How about those with lower CR builds. I'm assuming the piston has a deeper dish, so would not increase valve travel clearance?

With Superchargers, there is a lot of blow through through the heads and makes it difficult to build pressure. Reducing the overlap and running a less aggressive profile will allow the SC's to get boost up quicker. Don't quote me, but I don't think turbo's have this same problem. It's also a big reason why long tubes weren't making the same power as a stock header because the heads and exhaust were too efficient. It made more power per lbs of boost, but not enough boost to make more power than the stock headers. I feel being able to control VVEL will be a big deal for supercharged cars. Maybe we can reduce overlap to increase pressure, and open it up progressively so it gets top end efficiency. Just a theory, but it sounds good lol.

Yep, there should still be some advantages NA, but FI greatly changes optimal valve timing. The ideal angle will change significantly as you force a greater volume of air into the cylinder.

Essentially, as I understand it, you want just enough overlap for achieving peak torque -- wrong timing means you just lose boost, blown out before it has a chance to build peak pressure.

With turbos I believe you want as little overlap as possible, as you want to get exhaust gasses flowing as much as possible. I'm more familiar with SC's, so someone correct me if I'm wrong.

Hmm, i was actually told the opposite. I had met some guy with a high horse power Z, and told me he supercharged his Z because the VVEL made turbos less efficient than a supercharger as far as reliability goes.

Dont hang me for this, just sharing what i was told lol :tiphat:

which actually made me re-think going TT. idk, :shakes head:

NP, I was talking to Mike@GTM over the phone about it and my long tubes. It's what he told me. Not the VVEL tuning piece, just the blow through effect and long tubes being too efficient. Likewise with a high flowing exhaust. The heads on the 370Z flow really really well.

Firehawk said it well,plus saved me allot of typing.:icon17:

All of these comments about blow through would be perfectly valid if we were talking about a system that does anything to the exhaust cam.

Until the variable phasing on the exhaust side is tunable, I don't see how it's relevant.

I don't see how holding the intake closed until the exhaust has closed would net you any real benefit since you'd be waiting until the piston was already on it's way back down before you open the valve. Surely any small gain you get from preventing blowthrough would be offset simply by there being far less time for gasses to enter the cylinder?

I mean, testing and time will tell, of course. Maybe they can work some magic?

Reducing the duration will increase pressure because less air is being blown through. With boost pressure just being a measurement of resistance, being able to modify how far and long the intake valves open should effectively change how and when the superchargers are reaching peak efficiency. The problem is there is too much overlap. The combustion process is still happening as usual, it's just when both the intake and exhaust valves are open, it's open for too long and reduces pressure. Getting more pressure built up on the intake side should allow more air to be pressurized in the combustion chamber when the intakes do open. Sorry if I'm talking in circles, I'm just trying to hit all the angles.

You could, in theory, make a funky intake cam profile that would work under boost, the problem is that it would be awful off of boost. Like, be a total misery to drive at anything less than 3/4 throttle and up.

Retarding the intake opening would make for some serious drivability issues, if taken too far (read: far enough to make any difference).

This is all in my estimation, so feel free to prove me wrong, GTM!

GTM hasn't talked about VVEL tuning with me, just the blow through effect. I have no idea if they tried tuning VVEL yet. I have no idea what the tables would look like for VVEL, but I imagine it can be tuned for all types of driving, NA, or FI. I wish there was more public info on the topic though.

so what would happen if we tune with the June Cam's ?

Exactly... Don't know why this phase ain't available to users to try to mess with. I mean if companies don't have time at least unlock that portion of it for end users to do their testing.


No one knows yet..... Only three known places to have it installed is the JUN team in Japan which has a complete high compression build, Germany's car which is built but no other updates than what is posted here and finally Navyboy916 here on Guam with a GTM head build but there is no access to Dyno here on Guam and he only gets Etunes from Uprev.

From what I just posted Uprev says they are not offering any VVEL tuning ATM so I don't see him getting any (VVEL adjustments) and even if he did get any. There would be no dyno to compare numbers before VVEL tuning and after VVEL tune.

so... we are at the same point where this thread started.

Well, lets see what Ecutek has to share on this. Allegedly they can access the VVEL target tables whereas Osiris makes their changes in a more indirect way.

IMO VVEL control will be what makes or breaks ECUTEK's chances with the 370Z crowd. I'm sure I'm not alone in saying that if they can prove noticeable gains from the VVEL tuning even on NA motors that a number of us with Uprev will at the very least consider going to ecutek.

Well even if they produce gains, I want to see cars that have their tune after a few months, maybe even a year or so to see how they hold up. That's great if you can "re-invent the wheel" as they claim, but that doesn't mean the wheel rolls straight.

I'm not hating by any means, I hope they have figured it out. I just want to see a few rolling around for some time safely before I put mine under the knife again.

If they'd work with someone who builds cams there would be no guess work involved. Creating a FI profile wouldn't put anymore stress on valvetrain parts than what is already present.

