You'd better find one in a junkyard, since it ONLY comes as ONE piece, ie manifold/power valve/VIAS box/etc. and costs ~$375 new from DAVEB.

 

Is it possible for you to send me the RunViewer files to IceY2K1@maxima.org?

I need to compare your broken VIAS dyno to one I'm hoping to get soon.

 

Why aren't you outside turning wrenches on your car? And tell us what your mod list is please.

 

I have NONE...and why?

 

Ummm... Maybe I am confused, but I would like to see the dyno of a properly working VAIS superimposed over those gains. With the system functioning correctly shouldent you have the low-end torque of the before dyno, AND the high RPM HP of the After dyno?

Afterall, this is what the whole point of the VAIS is!

 

So would we. But since his power valve is broken we can't at this point in time.

That is correct. But the theory here is that by removing the power valve you'll gain even more top end power.

 

Not to sound stupid but if this works in one gear then it works in all? It cant be intermittent?

 

it supposedly works in every gear starting at 5200 rpms.
That is, if it is functioning at all

 

is it only the upper, lower or both intake manifold?

 

I believe that's only the upper manifold. It's all one big hunk o' plastic.

 

VIAS switchover is 5000rpm.

Is that a no on the dyno files?

 

Upper.....

 

I thought the shop manual said 5200... not that it really matters all that much

 

The FSM says "above 5000rpm", but the dynos seem to back it up.





However, sometimes it seems to go above a little.

I think it should switch sooner around 4600-4700rpm.

 

Alright. So, plan of attack.

1. Verify if my VIAS rod works properly. How do I take it out with the manifold installed in the vehicle? Remove the VIAS box, then remove the 2 screws and cover on the other side and it should pull out? (I tried pulling it out when I had just the VIAS box off, but it wouldn't budge beyond a certain point)
So the goal here is to verify that the VIAS rod isn't snapped/broken. If it is, I will either remove it altogether, or have to buy a new manifold eventually. I need low-end torque, so the latter would be preferable.

If it's not broken, then...
2. Verify that the VIAS does indeed work under no load. If it does, see if it works under load, using a stopwatch as the timer.

If the VIAS works without any load, but doesn't seem to work under load, then assume there's a vacuum issue? in which case, I either go the easy route and buy a new manifold, or start toying with the vacuum setup somehow...

 

I like secrets. Care to share the secret of the VQ35 manifold?

 

Auuugh...now I see what SR/mad2kmax were talking about.

I lucked out and chose the ONLY way it can come out withOUT noticing the other side(drivers' side hole is too small). I also had the IM not installed, which means I didn't have to worry about all the crap in the way on the passenger side. You're going to have to wait for SR to explain what does/doesn't need moved.

I'd start with #2 and once you know it's internal, find a spare junkyard IM for the guts and start looking for a way to clear room on the passenger side.

 

I need the runfiles of those other two best DE-K dynoes. Anyone have them?

 

I don't...I'm sure Max_Gator has his though.

 

OK here is a chart of mad2kmax new dyno (blue, 2k0 5spd) vs. Sloppymax dyno (red. 2k1 AE auto) vs. SR20DEN dyno (green, 2k2 6 spd)

 

JESUS

I knew that your car made alot of power, but that just looks rediculas. Pardon my spelling.

From the looks of the graph, it looks like Hayden's power valve isn't working either... dunno

 

nice to see a vq35de maxima putting down 350z numbers.... finally disproves the theory that they are completely different engines.

as for me.... my VIAS is broken also... confirmed with my whopping 160 whp/188 tq dyno

 

Looking at the poor, fragile design of this thing yesterday, it became obvious that most of the VAIS's are probably broken. Most people, however, probably will never notice. Unless your a member of the org.

 

One of the most interesting threads as of late Keep up the good work guys.

 

Given a little time, this subject will get MUCH more interesting... Like SR20DEN said earlier, the plan is to have 220+ fwhp, all motor, before we get finished.

 

wow this is interesting stuff..

but ok, shouldn't this be some kind of recall? shouldn't nissan north america be made aware of their crappy VIAS design? Couldn't the metal shavings be sucked into the combustion chambers and foul up the valves and wear the internals... couldn't a piece of plastic be sucked in and completely blow a piston?

