SR20DEN

iTrader: (7)

Nope.


And I am still not convinvced that the 2k1 manifold doesn't have two runners. I'll find the correct answer at lunch time.

IceY2K1

iTrader: (3)

Me either, but unless you disect one like Thaniel says, I don't think you can tell.

SR20DEN

iTrader: (7)

I know I have seen pictures of this thing and I have seen 6 butterflies. Sooner or later I will find that info again.

IceY2K1

iTrader: (3)

I can say this...it's ONLY the main plenum-->box part I'm in question about.

The power valve side DEFINITELY has two runners merging, long over the top and short underneath. The short underneath runners(coming from the box) are covered by the power valve and if you turn the VIAS rod, it opens to uncover the shorter runners. However, the long runner is still open.

If the main plenum dumps into a second plenum box that at least the short runners ALL share, it's still a dual runner intake IMO. It just has a dual tank design vs. single like the 2K2s.

How does the MEVI work?

IceY2K1

iTrader: (3)

Yes...IMO.

I think that would be the BEST way to go. However, getting all the vacuum lines/sensor connections/etc. converted would probably be a major task until a few people document what goes where.

I'd keep the old ECU of course. Hopefully, all the sensors are compatible.

Thaniel

The MEVI has butterfly valves. The DE-K has one nylon bar with flats molded into it. It is one piece (nice thing is no chance for the screws to come loose and fall in the engine as there aren't any on bar). Each cylinder has only one opening into the chamber. The bar or Powervalve rotates to let air flow into the chamber. From there it has no where to go except out through a different cylinders runner. There is no second opening. one for each cylinder that's it.

Once ICE removes the power valve and looks in he can report back. I'll also try and get some pics looking in from the cut side, although I don't have a place to post them.

It still helps performance (dynos are proof) but It is not a 2 runner system as I had previously thought.

If I understand how the MEVI works it is the exact same. THE plate that bolts on to the top is the top of the chamber. when the butterflys open it allows the runners to be connected (throught the chamber). closed they breath through their own runner.

I think performance differences between MEVI and DE-K intakes would be subtle due to the slightly different contours of the runners and valves (all else being equal which it rarely is).

I just find the whole thing interesting. I like knowing how stuff works.

SteVTEC

SAE TECHNICAL
PAPER SERIES 2000-01-0668
Second Generation of High-Response V6
Engine Series (3.0 and 3.5 Liters)
Toshiya Arai, Junichi Yajima,
Keiichi Murata and Masahiro Hibino
Nissan Motor Co., Ltd.

Cross Sectional view of the VQ35DE



You can clearly see the multiple path setup in the runners, and the red circle is where the valve is. When it's closed, air follows the long path with the 180 degree turn for low-end torque. At higher revs above 3800rpm the valve opens and air follows the shorter direct path from the upper into the lower intake manifold.

Unfortunately the document doesn't have a diagram of the DE-K. Also, I'm not sure "which" VQ35DE this is. If the 02-03 Maxima upper IM does NOT look like this then that would go a long way towards unravelling the whole VQ35DE "Series II, Series II.5, Series III" mystery.

DAVE Sz

iTrader: (2)

No one is disagreeing that there is one opening per cylinder. What ICE was saying that there are 2 runners inside the plenum that in the end use the same opening to push air into the cylinders. Look at the de-k manifold, it looks like it has a hump compared to the DE. The way it looks you can conclude that the longer runners are the ones the you see from the top and the short ones are under those. They aren't bent like the long ones making them starighter and shorter. When you hit 5k rpm, the butterflies open and the air takes the shorter path which is the lower runners. Where the MEVI uses the extra space to change the sound of the incoming air to make power, the DE-K uses a different path for the air to get power.

SteVTEC

Rather, the MEVI (at least how I understand it from what I know), changes the resonant frequency of the upper IM itself such that the manifold works optimally at higher RPMs. From another technical document I have, it "looks like" a side branch resonator setup which would accomplish just that. Both setups (multiple path runners, or multiple resonance single path) are both just different ways of accomplishing the same thing.

