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saw this on the SDU site thought you might be interested

http://forums.skylinesdownunder.co.nz/show...&threadid=45316

shame the pictures dont show how long the runners are from the plenum ...

Neat looking plenum though!

I would not waste time let alone money bolting that thing onto an RB26 . As has been said before show us an across the board gain and it'll sell . I think they're hideous looking things and a better all round result would come from std bits . If they can prove to function better I'l gladly eat my words .

Cheers A

This is the response I put up on SDU;

Pardon me for being sceptical, but I have tried a number of aftermarket plenums and most give an average power LOSS. Some are only barely as good as standard. I have not found one that actually gives a power increase.

So, do you have any dyno graphs showing before and after dyno results? No other mods, just the plenum and relevant pipework change.

PS; if you haven't done a back to back dyno test, I strongly suggest you do. Otherwise you will get nothing but grief from the sceptics who have been burnt by others.

you can buy the kits off ebay (US) for around $US200. I had one welded for a customer and they are a crap quality cast with plenty of pin holes and the bellmouths were also cast, measuring 25-30mm in length.

total costs if you were to buy one in pieces and have it welded you could saves yourself $150-$200.

not worth the hassle. there are "other" optins out there with a superior finish and proven performance for an extra $200-$300

Jap Performance's reply to SK:

Sydneykid - on a completely stock std vehicle there will not be any benefit and more than likely loose power, the reason should be pretty simple.

...is the simple answer is that they are no good? seems like an empty response that doesn't answer any questions, to me...

Jap Performance's reply to SK:

Sydneykid - on a completely stock std vehicle there will not be any benefit and more than likely loose power, the reason should be pretty simple.

...is the simple answer is that they are no good? seems like an empty response that doesn't answer any questions, to me...

I think he thought I meant that the car was to have no mods before the plenum was fitted ie; standard. :(:O

What I meant was no mods after the plenum was fitted, ie; just a simple before and after comparison of what the plenum did for a car that alreay had mods. : :)

I would not waste time let alone money bolting that thing onto an RB26 . As has been said before show us an across the board gain and it'll sell . I think they're hideous looking things and a better all round result would come from std bits . If they can prove to function better I'l gladly eat my words .

Cheers  A

My comment was made regarding its aesthetics. I totally agree I would not consider using this plenum.

Gary, what do you think about the JUN plenum?

My 2 bobs worth on that plenum assy.

It looks all wrong. It's angle relative to the direction the airflow has to travell is too severe to me. It may have the actual correct plenum area, but just not put in a practical position. No.1 cylinder would get a different air signal than No.6 cylinder, wich means you'll have to run an ECU that trims injectors for deficient balance of the engines breathing hardware, which is a bandaid approach for a balanced setup.

And the 80 or so mm throttle body mount is in my opinion way too large for an RB20/25.

That's my thoughts on these type of plenum assemblies. And the fact that they are so much money to buy. Waste of time.

I have a modified stock plenum assembly on my race car, check that out on my RB Racing post soon.

Turbine.

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