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Discussion Starter · #1 ·
When engines have failed on the VR38 which cylinders normally go and when rods have bent which cylinders are these common to happen on.
Reason i ask is i have been doing some calibrating on the VR38 for a whole new breed of engine control on the GTR and found some interesting results last night when setting up the Closed loop individual cylinder knock control.

Below is a log showing the knock traces from each cylinder


Red is Cyl4 and Dark Blue is Cyl3 you can see the difference compared to rest. The centre cylinders are always louder so gain has been adjusted to suit already which is due to the knock sensor placements but even so the centres are always first to knock and its not just because sensors are placed in centre of block as it knows which cylinder its firing based on listening to the correct Freq in a set window after each event has occured so shows that maybe the centre feed intake design favours the centre cylinders or its just purely down to that the centres run hotter due to cooling designs.
Will back up when I get all 6 egts in the manifolds.
Just to note the stock ecu regarded none of the above as enough to pull timing as i have left the stock in to keep the canbus happy and monitor knock as a extra sanity check (will be removed next week when canbus patch is applied
)

But interesting enough now the standalone ecu is running the engine and injection has been set to match the larger injectors properly it enabled the engine to take more timing and produce the below.


Ryan

BTW before anyway asks why its lost power below 2400rpm its due to how much time the load it kept against the engine at the beginning of the run. The longer its held the more boost its creates.
 

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There are a few impressive looking spikes on the #4 trace (esp just before 10s), but I think your gain is still a bit high considering the overall noise from that cylinder. How do the gains you've set for your graph/display/logging relate to the noise thresholds the OEM ECM uses for knock control?

From previous testing I also found that even an apparently high impedance op amp (10Mohm claimed) input can drag down a knock sensor signal, so were you using the OEM knock sensors for your logging at the same time as the OEM ECM was using them for knock control?

The OEM ECM knock control doesn't appear to have any dynamic adaptations like say the 4G63 has, but I believe it is still gated and filtered. With a lot of internals the centre cylinders just saturate the OEM settings and you end up at 65535 which disables the knock control on that cylinder. Perhaps aftermarket you can get more dynamic range through gain control.
Certainly is and it resulted in the first knock event step calibration to be more aggresive in the base map to remove the spikes but stock ecu didn't care even with the Standalone removed from the knock signal but tbh there was no need to as it has no effect on the signal after checking with a scope. See i believe its not gated as i watch the stock ecu correction constantly via the check light for any correction and i every so often see it correcting in transient vacuum situations on gear changes where background noise is resulting in similar freqs

The gains on 4 are maybe abit high but when an engine costs over 10,000 i would rather be sure for intial setup it reacts quickly on the event even if it is background noise.

I have found this alot with the stock ecu control of knock after checking with det cans, grab some cans and load up engine at say 2500rpm your be surprised what you hear and what the stock ecu does. Still surprises me to this day that the e-mail tunes and even custom tunes result in no tuners monitoring knock apart from on the stock ecu. I certainly wouldn't relie on this with a customers car.

So which cylinders have been known to bend rods guys?
 

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Discussion Starter · #11 ·
my first engine was number 4 OEM ENGINE stock, my second Engine we shipped it back to JAPAN for them to check.(it was due to hydrolock due to liners)..

so what your saying is the COBB/OEM cant check for knock on each cylinder ?

will the S8 Ecu be able to do this ?

can the S8 offer a engine cut say if there was an issue with the fuel etc ? ie pressure or something

SUBSCRIBED
I can't comment on how the stock ecu (cobb/ecutek) determines what is knock but im sure it's not gated after my findings. If it did trim based on cylinders Cobb/EcuTek would have found the cylinder trim parameters. On the S8 you can log each cylinder at up to 1000hz which is filtered, gated and fully adjustable to suit differences in the combustion chamber which I imagine alot of the High hp VR38 have had done. If the high hp engine builds in the GTR world are changing the Combustion chamber then I would not be relie on the stock knock control any longer and ensure det cans are used. To be honest if you are tuning the vr38 right on the limit of the fuel I would ensure the tuner has det cans on.
Considering that the stock ecu did nothing even though we were picking up knock on 4th is worrying…. I did bring the engine to the point where the stock ecu saw knock in lower boost areas and it was then picked up on a lot of the cylinders on the S8 and produced a serious spike!.