Tatanko

iTrader: (34)

If it's possible to do all of this, I personally would (when I actually get the car) be willing to try this. However, I wouldn't want to do it if I couldn't use an older ECU (95 or 96 so it's reprogrammable). But, the only way to find out is to try I guess. Another thing that concerns me is the ability to do stuff like the stroker engine or a VQ35 shortblock swap like people have done/are doing with the VQ30DE. It seems like it should be able to be done the same way, but...?

And if the 02-03 Maxima doesn't have it, there's another way those guys could go about getting power like we're doing with the DE-K manifold

BSwithTF

iTrader: (8)

It seems the DE-k manifold is quite similar to the MEVI. From what I can see on mine it looks like the box on the lower may shorten the path somewhat but it still uses the same runners. Almost like it opens up the manifold so that it can hold a greater volume of air and get it to the cylinders quicker. I haven't pulled the valve out but I did look up into the manifold and move the valve back and forth.

I've been looking at this IACV problem for the last couple of days. I had mentioned in a different thread about maybe running without the EGR. If this will work properly without the EGR, I have made a bracket that will mount the IACV in the hole presently used by the EGR. Now, I realize this is not for everyone as most have to run their EGR but it simplifies the install somwhat as now there is a simple plate that bolts to the bottom of the manifold. Keeps the throttle body from being so far away and the IACV is in relatively the same place. Only problem I can see is whether or not there is room for the IACV to hang down. I think there will be but haven't had time to fit it up to the motor yet.

Any thoughts on this? It really hinges on two things: 1) How will the motor run without an operating EGR? 2) Is there sufficient clearance for the IACV to hang below?

IceY2K1

iTrader: (3)

Yes, into the primary chamber after the throttle-body, however there is a secondary chamber that feeds the short runners that the longer runner NEVER sees.

You mean cylinder, right? The power valve(nylon bar) prevents airflow EXITing the secondary chamber into the cylinder from the shorter runner.

Or are you saying that the power valve opens/closes airflow from the primary chamber to the secondary chamber?

DEK manifold? I don't get that. Please explain.

Agree...right after the power valve(nylon rod), the long and short MERGE into *ONE* runner before entering the lower manifold. That doesn't mean it's not a DUAL runner before that though.

My impression of the manifold showed the longer runner(over the top) connects to the primary chamber behind the throttle body. However, I *THINK* that runner was split into two paths, one continues as the long runner the other dumped into a secondary chamber(box underneath) that you say is common to all short runners.

If the power valve is closed, all air flow will travel through the long runner split bypassing the secondary chamber and merging AFTER the power valve with the SHORT runner.

If the power valve is open, all air flow will travel through the long runner split into the secondary chamber, past the power valve, and merging AFTER the power valve with the LONG runner.

Summary of 2-Paths:
-----------------------
Power valve CLOSED(long path):
TB-->Primary Plenum-->Long runner-->Merge-->LIM
Power valve OPEN(short path):
TB-->Primary Plenum-->Long runner-->Secondary Plenum-->Power valve-->Merge-->LIM

Just throw them in a www.cardomain.com page.

I think we're getting there, but there is one ENTRANCE(a common starting point) and one EXIT(common finishing point), but it splits in the middle to form a second shorter path, isn't that a 2-runner system? I think so.

Ignoring the composite plastic vs. metal advantages, you don't consider the DEK to be a more "stream-lined" path for air to travel then the MEVI?

d_warner

OK. I've read this thread and nobody has asked, so I will. The piece that is custom fabricated mates the idle air control valve and other sensors to the 5th gen manifold. and also serves as an adapter plate for the throttle body. Would it be possible to just use the idle air control valve and throttle body from the DE-K motor in the 4th gen? You're already messing with wiring on the injectors, whats 3 more sensors and valves? Or was there another reason for fabricating this piece?

