UAS RB20/25 Intake Plenum.

[Boosted Zed]

Sydneykid the intercooler on car tested was not ours but Plasmaman with the better core. I know the car as sold it years ago to Barry Jacobs from Serious Biz and has a stock turbo.

BBQ No we don't play with dyno to bodge figures. We did not have before figures with this car and it took many months to make this kit and jig for it to be able to do others. We only found out about it after we tested on our dyno. We had no gain to make figures positive and even if did we would not do this.

No they are not polished inside but as you can see the base plate is smooth and has trumpets machined into the thick base plate. Then the top piece is also a work of art as it is pressed and made from sheet alloy so also smooth and tapers towards the back to help with more even flow to each runner. I have seen some backyard jobs which flex and a bit rough and no comparison. With out doing a bulk run they would not be viable as too much set up and machining, for one or two this quality would cost a small fortune.

BBQ No it was normal premium unleaded pump gas, no funny business and we were surprised it made this power also. I was so impressed I chased Oyay ( Plasmaman ) down and said we must have these as by far the best we have seen and the quality etc and only got better when I saw the base plates this week. The man is a genius and true craftsman. We are hooking up big time on lots of items stay tuned.

No pinging and no adjusting timing, no prob with inlet temp sensor. Ben and Adam who run our dyno are not marketing mechanics and will not or would not fudge anything, they are more like technicians and their personality is the opposite end of bullshit. They tell it as it is.

Rough surface is not good for flow at all that is why extrude hone works so much better for flow as smoothes out rough casting.

Also keep in mind that the boost was only 12psi less than most making lots less power with more boost. Engine will run cooler and longer as less stress and less heat probs at the track. No you would not get plenum and intercooler before exhaust but just think if what I am saying and reporting is true then it blows some theories and money spent on lots of other things out the window a bit. If this car tested did have a full exhaust and Power FC or Microtech etc it would make more power again but maybe not a lot as turbo is over it's efficiency. It would do it easier that is for sure.

Hey BMan good idea and I think I spoke to new owner re this option. It would be a real test then. Bman do you have the figures or are they on SAU somewhere from last year when we had results from RB25 stock plenum flow bench tests or I did them up?

Any candidates out there with a Greddy plenum I will do a deal as I often do that we swap and if does not make at least a few rwkw more power then it is FREE, same deal with stock intake. I will bet my house and throw in my zed that the result will be positive and probably make a decent gain, and more with changing to intercooler also depending on what you have already.

By the way we did lots of tests and changes to engine pipes on FTO's and nearly gave up after we hit $2000 in parts and labour r & r and changing and testing different lengths and pipe size and check with specialist books on extractors and exhaust design etc. Finally sorted and then released after proving around 3 to 5 kw at wheels gain. Not bad for normally aspirated motor. My cash flow was relieved when we sold about twenty, mainly in a group buy. If it did not work we would not have released them.

[siksII]

http://www.skylinesaustralia.com/forums/at...achmentid=25735

 This car has:

 209.5kW 96 Series 2

  Engine management - Stock ECU

  Boost ran - 12psi

  Turbo - HKS 2540

  Fuel used - BP Ultimate

  Stock all other internals.

  Blitz DSBC 1st gen

  Hybrid Front Mount

  3" Exhuast from turbo back

  Pod Filter

  Stock BOV

Hey abo,

that car has a 2540!! anyway, besides that, i just want to say that i believe the dyno at unigroup reads higher than others, as an example, i ran my old gts-t on the dyno there it only had a catback(with a 2.5" muffler in the middle to remove defect) and a panel filter, stock everything else, and it pulled 165rwkw shootout mode.

on the same day (group dyno day) i saw ~6 na z32s(with small mods) pull ~130-135rwkw, which i thought was too high, as gtst-s make that kind of power when not much far from stock. i was thinking crap my car is only as powerful as an n/a z32, until i ran it

so the 209rwkw with stock computer may be a bit misleading when comparing with other dynos.

[R31Nismoid]

He he - I knew this would happen.