BTW the gains in power we found were purely down to being able to add more timing so that says to me a few things are not right with stock ecu with bits that are not stock but don't want to give to much away ;)

S8 of course has individual knock control as you can see it working in the log when it pulls timing just on 4th, be it the first event step needed to be larger to remove the tiny knock events on 4[sup]th[/sup]. But this standalone is what keeps 800+hp engines running constantly at full wack for over 24 hours in leman so it has a lot of strategy additions to the knock control.

Yes Engine trips are one of the big things that it will bring to the VR38. Will monitor fuel pressure relative to manifold pressure and trip/trim fuel to fix issue instantly. Same with oil pressure say oil pump fails or big leak and pressure drop it trips engine. Plus actually have proper wideband lambdas fitted and running in closed loops.

List is endless with ability to have over 30 inputs of extra sensors to trim say egt on each cylinder etc but will all be released soon. Please note this is not a system like the Proefi or haltech which requires stock ecu still and a complete replacement which joins the canbus system and actually applies torque reduction on gear changes unlike the haltech/proefi which has resulted in a few broke boxes.
 

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Discussion Starter · #13 ·
This from my email to you 30 Aug:

"I am always recommending det cans to allow tuners to calibrate the knock control especially with cams, forged pistons etc. Few seem to make it work, and some have strange approaches such as pulling plugs and looking for drops in torque on the dyno. Personally I prefer to listen with det cans, but I don't on my own GTR as I'm quite happy with the OEM knock control as I have a completely stock car except for a tune and I really like its refinement, smoothness and reliability in this spec. I used to use them heavily on my Subarus as the OEM knock control was not so good and the car was much more modified, plus it was easier to hook them up and listen whilst the car was driving. I didn't persist in looking for a place on the GTR block to hook them up because of the low mod state of my car, but if I personally were to calibrate high power GTRs it would be the first thing I'd do. I can usually hear knock without det cans as I'm quite attuned to it from previous calibration, certainly I could always hear Subarus knock by the time they hit a red on the old knock links. I've never heard a lightly modified GTR knock, but a lot of people mistake noisy bell housing bearings/propshafts/transmission noises for knock on GTRs."

I couldn't find a way to use my old mechanical det cans because I couldn't easily route a hose through a door or grommet in the firewall as easily as I could on Impreza/Evo and without a dyno personally I had to get the bonnet/hood closed to load up the engine. I tried a Knocklink and the signal was quite low on the top of the inlet manifold. If there is a way to piggyback from the stock knock sensors without affecting their readings by using a high impedance op amp, it could be an interesting product, with options from then to simply use headphones, record the audio, and various live or post processing options, or indeed a full Syvecs.

I'm probably stating the obvious pointing this out to you Ryan, but some think the ECU is registering knock when it is merely crossing the load threshold for knock control and the previous knock value used in the knock control area is reused, not signifying a new knock event. It depends how the knock is reported in the OEM ECM logging software, not sure how the software you're using does it, but if the report of knock is only in degrees you'll be missing a lot of detail.

You have an interest here is promoting a new standalone, and good luck to you as it will be genuinely interesting, but if we are going to say that the OEM ECM is having a substantial number of false positive and false negative knock events that result in significant loss of performance vs safety, and infer that email tunes are damaging engines, then better evidence will be convincing. I'm not saying the ECM is always appropriate in its knock control, but that I'm happy with what I've personally seen of it, and a few ticks heard in det cans when you think the OEM ECM should have done something, and a few knock events when you think it shouldn't, and comparing that with a rate of damaged internals from a forum straw poll is of interest value but not conclusive, but I'll be the first to change my opinion based on a more cohesive argument. Perhaps at this stage you're trying to ask the interesting questions or are you stating a marketing or technical position that OEM knock control is damaging engines?
I remember your e-mail John and i know that you know what your doing when it comes to calibrating mate as if Pat/Merv say you are good i listen. Look there are lots of cars out there on e-mail tunes etc so i havn't really got a leg to stand on saying it wrong at present but if these e-mail tunes etc are finding peak torque based on the fact that the vr38 is knock limited and taking it to the point of knock i bet and then back off. If that the case then i just saying that the ecu saw nothing when we saw stuff on 4th and might explain why thats the cylinder which goes first...