David

IceY2K1

iTrader: (3)

Definitely not a VQ35 Maxima IMO looking at SR's pics.

IceY2K1

iTrader: (3)

I agree...a DEK throttle-body/IACV combo would be better, but doubt it would work withOUT the 5th gen ECU.

The reason I say that is that the IACV is a stepper motor that is controlled by the ECU.

Maybe the 4th gen uses a similar IACV?

BSwithTF

iTrader: (8)

No go on the bracket. I did some test fitting to see if it'd squeeze back there and it won't. It's squeezed up to tight to the rear valve cover/head. Back to the drawing board.

IceY2K1

iTrader: (3)

I mentioned it before, but if someone doesn't come up with a better way for the IACV, I can PROBABLY duplicate/mass produce those IACV adapter plates.

I'd just need one or at least some CAD type drawing to give a CNC machinest friend and see what he would charge for something like that. Wouldn't hurt to ask him.

BlueC

iTrader: (5)

Seems like it'd be cheaper to go find a 2k/2k1 engine at a junkyard. I see them on car-part.com for as low as $400. Either swap it in (if it works), or use the manifold, injectors, etc. Then you could part the rest of the stuff, or keep it for another project.

IceY2K1

iTrader: (3)

Exactly....

A complete DEK would be best, but you could probably part out the short-block/heads for half, if not more.

If anyone is thinking about try it, I may be interested in the heads w/all guts.

BSwithTF

iTrader: (8)

That may be what we have to do. The more I look at it, that's about the only way to do it. Now if we can talk krismax into making another one. This piece is my only hurdle at this point.

As far as motors go, I watched Ebay forever and found mine. '00 DE-k w/ auto tranny: $465. The tranny had a small chunk out of the case so the guy just threw it in to get rid of it. Should be fixable but even if it's not, I got a '00 DE-k with 16k miles on it for dirt cheap. They're out there, just gotta look all over and be patient.

My swap will be a little different though. I've removed the A/C and I'll probably do away with the P/S to ease the swap. Maybe later doing the electric P/S like krismax did. I'll be sure to note any difference's and problems that I encounter going from a DE to a DE-k so I can pass them on.

Tatanko

iTrader: (34)

Thank you

IceY2K1

iTrader: (3)

Dixit picked up his DEK w/tranny for SUPER cheap. Guys in junkyards on www.car-part.com seem to want BIG money, but little yards don't.

Just got to look hard enough, I guess.

SR20DEN

iTrader: (7)

Notice the shape and directions of the exhaust manifolds. This is the Pathfinder engine.

Unless this is an overseas version. No other US spec RWD VQ35 uses a VI setup (other than Pathfinder/QX4).

Also take a look at the link on this page.

Variable Intake system

SR20DEN

iTrader: (7)

The 2k2 manifold is VI based just not the same as the other ones. And I already made mine peak out the way the DE-K manifold does.

SR20DEN

iTrader: (7)

That IS a two runner system. The longer path goes over the top and the shorter 'bypass' path opens up underneith.

d_warner

Yeah man, but I think what everyone is saying is that the US made VQ35's don't use the Dual runners like the overseas cars. That photo is a PathFinder 3.5. I could be wrong though. Maybe I just need to re-read.

SR20DEN

iTrader: (7)

Hmmmmm..... this Pathfinder setup looks veeerrryyy interesting.

BSwithTF

iTrader: (8)

Now THAT is a dual runner set-up. Who's gonna try this one?

krismax

iTrader: (15)

You guys need to understand that if you use the 2000-2001 engine all forth gen sensors need to be switched over or you can use 5 th gen ecu .No sensors can be used on 5th gen . Or you can wire a standalone ecu in.
I find it funny how I figured the easiest way to do this now people are looking for a more complex way of doing this. My adapter is just a square with holes in it with the 4th gen IACV face welded on .Solves alll the problems.