 

John - get my old car. Do a dyno run before (with the Greddy plenum). Then take the Greddy plenum off - Put the UAS one on , with the polishes bottom runners and then put it on the dyno again - then post the dyno graphs of before and after.

is it asking too much to use the stock one?

[Wazz]

if i was down south in that area.. i'd definately hit you up on that dyno it with stock plenum n fmic than dyno it with uas plenum.. as im really keen to see the difference on a rb20 with stock everything cept rb25 turbo... there nice looking plenums.. but.. why make just the top half? and also for 1500.. that seems a bit steep just for a top half maybe if it was a full one piece plenum yer but meh either way.. i want to see the difference on a rb20 compared to stock plenum

[Boosted Zed]

Not expensive for what they are and the tooling and machine work and smarts gone in. I don't think there is anything wrong with lower plenum although as mentioned can be improved with extrude hone. If made the lower runners, that is if there would be a gain they would be much more expensive and already saying too much. Everything is too much for Silvia's - 180SX and R32 GTS-T's as the cars are not worth much. We have not done final costings on them and may work out cheaper. Pretty good bang for buck for Skyline though. Waz up North Qld with heat you could really benefit with one.

RB20 more efficient motor than RB25 as we find generally same condition and features RB20 and 25 make similar h power or RB20 a little behind but not equivalent to .5 litre. I would expect the improvements same though.

Also for those with FMCI already and just want plenum which will be most I suspect we will be able to provide piping to meet up with throttle body and your intercooler pipe, as all are pretty similar and go through inner skirt just below washer bottle on drivers side where 3 inch hole is cut in inner skirt.

[Roy]

LOL...want to use a 235-260rwkw RB20 as a test car:)

[Ginkgo Biloba]

plenums like this do make alot of difference. me and my mate tested the difference between our cars' date=' both stock rb25's, mine had custom plenum, same size turbo. mine would kick in at 2200 and hit 1 bar by 3500 and his would kick in at around 3500 and hit 1 bar by 4500 rpm. although his was running stock computer with a safc and i was running a microtech LT-16s, im sure that tuning didnt make that much of a difference.

QUOTE']

way to kill any credibility you might have dude! On one hand you have the forum's information doctor, Sydneykid, who carries out fully controlled tests using strict protocols backed up by the laws of physics and mathematical equations, and then there's "you and your mate" with two different types of engine management running "seat of pants tests" and then stating that these plenums make a lot of difference! How can you even call that a test!?

"i'm sure that tuning didnt make that much difference" who are you kidding?!?! do you know anything?!

sorry bro but i'm sick of reading bullsh!t statements from people in posts like that.

It seems Boosted Zed has opened a can of worms, as far as promoting the product it would have been better to just post all your info on your site rather than here where it can be scrutinised.

yes the power it made is extremely high for a stock ECU, stock turbo rb25, and ive seen it once before, ~200rwkw with only a FMIC exh, pod etc, but with no plenum. The AFR's on this other example were perfect, with no typical timing retard, it can only be that the stock ECU had been played with in Japan.

99.9% of the time its impossible to reach 200rwkw with a stock ECU and only the mods listed by UAS. That's why to be able to rave about this new plenum, BEFORE graph must be shown using the tock plenum. Id throw in my house and car that if you swapped the UAS plenum for a stocky, powers not gonna drop down to the typical 185rwkw mark. My bet is that the ECU whilst it is factory, it has been fiddled with elsewhere.

im not saying the plenum will not yield more power, but whos gonna pay 1500bucks for a few more kw top end?? Its the same people who believe that the setup will get rid of all their lag and give them significantly cooler intake temps.

i realise this post will rock some ships but too many people state bullsh!t on here. People like SK who spend time testing and then post results have to compete with stuff from the "me and my mate" people.

[Col-GTSX]

Interesting read guys....

Just to point out. My new S2 has a stock ecu and it turned 218rwkw.....

(Well its a stock as i know, may have been played with in japan)

Odviouslly i have a list of mods as long as my arm. Its just i was putting off the ECU mods as im not sure what i will do there yet (PFC/Wolf/Microtech)....?