So long as there's no knock, no one is revving so high as to cause valve float, and there are clear safe max values to avoid piston to valve contact, at worst they'll see no gains and at best they'll see all the gains I've been hoping for.

I'm hoping they can also confirm or refute whether the Nismo ECU's have same or different VVEL target maps as compared to non-Nismo. I've been clinging to the hypothesis that they are different for ages now with no clear answers...

EDIT: nope, apparently same VVEL -- I stand corrected http://www.the370z.com/tuning/84786-...ifference.html

That is a good question.

I would say they are differant b/c I had my SC kit on my sport/touring and now my Nismo and my Nismo make more power across the whole RPM range and over 35 rwhp more.

With the same dyno, gas, ambient temp. ?

Same dyno,same gas,same time of year but I noticed as soon as I started driving my Nismo I could tell it was fast right from the beginning.

I've typically found in comparing stock nismo dynos to similarly modded AND tuned non-nismo Z's, the non-nismo Z's need TP's to make even gains (all readings from dynojets, using SAE correction, so easier to compare given the stability in dynojet readings across units).

Also, modded Nismos tend to fare better than similarly modded non-nismos, which is consistent with your own results.

That suggests there's more going on than just fuel, spark, and exhaust, but again, what we really need to see are the tables (or at least get a report from a tuner who can access them).

To me, that points to the one variable no one has been able to touch --VVEL.

But, that said, there's less data on Nismos because there are fewer Nismo owners...

So, it remains an open question... :stirthepot:

I definitely believe it is the VVEL ,knowing that non Nismo and Nismo engines are the same.

I also believe the VVEL tune is the reason NISMO's have a bit more power. From what I understand the only thing you can control at the moment with VVEL tuning via UpRev is the cam timing. I've had the chance to study the VVEL with my engine builder and tuner, as my motor is being built at the moment. If we could figure out how to adjust the actual cam lobe (as the OEM ecu already does) we could really get some power out of VVEL tuning. It's very cool how the solenoid controls the cam lobe. I want to say it's somewhere around 120 degree adjustment range, less lobe to more lobe. Problem is I can only control it with my hand on the work bench at them moment :/ hopefully haltech or one of these other tuning companies can crack it soon!

Have you seen the tuning thread where EcuTek apparently has full VVEL control?

Seen the thread where they claim this, yes.

There's yet to be anything posted that proves they can control it or, more specifically, get anything out of being able to control it.

Sub'd for info

Ditto


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Sub'd!

got really excited at those last few posts about nismos........ just to read 24 pages of rants, complaints, **** waving and nothing new that I didnt learn from page 1........ omg please just crack the F'ing thing. These cars have been around for 5 YEARS now. Pretty sure its a ******* lost cause by now. With nissan considering its next gen Z in a few years.....

hell in 5 years we could have trained ourselves our very own the370z.com sleeper cell to go work for nissan, had him promoted 2-3 times by now, and able to just simply tell us the secret. I mean seriously, how hard can it POSSIBLY be? maybe what you need is less gear head, and more nerd up in there. Every type of code/programing ever written regardless of their outward appearance has logical, predictable, and sensible pattern. Whether its talking with 0's and 1's, electrical pulses, P2, P2, code WHO CARES its all the ******* same principles. Im not claiming its simple. I know damn well how many complex systems the ECU is juggling, and its probably tough to find....... but holy fuckin ****, its not 5 YEARS X 3+ TUNING COMPANIES worth of hard. Im calling ******** and going to pretty much put out there that im 99% sure its a back burner priority. That they havent focused undivided attention in the least. When we get updates about something every 2 weeks to a month, and have to hear about business trips and how they "randomly" work on something it puts up a huge ******** flag that says lack of effort in giant bold red letters. I think some people are under the impression that this is being worked on by a large group of people non stop with no distractions and a large budget but its not. its probably a handful of people that randomly work on it every other week without a budget to so much as buy a god damn extra VQ engine or two to test this **** on.

Bet the NSA has already cracked it. :stirthepot:

also would like to point out that the post right before mine was in JUNE. Thus further supporting my point that the knob is set in the "take our ******* sweet *** time" position. Wish people would stop claiming on this forum they are working on something and then drop off the radar. Its happened on more than one occasion. They get everyone's hopes up, just to disappear and be replaced by the next SO salesman waving his bag of hopes/dreams/magical ponies.

I'm guessing the answer is "no" -- but:

"Any updates with any software, that clearly shows gains clearly attributable to VVEL tuning?"

nope just new rumors for Uprev

My tuner checked his stuff and told me he has full control. How can I find that out more? Question him some way?

Ideally we'd want to see some before and after dynos.

Fueling and ignition will probably have to be tweaked with VVEL is (meaning you can't change each variable independently of the others), but a maxed-out tune with stock VVEL setings vs. one with adjustments to VVEL would tell us what we want to know.

I read that Dynotronics has adjusted this and made power ?
Still haven't seen a dyno tho. BUT if I choose to go ECUTEK I will let you know .

source?

we are playing with it on a FEW SELECT customers, and on the dyno, but I have not found any earth shaking torque increases with it,,,,,yet.