then I'm not sure how much Ken's got coming in.

I got some HKS dump pipes for my 'R from Greenline, paid just over $700 I think including shipping, unfortunately the shipping bill said the value was $0.00 which of course on a brand new HKS box made them suspicious. So being the honest person I am, I took down the correct invoice and got charged about $190 extra in import duty and GST.

In either case, it bites big time.

Price of plenum $1158

Duty @ 15% $174

Total $1332

GST @ 10% $134

Total $1466

$1466

- $1158

Extra $308

Sorry , forgot that the price of $1158 included shipping.

The price that any company o/seas quotes does not usually include these charges.

If you are lucky , it may come to your doorstep without paying the extra charges but do not rely on that.

cheers

Ken

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