I drive the car round town at 10psi and 2 deg neg exhaust which = 182rwkw

Just thought id point that one out anyway.... Cheers

[T0nyGTSt]

way to kill any credibility you might have dude!  On one hand you have the forum's information doctor, Sydneykid, who carries out fully controlled tests using strict protocols backed up by the laws of physics and mathematical equations, and then there's "you and your mate" with two different types of engine management running "seat of pants tests" and then stating that these plenums make a lot of difference!  How can you even call that a test!?

"i'm sure that tuning didnt make that much difference" who are you kidding?!?! do you know anything?!

sorry bro but i'm sick of reading bullsh!t statements from people in posts like that.

That's really harsh. I don't agree with that either. I have a PowerFC and with the right tune, it really changes the car... really really changes the power delivery so that response is much improved. The tune on my car is so good (IMO) that I've stopped a lot of mods now because it's given me the torque hit in the midrange that was missing with other tunes.

I feel for John as he truly believes this is a valid mod. I got the feeling that there's some art to the science that isn't coming up on pure bench flow tests.

I'm getting the feeling that front facing plenums are an advantage? Why are they used on the RB26 and on the 1JZ/2JZ series.

If 'cross flow' plenums are so good why aren't they on all cars?

This argument has been a popular point of interest on SAU... almost to the point that other forums have been pointing us here as some sort of definitive argument about the matter.

I think that John's plenum should show some gains over the Greddy plenum as it's clear the Greddy has some problems.

You have to ask yourself if that $1,500 is as valid as an ECU or cams. I'd go cams and ECU personally.

I'd also note that the New Zealanders have seemed to have trumped us on these items.

Besides RIPS, there's a place that makes carbon fibre plenums that sit on the original runners.

T.

[Sydneykid]

Interesting read guys....

Just to point out. My new S2 has a stock ecu and it turned 218rwkw.....

(Well its a stock as i know, may have been played with in japan)

Odviouslly i have a list of mods as long as my arm. Its just i was putting off the ECU mods as im not sure what i will do there yet (PFC/Wolf/Microtech)....?

I drive the car round town at 10psi and 2 deg neg exhaust which = 182rwkw

Just thought id point that one out anyway.... Cheers

Hi Col-GTX, since you have obviously had it on the dyno, what were the A/F ratios like? If it is leaner than 10 to 1 at 5,500 rpm then it has a modified ECU or a piggy back.

Ir only takes about 5 minutes to check the ECU, just remove the LHS kick panel and take a look. Most Tuning Shop modified ECU's have it marked on the outside case, they like to show off their brand. If not, have a look at the case retaining screws, they should have marking paint on them. If they don't or its cracked, the cover has been removed which usually means modified ECU.

Another good test is the speed limiter, jack the rear up, run it up in 5th and see if it goes over180 kph. Modified ECU's seem to always have the speed limiter removed.

You never know, you might be lucky and it has a Power FC in it already.

[Sydneykid]

I'm getting the feeling that front facing plenums are an advantage? Why are they used on the RB26 and on the 1JZ/2JZ series.T.

Hi Tony, I agree with pretty much everything you have said, this one needs a little comment though. We should not compare the RB26 inlet with an RB20/25 inlet. The RB26 has multiple throttle butterflies, one for each cylinder, all exactly the same distance from the inlet valve. This is NOT the same as having one single throttle body stuck on the front of a plenum, close to one cylinder and a long way from others.

Nissan put multiple throttle butterflies on the RB26 at great expense, in both engineering and in the parts themselves. They did it for a reason, they have stated it a number of times, that was throttle response. If they could have "gotten away" with one throttle body at the front of the plenum, they would have saved millions over the life of the RB26.

As for Toyota, the big disadvantage of the central throttle body (like on an RB20/25) is height, it makes the bonnet some 100 mm higher than it needs to be. On the previous generation engines to the 1/2JZ, Toyota had central feed plenums, but they wanted a lower bonnet line so they went for the front feed. Noting that a 2JZ is already a very tall engine, even without a central inlet feed.

Take a look at a well developed, high power, drag application, inlet plenum (Veilside, Jun etc) and note how big they are. The rule is minimum twice the volume of the engine, the bigger the better. Why? Because the more volume the plenum places between the single throttle body and the inlet valves, the more it evens out the airflow to each cylinder. The resulting dulled throttle response is not an issue on a drag car.

