Vas_Z33

iTrader: (39)

Whats up fellas!

It sure has been a while. Never thought I'd be in another Z again, but here we are with twins haha. Many of the OG members from my old days on here have not logged in years, so I hope there is still some knowledge in this board. I'd hate to take this issue to facebook lol.

The Setup is a Greddy TT with External WGs & EVC 6. Long story short-- I was going over the Z. Doing the plugs, oil, filter etc.. and I decided why not, let me run through the HKS EVC Stepping Motor / plumbing and make sure all vacuum lines are good. ( p.s- I am following the HKS Poppet Valve Type diagram as I am going over this. )

According to the HKS diagram ( See attached picture ) The Left 6mm Hose goes directly to the UPPER PORT of the WG's. The Middle 6mm hose, goes into a T ( 6x8x6mm ) that taps just before the Throttle Body, which then routes to the BOTTOM PORT of the WG. The Right nipple ( shown in Green trace ) taps into the Intake Manifold and Fuel Pressure Gauge.

MY PROBLEM:

This is where things just started to not look correct as I am following the HKS diagram and the current plumbing. If you notice on my picture of the Engine bay ( Red Highlight )-- The plumbing here is connected the same way as the HKS diagram, but they seem to be FLIPPED. Currently, The Left side of the Stepping motor goes to the BOTTOM of the WG port... The Middle nipple from the stepping motor, goes to the TOP of the WG port. The Right nipple ( highlighted in green ) plumbing is correct as it should. When I follow, goes directly as the HKS diagram states. The other 2, not so much..

Now, can someone PLEASE call me crazy and that I am wrong.. Would love some verification and advise from the wizards here.

0taku

iTrader: (5)

They do looked flipped and the vacuum filter appears to be placed differently also.

Does the system work? Or what problems are you facing?

Vas_Z33

iTrader: (39)

Thanks for the reply. I did notice the filter as well and was going to fix this too.

So Im not facing any issues per-say. The car cranks, idles, and drives great. However, I have not gone out of my way to go much in boost, only slightly ( not redline ) and it pulls/ feels solid. -- I just don't want to be facing any issues when I get a retune. Which is why Im going over the whole thing prior to a re-tune. Car made 380 on a Dyno dynamics @7psi before/currently.

-- I have been in-touch with the previous owner and he says that the plumbing has been this way.

p.s- The Z used to belong to @leemik 1st owner. The setup and Twinturbo has been the same throughout the life of the car, nothings changed except the clutch. The 2nd owner that bought it, said that he hasn't changed anything. Also, doing my investigative work and looking at old engine bay pictures of Leemik's setup ( see attached ) the plumbing is still the same, which technically is wrong, as per HKS diagram...

Im just confused at this point because it doesn't make sense.

bealljk

iTrader: (13)

what is the stepper-motor? is it acting like a boost control solenoid?

How are you tuning (meaning what ECU flash / piggy / standalone are you running)?

Are you 100% dedicated to the HKS stepper motor? Would you consider going with a traditional boost controller? or boost control solenoid off an ECU?

Do you even need a boost controller? why not run 8psi waste gate springs and possibly a mechanical boost controller? Albeit not as sexy but far less complicated?

I do the same thing ... I have about 500 or 600 miles on my car since my recent rebuild and I've caught two or three things that would have stopped a dyno tune ... always good to shake things out!

Vas_Z33

iTrader: (39)

Thanks for reply!

bealljk

iTrader: (13)

I should have known it was a boost controller - what else would it be!

If nothing is wrong than dont fix anything but you may benefit from a little ECU / boost controller refresh ... Emanage isnt bad but it's a pretty bare-bones piggyback ECU - I would say it's been elasped by three, possibly four generations of ECUs on the Z33 DE ... it definitely early 2000s technology.

You may be limited on what you can do with annual inspections and emissions in NY but if you can run a standalone and can budget the cash for it ($1500 to $3000) you'll gain many more relevant features. Look into the Haltech Elite or the Link G4+ / Link G4x for what some of the newer ECUs are capable of.

Any modern (2010 and newer) will have duty cycle outputs to run a boost control solenoid.