I dunno sounds pretty unsavory to me =P

It's a good thing this thread came up. Larry was about to sell his car

 

I think I can easily remove the butterfly valves from my MEVI.....wonder if it would produce results like these. The way the valves open I can see how they restrict alot of air flow. Since we now know that the DE-K manifold works in a similar way to to the MEVI, I don't see how this would not work for me as well. Any thoughts SR?

 

As I mentioned before, I have some ideas for the MEVI. But just like the DE-K, I can't try my ideas if no one brings me a car.

 

...Then what exactly is the "secret" on the VQ35???

 

That's why it's called a "secret"

 

Hmm, OK, so looking at IceY2K1's pics -- http://www.cardomain.com/memberpage/419735/12

Which part of the VIAS power valve actually "breaks"? Is it something internal to the center of the rod (I think I see a metal rod poking out on the passenger side part of the rod)?

It looks like the VIAS power valve is one big contiguous plastic piece, but with a hole in the center for the axle rod (how does the axle rod ensure the plastic body rotates with it? or is this the core problem?), and a "key" end that fits into the actuator collar.

 

Ok.... you got me ... I guess I'll have to and see. Hey Spirillis... we should try to hook up since you just the road in Hangover.

 

Does anyone have a link that explains/shows the pros and cons of SR20DEN's throttle body coolant bypass?


A world of innocence, ruled by the power of corruption
SHIFT_woosh

 

Great work guys! You went way farther than I did to figure out how that thing works!!

I have a couple of recent dynos (before headers) in raw data - just let me know where to send them. What is amazing about mad2kmax's peak numbers is that they are the same as mine - and he's an auto! Our mods are about the same except that I have the stock muffler - not clear if he does.

I have plotted a recent run on run viewer for comparison and there's some interesting stuff going on there.

Prior to the vias mod, his hp numbers are about the same as mine below about 4700 rpms. After the vias mod, they are about 10 hp or so across the board lower BUT beginning at 4800, his hp numbers are better and he hits 200 hp 3-400 rpm sooner!

As for TQ, on his, it is down across the board substantially before 5000 but after 5000 it is identical to mine almost.

What the dynos on mad2kmax (ironic name since the the original madmax2k is a fellow tampa area resident and the current [to my knowledge] 2k/2k1 NA drag king with a 14.38 {damn that .01 - although I trapped higher}) reaffirm issomething I tried but did not dyno . . . tying open the power valve to see what happens at lower rpms.

My butt dyno said big power/tq loss below and no difference up top - so I never pursued that any further. It appears that my butt dyno may have been correct (remember I left the whole assembly in there).

The downside problem with mad2kmax's numbers is the substantial tq and hp losses below 5000. That's going to make the car slower because there's no way you make up that loss with just the high rpms. Now, if we are talking about a 3rd gear roll from 80 mph - it is a monster.

The way it stands now, I'm not certain it is a favorable trade-off BUT it looks like someone is working on that!!

 

He's got a manual.

Can you send those files to IceY2K1@maxima.org PLEASE?

Also, wait until the TechnoSquare ECU with 7100rpm limiter comes out SOON. Then you'll be able to make up that torque loss.

 

That's what I think is VERY important here.

Since SR said metal on metal, I'm thinking the metal collar to L-rod piece.

If so, then maybe all you'd need to find/change is the VIAS box end withOUT having to remove the Power Valve.

 

Also send the run files to mhwilliams@pinevilledsl.net please.

And yeah, mad2kmax has a 5 speed. And, he just told me that he cleaned his dirty **** K&N filter and removed the resitrictor plate. He claims the car feels a little faster now. I predict he will hit 210+ on his next dyno attempt after we do a few more tweaks to his car.

 

Your email address says it is not accepting emails.

Oops read the wrong sig.

He's basically got the same mods as I do (I have a udp which gave no gain on the dyno) and he may have cattman's muffler - at least that I had for the dyno. These are pretty good comparisons.

 

I agree.

He has a full Cattman catback.

 

I speculated that a long time ago. Also, they won't notice unless they are a 5spd. The autotragics don't even shift at redline.

For a while, I didn't even know mine was broken - it took a run on the highway against another max to confirm it and poor track times. And that's with a 25 hp loss or so at redline.