My 20 cents worth:cheers:

[Roy]

I'm getting the feeling that front facing plenums are an advantage? Why are they used on the RB26 and on the 1JZ/2JZ series.

 

If 'cross flow' plenums are so good why aren't they on all cars?

It wont prove a point, but if you look around there are plenty that do. Thebest example that is a straight 6 that i can think of is an M3. A monster of an NA 6 cylinder.

And to copnfise matters even further i seem to recall it uses a multi throttle setup.

[GTRgeoff]

As SK indicates, multiples are always an advantage for response and throttle control, hence the advantages of side draft webbers (and their copies like Solex) over singles in the carby days. Still today, nothing sounds better to me for induction than a NA multi throttle car. But if big numbers are your joy then a big front facing plenum with all the effort John is putting in is worth considering.

This is one of those horses for courses issues. The only true answer is "it depends" relating to your application. While I appreciate the discussion, some of it is a little rhetorical, with not enough foundation on the litmus test of "will it suit my requirements?".

Ginko, I feel you were a bit harsh in your statements, especially from one who has contributed so little to the forum with a whole 27 posts since Apr 03. Way to go on the cred dude. Some of us have at our disposal resources that allow some more scientifically based engineering judgements, while others do what they can with just the seat of the pants, and best of luck to them, at least they have a go. John is putting a serious amount of capital into developing a home grown product and deserves our support, but he also allows us to take some shots at his methodology and that takes some courage. Remember his zed is a piece of machinery to be reckoned with so respect his intent here. By posting on here he is also gaining the benefit of many opinions, after he sorts through the drama. If you think it's crap then just go back to lurking in the fringes, or offer something truly valid. John may just take you up on the offer of your house and car. If indeed it is an untouched ECU then that is an indication of the worth of this plenum in the appropriate application. Aerodynamics superimposed over the theory of impulse mechanisms is more art than science, and trial and error are just as valid as the equations. Certainly the turbo, AFM and injectors can deliver the power, but by optimising the delivery system for the air it can set up an environment of flow acceleration that outweighs it's theoretical value.

Ultimately most people won't buy from a considered position of engineering and testing but "does it look cool" and "I was in my mates car and it went fully SIK". This appears to have the potential to offer both.

Keep up the good work John, and please, continue the debate. In due course I'm certain John will produce the appropriate dyno charts, but it's up to him to release data that is really his intellectual property and possibly could limit his market advantage.

[Sydneykid]

if big numbers are your joy then a big front facing plenum with all the effort John is putting in is worth considering.

Hi Geof, that hits the nail right on the head, what are "BIG NUMBERS"?

I few years ago I used to think that 500 bhp was a big number, but we get that out of a standard (PFC & exhaust upgrade only) R34GTR now. I have seen a ZENI TANI built R34GTT (with the standard inlet system) make 475 rwhp. It had plenty of response to go with that power. Up till then I had a rule of thumb that said, change the inlet plenum when you change the pistons. But that car and another R33GTST with 425 rwhp certainly challenged that perception.

I have heard for years that you need a big plenum and big single throttle body to do a 9 in a GTR. But I have seen Theo's car do lots of 9's and it has multiple throttle bodies. I also heard that to do 9's you have to get rid of the AFM's, but Apexi VMax ran an 8 with AFM's.

Well, where does that leave me? Seems my original rule of thumb is still the best I can come up with, ie; don't change the inlet sytem unles you are changing the pistons. Because the inlet system is most certainly not going to limit the power or the response up to that point, and in light of quite a few cars now, maybe well past that point.

So the question for me remains unanswered , what are BIG NUMBERS?