Quicksilver

iTrader: (1)

It does look doable, but the RWD thing might be hard to overcome. Anyway, Adam (maximaman777) and I are doing the G35 intake thing this Saturday. I'll make sure to take plenty of pictures and document everything...

Tatanko

iTrader: (34)

Is a 4th gen ECU do-able with the entire DE-K? That way you wouldn't have to switch over to any of the 5th gen sensors.

SR20DEN

iTrader: (7)

I still don't think it's doable without excessive amounts of custom fabbing. But good luck.

Next week I plan to start on stage II of my secret sauce project. This one might fare better for the automatics.

krismax

iTrader: (15)

You cant use 5th gen sensors without 5th gen ecu. Yes you can use the entire engine but it will take alot of work and time . And you still have to do the same thing I did with the DE-k manifold.

Tatanko

iTrader: (34)

So then to use the entire DE-K engine you'd HAVE to have a 5th gen ECU? When I said 4th gen ECU I should have been more specific, I meant specifically from a 99.5.

SR20DEN

iTrader: (7)

Using the A33 ECU would be ideal but I think the project can be done without it. You would need a rpm switch to control the VI though.

BlueC

iTrader: (5)

Well, what if you only use the DE-K cyl heads and the intake manifold (and other accessories needed).... then will it still work with my ECU? (Im a 99.5 btw)

Tatanko

iTrader: (34)

Well the RPM switch is no big deal, it's just a matter of using the A32 ECU to keep everything you'd otherwise lose with an A33 ECU. Btw, does it matter what A32 ECU it is? Since there's like 4 different ones...

BSwithTF

iTrader: (8)

One thing I've noticed already is there is an additional coolant hose on the DE-k. It comes up from between the heads, in the valley where the knock sensor is located. Looks like it makes it impossible to get to the KS with the traditional method of extension with swivel. I think I may have to locate that pipe that connects the heads cause my '96 pipe isn't gonna work.

All the sensors/injectors/etc. on the DE-k use a different style connector. I noticed this while taking the wiring harness off. I like trhe new style much better than the DE style. Hell of a lot easier to disconnect.

IceY2K1

iTrader: (3)

Three words...YOU ARE CORRECT~!!!!!

First, I'd like to say WOW, what a fascinating, yet simple design. Explaining it withOUT pics will be tough, but I'll try.

There are two plenums, I'll call primary(behind throttle-body) and secondary(box underneath). The primary feeds the six LONG runners you see on top. These runners terminate into the lower intake manifold six ports. However, before they do, there is another path exiting the secondary plenum that merges, which is blocked by the power valve. The power valve is a long rectangular shaped rod which rotates somewhat like a vacuum cleaner brush, ie every section wall has a round O-ring, except it only turns 90-degrees. If the power valve is closed, it closes off the secondary plenum from any air entering or leaving, however inside it's ONE big open box, ie all six runners are connected.

When the power valve is closed, the primary plenum feeds the long runners and they dump into the lower intake manifold, nothing special.

Now, for the fascinating part, which I *THINK* I have figured out, but I could be wrong. When the power valve is open, the current cylinder performing an intake stroke draws from the closest source, ie secondary plenum, which the OTHER runners are now feeding. So, instead of the intake stroke drawing through a SINGLE long runner/primary plenum like under 5000rpm, it's now drawing through an effectively much LARGER volume contained in the secondary plenum, other FIVE long runners, and the primary plenum.

I don't have proof or anything, yet, however I'd be willing to bet this is a form of dynamic supercharging called "tuned-intake tube charging" or another version. Per my SAE handbook, tuned-intake tube charging is defined as:

Anyways, I'm GOING to take pics, I just have to find a digital camera and figure out a way to get clean shots.

DAVE Sz

iTrader: (2)

Why don't we all just ask VSAMAYLOV or whatever he's called what went into swapping the DE-K into the 4th gen? He said there was barely any modifications needed, moving the thermostat and stuff like that.