Im just interested John as like your self get a kick out of this stuff, Look jump on a plane in jan and come do some testing with us if you wish with the S8 plugged in our testing piggyback loom and a Cobb on it. You can help us find the last CanBus bytes also for a few items


Ryan
 

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Have you access to the OEM ECM per cylinder knock noise adjustment thresholds? Knock on any cylinder drops the knock value by 307 and affects all other cylinders, this is why we only report one knock value because it affects all cylinders. I'm sure you could get a little more performance by waiting to retard each cylinder when it knocks but if you had high cylinder pressures you might prefer the cautious method of retarding all? Nissan state that the VR38 is not designed to knock in normal conditions running its rated fuel, so their knock control is a backup, perhaps this is why they retard all cylinders when only one knocks?
I have not looked at the stock threshold as it not viewable in the Ecutek software

Can you see what frequency it is listening for or change it to suit different engine configs, if it even does this?

Also i imagine it does not listen in a set window like the S8 to remove background noise if its becoming saturated as standard?

BTW John the extra power did not come from allow more timing in cylinders which were not knocking but down to a calibration which greatly improved the combustion stability and aloud even more timing over Stock but increased the torque just without touching the timing. More will be release when its out to the market but there is something you are missing on the stock ecu controls at present.

Ryan
 

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Discussion Starter · #19 ·
+3

Improved combustion stability!? What is that?? Is it measurable? You mean you have somehow increased the threshold for knock?
Anyway, what John does not know, is not worth knowing
On a Stock car it wouldn't make a difference as nisan would have got it right but on a modified engine which has changes to allow for over 600hp then it definatly wont be right any longer on the stock ecu with a cobb or ecutek i can assure you.

Ryan
 

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Discussion Starter · #20 ·
John is a very knowledgeable gent who i will listen to anytime but he is not a full time calibrator who works alongside with a leading world engine research (http://www.aerltd.com/) company setting up different engines daily on engine dynos/chassis dyno. In fact he does not believe in Dyno tuning

Making changes to a Rom file is not exactly calibrating an engine like a standalone espically when the stock strategies do most of the work.

Ryan
 

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Injection timing is a PITA to find and adjust in OEM ECUs if that is what you mean. Its value depends really on your injector duty cycle, if you end up running them hard whatever size you put on, then it hardly matters. If you use massive injectors and tickle them I'd expect some gains might be possible. I played with it before on MoTeC on a Subaru and couldn't tell any difference, but my injectors were probably nearly wide open anyway ;)

I can't make enough money out of engine work that is why I only do it a few hours a week. Maybe if I had my own company, but I don't want all that hassle and setup time, it would ruin something I enjoy and can drop when I get bored. In terms of ease, I'd much rather be calibrating standalones than reverse engineering OEM stuff though, there is a huge amount I don't know but I do a lot more than changing a ROM file but re-engineer the strategies which is why we have our own boost control, realtime mapping with quite sophisticated map switching, SD etc. Reverse engineering makes your head hurt in a way that few other disciplines do, perhaps that is why I have particularly enjoyed it during the early discovery phases on a platform, but there are practical if not theoretical limits to what you can achieve by reverse engineering and rewriting stock ECU code. I first started it open source on the Evo as I found that at the time most OEM remapping solutions were simply altering tables rather than rewriting program code to remove limits and do new things, and I also didn't find that many standalones had the refinement or price I wanted, so it was fun to make stock ECUs do things that others thought they couldn't and then it followed with the GTR, but it has been mostly due to "bloody mindedness", hopefully I've left you some morsels for running standalones on and you'll be able to firmly demonstrate why, when and where they will come into their own for the customisation and control that is not feasible to achieve on an OEM ECU in a reasonable time, but when the OEM ECU can run 8s and drive nicely you have a little work to do to prove your advantage, but will clearly be in a different league to the Haltechs and ProEFI stuff. I do believe in dyno tuning, for people that want dyno numbers ;) and also some specific tasks, but as a jumped up amateur hobbyist I just don't have the access, but let's see some records fall before I worship your dyno ;)

