VQ20

Wasn't sure if this is the right forum, since this will affect alot of guys across different years, Greddy has introduced a new piggy-back to tune Nissans CVTC and other manufacturers valve timing systems.

Check out the link: http://www.emanageforums.com/forums/...read.php?t=579

Would be anxious to see what this would mean for those running VQ35's and others with vtc.

gtr_rider

iTrader: (50)

I think this will serve better purpose in the All motor section, thanks for the information!

nismology

iTrader: (8)

Great option. Only problem is that it's not a substitute (i.e. V-AFC for S-AFC) for the EU, it's an add-on. $$$


And i wonder if it can control the Nismo VTC pullies...hmmm

XeroX

iTrader: (13)

This may be a stupid question, but for 4th generz that have done the 3.5 swap, could this be a possible mod to avoid having to modify the cam setup (cam spacers...etc)? Im assuming no, since this will probably run off the 3.5 ECU rather than the sensors...but i figured i would ask...

Also, dont most aftermarket cams for the 3.5s completely get rid of the variable cam timing crap anyways? Doesnt this kind of seam like a waist of money in that case? I understand its easier to istall something like this compared to puting in new cams...but....

scrhale

I am pretty sure that VTC availability is strictly dependent on the timing case ... not the cams.

nismology

iTrader: (8)

No. And it's not crap. I'm fully confident that the only reason some people "dislike" the concept/technology so much is because they can't retain it on their swaps. Simple.

eng92

iTrader: (3)

No actually it is the exact opposite.

If you have fixed cam timing that is optimized (for power) to work with higher lift, longer duration aftermarket cams, your engine will either idle like crap or not idle at all. You would need to set the idle at something ridiculous like 1500 rpm at which point the car is no longer realistically streetable.

Optimal cam timing (for power and streetability) varies strongly with engine rpm whether you have stock or aftermarket cams.

If this Greddy system is indeed what it appears to be, I will be buying one.


If it drives the solenoids directly and uses the cam sensors for position feedback, an extra 15 (crank angle) degrees will not be a problem.

I guess the problem will be determining the timing limits for higher lift, longer duration cams. With the additional 15 CA degrees of cam timing available, piston to valve interference may become an issue.

Fred Allen Burge

I'd be suprised if this actually drives the solenoids directly but rather modifies the cam signal to the ECU to fool the ECU, much like an AFC does for the MAF. But, if it is indeed a standalone controller this should be interesting for those running a standalone that doesn't support VTC yet (such as MegaSquirt). I haven't read the link yet.

Fred

XeroX

iTrader: (13)

Hmmm...Do most people with the 3.5 swap experience idle issues like this? This would be new information to me as im planning on doing the swap...

Im not really into the terminology like that so forgive me if you have already answered this question, but again; could this be used to avoid having to disable the variable cam timing with the JWT spacers for us doing the 3.5 swap?

eng92

iTrader: (3)

No, they are not having any idle problems AFAIK. But note, I specifically used the words "optimal cam timing".

Idle problems will generally only arise with some of the more aggessive cam grinds.

No this system will not change anything in that regard. Disabling the vtcs comes about as a result of using the A32 timing equipment (sprockets, covers, sensors. etc.) in order to accomodate the A32 ecu.

You would need to adapt the A32 cam sensor onto the A33B timing cover and give it a suitable target to read on the vtc sprocket. The crank pulley sensor would need to be mounted on the cover as well. This would give you the necessary inputs that the A32 ecu needs. However even after all that work, the A32 ecu does not have any outputs to drive the vtc solenoids. Therefore if this system is just a simple piggyback that modifies the cam signals, you will still be out of luck.

eng92

iTrader: (3)

Unfortunately I would have to agree with you.

If that is indeed the case, it will be interesting to see how much of a positioning error that the ecu will tolerate before it shuts the vtcs down instead of correcting.

nismology

iTrader: (8)

Maybe it modifies the signal TO the VTC solenoid valve and FROM the cam position sensors as well.

eng92

iTrader: (3)

The pwm signal to the vtc solenoids is not like the analog signal from a MAF that you can easily just add or subtract voltage from. In this case, for full cam timing control you would need to be able to create a signal when there is no stock signal present. (ie. start advancing the cams at a point earlier than stock.)

To do this, the v-manage would need to have its own pwm driver circuit built-in. Although similar to an injector driver, in that it is pulse width modulated, the frequency is fixed (ie. independent of engine rpm) and is much higher. Better drivers would also have an even higher frequency dither signal superimposed on the base signal. This promotes better valve position control by reducing stiction (sticking friction) problems with the valve spool.

The necessity for modifying the cam signals will be a requirement no matter how it achieves the cam timing control.

If vtc solenoid control is by v-manage, there would need to be a cam position learn function so that the v-manage can output a signal to the ecu to make it "think" it is still in control. This would be a function of rpm and load. The v-manage could then control the vtc solenoids directly and use the cam sensors for feedback independent of the ecu. This type of system would give us the most flexability.

eng92

iTrader: (3)

Well it took a while but they finally have an english manual available.

http://www.mohdparts.com/emanage/man...age/index.html

braxsusriely

i think when they produce a price for the nissan model i'll be sure to get one. I'm already in the process of putting together my MegaSquirt

nismology

iTrader: (8)

Nissan model? It's already for sale and is compatible with nissan CVTC and NCVS.

maxspeedse02

iTrader: (7)

This unit is about $500 on ebay on top of an EU, couldn't you get a full standalone unit for a similar price to control the same things? UTEC? I don't know much about this but that is a grand just on piggybacks

nismology

iTrader: (8)

Nope. You won't find a standalone that can control CVTC for under $1000. Not even close. The only 2 that come to mind (MoTeC M600 and Hydra EMS) are closer to $2k. The UTEC (a piggyback BTW) costs like $800 on its own brand new and doesn't control CVTC.

Gotta pay to play, my man.

maxspeedse02

iTrader: (7)

I didn't realize the UTEC was piggyback must have mixed it up with the M600.

I've been playing around with the idea of upgrading to the EU but I'm not really informed about everything it can do. Guess I have some reading to do.....

NmexMAX

iTrader: (22)

TS charges $535 for their remap, and it does modify CVTC, but it's pricey. and you cannot 'tune' it on your own. Stuck w/what they give you. (Z33 map)