Im not saying it's cheap or inexpensive but it looks very complicated and prone to failure - especially all the vacuum lines running everywhere. one-way check valves, plastic T-fittings, etc. I have found (in my experience) making things more complicated leads to failures and break-downs. I've been around my 350z since 2005 and have been FI since 2007 and I have never seen one of these HKS boost controllers ...

I run a simple 3 port MAC solenoid hooked up to my standalone with a single port hooked up to my waste gates (I run a slightly different waste gates than a traditional diaphragm style - Tial for instance) and both open loop and close loop boost control is very easy to setup and control.

Big picture - you may not have much support on this particular controller as no one has experience on it.

Vas_Z33

iTrader: (39)

Many thanks for your input btw! and glad you're still active on here haha

Maybe I will look into the AEM tru Boost. I've had this in the past- I'd just hate to remove all of this, especially if it isn't needed ya know.

0taku

iTrader: (5)

Something just isn't right.

I'm looking into the manual as well and it just doesn't make sense.

Let's say the nipple pointing towards you for numbers 1, 2, and 3.

Currently based on the diagram, your order is 2, 3, and 1. So all three are in the wrong location. (This is assuming by the picture that the 1st vacuum nipple is post MAF, and the other hose leading to the FPR)





Now, this is just a theory and don't really have much evidence, but I'm wondering if you're just running off waste-gate pressure this whole time since you're only seeing 7 psi to begin with. It's hard to tell if it's really working unless you push higher boost ratings IMO.

The placements on the filter and t-fittings seem too perfect, but the hose placement appears wrong. Like, why would you have a vacuum filter on a hose pulling vacuum out of the stepper motor instead of towards the stepper motor?

Vas_Z33

iTrader: (39)

Ok, so looking at your labels for numbers 1,2,3... Number 1 ( see attached highlighted in green ) The plumbing for number 1 is actually correct. Follows the exact HKS plumbing that I attached earlier ( green ) . From Intake manifold -> T fitting -> 1 to the Fuel pressure gauge and 1 to the stepping motor. Also just to note on the stepping motor.. Number 1, is a 4mm vacuum line. Number 2 and 3 are 6mm.

However, Number 2 and Number 3 are wrong. They are flipped. You are also correct on the vacuum filter being placed wrong. As per HKS diagram it should be closer to the stepping motor.

To tell you the truth.. I am coming up to the same conclusion as you. Could just be running on WG pressure and this whole controllers plumbing was installed wrong to begin with and the first owner ( leemik ) never even noticed. Because again, looking at his old engine bay picture.. it is ALL the same plumbing as it currently sits. which is wrong and Makes 0 sense haha.

0taku

iTrader: (5)

I might be looking at it wrong. The hose in red, does the other hose lead to the FPR or bottom of the wastegate? I been looking at that hose assuming it was the FPR. Probably where the slight confusion came from.

Yeah, stepper motors kinda got obsolete fast when solenoids showed up. Can't argue with faster response (electrical vs vacuum)

They're actually not that complicated, can't say anything about the reliability portion. There isn't any one way check valves(it would actually cause more problems than saving if you look at it), although hoses are never a favorite.

The more I understand it the more I'm able to help figure this out. (the manual is pretty in depth of the product EVC6)

So, it would appear that the stepper motor gets fed pressure(on boost) from two hoses (the ones with the filters), while the other hose obviously feeds pressure to the WG to open it up.

The green hose feeds boost/vacuum to the stepper motor which in turn also feeds a signal to the control unit(display, w/e). The stepper motor (which uses like a teethed wheel, adjusts in small increments on opening/closing the wastegate by changing the amount of pressure) Pretty neat but not as good as solenoids sadly, which adjusts more accurately and faster.

So, by that logic, the EVC6 can track boost/vacuum since that one hose is setup right. Now for the other two.