With AccessTuner Pro there is a calibration available for the noise level per cylinder and engine speed, which allows quite a lot to be achieved with knock control all the way to turning it off if you need to, or just on some cylinders at some engine speeds. I expect we'll see it in the "other" software soon enough
Frequency is not adjustable but I expect uses hardware filters rather than any evidence of DSP or adjustable analog filters.
Nice post John

You got there in the end on Injection timing, it did play a big part aswell as a few other things but the Syvecs is not aimed for the level of spec of the Demo car its more aimed at GTRs running past 650hp where the added safety features and level of control that the syvecs brings ensuring the VR38 is fully protected and undercontrol.

I can imagine INJ T will be a PITA with rom tuning and its something 95% of tuners never touch with standalones!

Reverse engineering the canbus has been tricky but well worth it as we can now keep the flickerbox and everthing else happy and Nissan would never know the syvecs has been on there which might become a popular seller for new modified cars which have warranty.

Did you know that Ignition timing, Lambda, Boost and a few other bits are sent to the flickerbox (black box) Being able to adjust the can messages to this box becomes very useful ;)

With a reflash nissan will know for sure even if a standard rom is put back in as they can just look at the flicker boost and see its been running more boost


Happy new year and feel free to pop down and catch up with Pat and Myself any time if you want to have a look at syvecs.

Ryan
 

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Ryan, that final point is somewhat strange.

You say the Syvecs is aimed at the top end highly modified GTRs, yet suppose that altering data sent to the Flickr box would be useful.

I'll eat my hat if a high end modified GTR running a S8 tune has any warranty work authorised by NIssan only on the basis of Flickr data, and not the glaringly obvious wholesale change made to the cars engine/gearbox.

That aside, any new tuning solution is always welcomed and I wish you luck.

When can we expect a working end user solution for the R35?
I see your point and reworded my post


When i state highly modified i mean past the point of 650hp where different turbos and many other aftermarket parts are fitted. Offering facilties such as trips for Relative fuel pressure or oil pressure drop etc and much more will then give the owners even more piece of mind. A full dealer on here will be able to advertise all the benefits soon though.

My point of the flicker data was just a general one saying that as the Syvecs has fully adjustable Canbus which now works happily with the GTR System it would be very easy to make the flicker box see clamped/Mali values which the ECM sends. Might become useful for a 2011 owner who wants say abit more power etc and not worry about cover. Obviously the car would have to be put back to stock before it went it but for say a new gearbox it might be worth it. Only thinking out loud on this at moment tho.

Thanks for kinds words and it will be released soon in the next month.

Ryan
 

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Discussion Starter · #36 ·
here is the problem i see, everyone needs a cobb due to the transmission settings it can do in the 006 version... so why would i spend loads of money on ur product and a cobb 006, when cobb 006 and a custom tune will be much more affordable and have transmission settings/adjustments. Do you also have these features like the cobb and ECUtek? iirc ECUtek now has some of the features of the cobb and are working on more tcm stuff like adjustable shift points and LC on all the models with other LC features (not sure if this is all in beta or alpha or what not). Those people with haltech and proEFi iirc also require the use of the cobb 006 for transmission things (am i correct in suggesting that (from what i read on the forums anyway)?) Dodson iirc are working with some ecu maybe its MoTeC for a full TCM control and have been testing it heavily from what i hear.

I see your ECU has many features that some people are looking for and very few people to setup and tune all those features (as i have read a few of the threads online about Syvecs). I see some advantage but not the full package, unless your taking advantage of all that unlocked goodness and using it to your advantage. would like to know more about traction control and if you can edit anything with that or not and what the changes will do in real world.