[Ginkgo Biloba]

skylinegeoff its true Johns courage and effort is admirable. As for credibility, none is better than bad. You know how much time can be taken up be responding back and forth to threads on forums, hence why i rarely post. I would rather "lurk in the fringes" than waste time arguing stupid points with keyboard warriors.

you may not like what i posted and ill be the first to admit it was harsh having a go at so-and-so and his mate, but as far as offering something valid, the rest of my post is valid. The "freak" stock ECU issue has come up before and unless the UAS test car has secret mods, it has a freak ECU. Stating that the car made more power than any other rb25 skyline out of hundreds means nothing if the ECU is not typical. Simple as that. Dont get me worng, im not bagging UAS or their product, what i am saying is that the general impression from the after test is that any 33 owner can throw on the plenum package and with their stock turbo and stock ECU make 200+rwkw which is just not going to happen.

SOMEONE TELL ME IM WRONG, how many stock ECU and stock turbo cars make 200+rwkw? Sure there are a few, literally a few. And do you think these few were secretly released by nissan amongst the masses of R33's produced? No, they have been reprogrammed.

[Boosted Zed]

I had a quick read as flat out getting the slot car ready for Wakefield this Sundays Datsun Nissan Nationals race day.

Ginko Biloba no not all R33 GTS-T's with RB25 and stock turbo and ECU will make over 200rwkw and possibly most won't. This cars engine may be in much better condition than most etc etc. Still has a lot of hp for what is has and way more than it should and way more than we thought. With Ginseng as well even more power.

[cameron]

Test these intlet plenum's on more R33's to see what results you can achieve, but do a before and after test for both dyno and road!

[KamikazeR33]

it also comes down to the driver if u drive like a granny off boost all the time or if u have it to the floor all the time, multiple throttle bodies are always gonna be the best setup, but not every application has that and im sure not everyone can afford to make that system

its kinda like buying a powerfc, microtech or wolf over a motec... all comes down to money

[GTRgeoff]

What are BIG numbers SK, again it depends, but point taken. I spoke to a Qld racer yesterday who thought 400awkw was too big for the track, but that doesn't address the issue of forward facing plenums. I simply see them as another optimisation tool to be used in the appropriate role....higher rpm/high power delivery, eg. drag or dyno queen in this case.

Certainly though if a plenum like this can be used at the $1500 price range that gives a greater percentage increase for any given system configuration over the stock plenum then it may be financially more beneficial. Just taking a SWAG (scientific wild ass guess), as I have never CFD modelled the 25 intake I'd suggest over that 450 rwhp figure in the appropriate application. Simply because that's a point at which pistons should have been changed (and a fine rule of thumb to use I might add) and the rods upgraded so some money is being spent on the thing now, and to overcome the inherent restrictions in the plenum/runners (angular changes, small(ish) throttle body, joins, surface roughness, turbulent wall growth to name a few). Not that chucking some extra boost at it won't ovecome these issues, but they present tuning and logevity concerns in their own right. Principally a higher peak combustion pressure to produce the same power, so essentially the MEP chart will add up to the same area. This means something has to be working at a higher stress for zero quantative power gain.

Ginko, I can understand your thinking but for a net 8% improvement it's a bit much to suggest the ECU has to be tampered with. Ever hear of someone willing to pay $10K for a Kart engine? It just happened to be one of those freaks that everything works right on so it produces more of everything. No I didn't buy it, and nor would I, but I knew who did and it won a few national championships. For some price is little object.

Also I've had a chance to closely inspect my turbo recently to determine what mods were done to make it perform like a 2530 and i can't determine one single difference, and yet it produced 220rwkw with a fantastic mid range on stock injectors (and Malpassi FPR) with PFC. The engine was fresh with a good bottom end so maybe that contributed.

I just think you should consider the system effect rather than blithely state it must be the ECU, then bet the farm on the outcome. Also the seat of the pants is the only way a racer knows how his car feels, and most of us know the difference between a bad drive and a good one but quantifying the power is at best a guess. it can be a starting point though

[Col-GTSX]

The ecu has been opened before but no tuning sticker...

I have no idea of the origin of the ecu. It just works.... LOL

The AF's were too rich to read 10:1 flat line..... Thats why i want an after market ecu. Its unsafe to run these rich ratios all the time... Just for a dyno run is fine...

I will go aftermarket as i need it to support some current mods. Its really a week away until i decide which way to go. So ill keep you posted and ill probablly ask advice to help me make my mind up. Cheers