Since it's switched, you're feeding positive pressure to the bottom of the wastegate. Essentially your wastegates are both just sitting there left open. The EVC6 will still read correctly, although you wont be able to adjust anything since the two hoses are swapped.

bealljk

iTrader: (13)

I dont even remember stepper motors but I came to the party late.


big sigh … back in 2012 when I was doing my first rendition of my greddy twins I made it overly complicated and the system failed due to an oil starvation issues …

I've since replaced most rubber / silicone vac lines with 1/4" aluminum tubing and AN -4 fittings … I just about replaced anything that could burn, melt, crack, leak, ruin my weekend with metal tubing and/or put fire sleeve on it. If it can go wrong, it will go wrong.

what are the 'vacuum fittings'? what the purpose of those?

Vas_Z33

iTrader: (39)

Yeah my fault from the red highlight, you cant see where it goes. I re-attached the picture again, you should be able to see better now and where it taps. You'll notice right under the BOV. Number 3 currently goes to the Bottom of the WG. Number 2, goes to top of WG.


That logic is right on point. Couldn't have said it better!

0taku

iTrader: (5)

Heh, I know the feeling. I went way over my head when I was trying to build a VQ33 frankenstein turbo build on a 240sx. (VQ35 block, vq30 heads) Still had a lot of kinks to it, but ended up selling it for a decent price. Pretty fun for a first turbo car project. Well, kinda fun....

When I used the Greddy Profec (the old school one with *****), it had a stepper motor as well if I think about it.

About the vacuum fittings, see previous post in the bolded area. Or was there something else?



Filter-wise, it should be fairly simple and straight forward. I'm sure you can just swap the two hoses so the filter goes directly to the stepper motor instead of the intake piping. (Not sure why the last person did that)

Vas_Z33

iTrader: (39)

Yeah just waiting for the k&n turbo filters to arrive today and was going to do it all at once. Route the plumbing correctly on #2 and #3 and fix the filters. I just cant sleep to plug them back in the way they are and be ok with it haha. I'll check the boost settings on the actual display and make sure is set correctly and not to some catastrophic pressure and go from there.

Should be straight forward. Many thanks for your input guys ( otaku and bealljk ) It's nice to get a 2nd opinion. it was driving me crazy and was not making any sense looking at the HKS diagram

0taku

iTrader: (5)

The one thing I’m worried about, is switching the hoses around with your current tune. I think with the boost controller, you’ll be able to get a more smoother/faster boost buildup vs running the wastegates stuck open. Because of this, the exhaust turbine doesn’t spin as fast and loses a considerable amount of efficiency. On the next tune with the same boost, you should be able to see boost a lot sooner.

If you play around with the emanage enough, you could do it yourself, but that’s up to you.

Vas_Z33

iTrader: (39)

Ok thank you for the heads up. Yeah I don't even own a windows machine and not much experience there with tuning Emanage. I'll be staying out of boost- I am in-touch with the tuner now and going over the appointment

0taku

iTrader: (5)

Nice! Best of luck!

leemik

iTrader: (2)

Sorry for the bump but holy blast from the past!! I haven't seen this car in 10 years.. Vas_Z33 are you the owner of my old Z now? Did you get everything sorted out? I'm curious to see what it looks like now

As for the vacuum wiring.. When the tuning was done I complained that I couldn't set the boost pressure.. They told me the car was set to max wastegate pressure and I shouldn't mess with it for safety purposes.. So this is probably how they did it. I think the motor eventually blew anyways and was replaced after I sold it...

I'm a little bit sad the clutch was replaced but I guess a full on racing clutch and flywheel wasn't too fun driving on the street..even though i got used to it

--mike

Vas_Z33

iTrader: (39)

Ahh theres the man, finally! haha. Yes sir. I had to go over everything once I got the car and found a few things definitely miss placed. Chased down the problem of the vacuum lines and rewired the HKS. They sure fu**ed that wiring up and was over boosting. Wired it correctly and is holding boost steady at 5psi now, but wouldn't go up. I am sure its in the settings of the EVC6. Now just running on wastegate pressure. So far so good. The tuner has been busy this year so hopefully waiting to getting it dialed in before years end. She still looks good though, same as before and well taken care off. I know the clutch was changed, but I think the engine lived to tell another story. Just hit 70K miles.

bealljk

iTrader: (13)

Happy the wiring got figured out! and beautiful pics!