I think adding the whole black box deturent thing is a moral issue... maybe its just an advertising thing for you and leave it up to your customers to do the right thing, nissan's not exactly honest with covering warranty work when it should be covered all the time either.

can you give me an estimated price braket of this product and a custom tune from someone who would be able to utilize all the features on a 1000hp gtr, including the ecu and any neccessary hardware that requires the s8 to run properly with full functions for the gtr?
Hi

Thanks for feedback it is very useful to hear what others are thinking :thumbs:

The syvecs is now fully running as a Standalone on our test car while keeping the Can Bus system completely happy. All Dashs work and we have taken everything that we would want of the Canbus also for fully adjustable traction control based on steering angle and Lat G. So in answer to your question regarding TC it is fully adjustable which can be adjusted to achieve different amount of wheel slip by either the use of an 8 Position Pot or via using the cruise control up and down buttons. It also can be used to target a certain amount of Lateral g in corners and correct the engines torque to adjust for it.

Also fully adjustable launch control with proper retard for full boost of the line and then have complete control of the ramp in torque which allows you to control your engines Torque based against long G or road speed for gaining a perfect 60ft everytime. This again is fully adjustable and the logging for this is fantastic espically for drag racers.

All the actual, desired torque values, status signals etc are outputting correctly and fully adjustable to the stock TCM so we change clutch clamping etc which is all tested.

But to be honest for how much it costs to just pop on a licence for the TCM ecu with ecutek we will recommed that which soon will have full control of the gearbox and save us having to replace the stock tcm like the Dobson/motec package is doing which adds to cost hugely!

Also have full control over the Fuel system for controlling both pumps etc and have trips to protect engine on relative fuel pressure (Fuel pressure against Manifold pressure) If one of the pumps fails and drops pressure on boosts it instantly trips!

Proper NTK Lab grade widebands which wire straight into ecu for correct a/f ratio not estimated on stock ecu due to the heater controls of the lambdas not being adjustable and heat changing massively when removing the cats etc.

Fully adjustable filtered knock control to suit any Combustion chamber size not relie on a Strategy that is designed for stock size with cast pistons.

6 Egt inputs and trimming to suit...

Fully adjustable sensor inputs for monitoring everything including trips for like oil pressure, turbine speed sensors, crank case pressure etc

The benefits are actually surprising the more and more i go over them but a full release will be done soon with a few surprises.

But the datalogging is one of the massive benefits and one of the main reasons for doing the package for cars which need to be monitored constantly in the pits and have limiters etc to comply with race series.

Cost wise will be released by trader

Ryan
 

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Discussion Starter · #39 ·
Ryan, i dont see any dealers on the syvecs website for the USA... do you know of any that will be certified in the USA in the near future?
We are currently in talks with one of the biggest tuning companies in the USA at present who will certainly be up for the task of the Syvecs.

Plus i will when all finished make up a full spec and feature list which will send out to a few of the big GTR tuners along with software to tease them


Dont forget though that the package will come with a Rj45 ethernet connector for connecting to the units and i daily dial into ecu's over the web to tweak and train users.

Ryan
 

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Question... big thing that people have been trying to do is get the gtr faster than 217mph
there now is a
ALBINS 230 MPH FRONT & REAR PINION

To allow for those, but no one knows what this will do to the electronics of the gtr. iirc its 2.7:1 front, 3.4:1 Rear Ratio. Do you think with the syvecs that this would be less of a problem if all the aero was sorted out?
Will Answer your PM now, sorry for delay i have been flat out sorting stuff at a big show we have in the UK at Present.

With regards the Final drive changes i can imagine the stock traction control and probably the 4WD unit will not be happy with the differences in speeds but the only issue we would have would be with the 4wd unit. Dont forget though we could just add corrections on the Can Bus for the parameters which will need to be modifed to keep the 4WD unit happy like Wheel speeds, Output and input shaft speeds etc

Another big benefit we have found is that the stock ECM has a maximum torque reduction amount on gear changes which for big power car might cause fairly harse changes on at WOT. We are currently making the Torque reduction fully mappable for Ramp out, and Ramp in to ensure a smooth but correct amount of torque to be pulled to keep the box in one piece for longer.

Ryan
 

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Discussion Starter · #44 ·
Just a Small update is we are currently working on the final Torque Actual tables and Adjustments to this via the S8 to accommodate for Bigger power GTR. We doing some small tests for Ecutek also regarding the torque values as we wish to further help improve the new TCM support work they are pushing hard on.
 
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