Tomei Rb28 Pro Cams

[hspeck]

My car is running on Tomei RB28 Pro cams.

The intake and exhaust are both 270° and -10.25mm lift.

I was told these are high overlay cams.

According to the Link help menu:-

The Lambda/AFR Target Table on Multi-Throttle Engines

Link G4+ ECUs has a very powerful method of tuning engines with multi-throttle or long overlap cams. This tuning is based on both TPS and Manifold pressure. The Fuel Table Y axis is based on TPS, the Lambda/AFR Target Tables Y Axis is MAP or MGP.  The Target is used as a look up table for manifold pressure changes.  Based on the values in the Target Table, the ECU makes corrections for manifold changes in the fuel equation to adjust injector time.  The Fuel Table is tuned based on TPS and the ECU automatically looks after the changes in manifold pressure.  Another advantage of this method, is that the Target Lambda/AFR of the engine can be later changed without needing to retune the Fuel Table.The settings required are,

 

·	Equation Load Source: Load= MAP

·	Open Loop Lambda Table: ON

·	AFR/Lambda Target Table Y Axis: MAP or MGP

·	Fuel table Y axis: TP(Main)   So should I request my tuner to use the TPS instead of the usual MGP? Thanks.

[hspeck]

I forgot to state that I am running a single throttle, not multi throttle.

Thanks.

[ClintBHP]

BAP/MAP Xover might be best it can use the TPS corrected for barometric pressure up to NASP then swaps to MAP when , but the key is to try is and see if you find you can significantly increase throttle angle and not change cells in the map - i.e. real load changes but ecu load does not detect it creating lean/rich spots and also possibly wrong amounts of ignition.

That said your tuner should know all this !

[Adamw]

I would say with cams like that (they are not what I would consider high overlap) on a single throttle engine MAP will be nicely proportional to load.  You should be perfectly fine using the more typical load source = MAP & fuel table Y axis = MGP.  I highly doubt you will need to reference TP at all.

[hspeck]

Noted with thanks Adam.

I have since redone my maps and the car is running much better compared to the previous tune.

However, I was thinking the idling is still a little lumpy and could be better. The new tune is using ignition to control idling now.

I was looking at the tune and realized the minimum injector pulse width was set to 0.00ms. I am wondering if this might affect the idling?

Greatly appreciate if you can take a look at the map.

Tomei RB28 on Bosch EV14 1000cc injectors. I was told the injectors are too big...

Thanks.

joel04072017.pclr

[Ducie54]

I would set your idle base table first with idle ignition off. Then set idle ignition. You need a good ignition table start point first tho. High performance academy have a webinar on this subject that would explain it alot better.

If you increase your idle rpm it should help in making it smother also. 

A log file would be interesting to see. 

[hspeck]

I would set your idle base table first with idle ignition off. Then set idle ignition. You need a good ignition table start point first tho. High performance academy have a webinar on this subject that would explain it alot better.

If you increase your idle rpm it should help in making it smother also. 

A log file would be interesting to see. 

I was considering increasing the idle rpm too.

I will have to look into the idle ignition webinar. Thanks.

Attached a cold start log from this morning.

Log 2017-07-6 8;11;09 am.llg

Edited July 6, 2017 by hspeck

[b3tuning]

Had a look at your log and your calibration... was your wideband hooked up during the logging?  Showing extremely rich...  ~0.7 lambda!

Also, it looks like your idle ignition table and your main ignition table don't quite match around idle areas... can cause minor issues when transitioning from the ignition table to the idle ignition table and vice versa.

 

You could benefit from calibrating the injector short pulse adder table, and the setting the minimum injector pulse width... if available of course... 

 

Also, what type of idle solenoid are you using?  If it's the stock Nissan IACV, 15Hz is too low... with a higher frequency, the plunger in the solenoid will maintain an almost static position, either allowing more air or less based on base position.  This can greatly help achieve a stable idle with minimum interference from idle ignition tables.

And since you're having issues getting idle rpm's below 1000 rpm's, I'd revisit setting the bleed screw on the IACV and then redoing the base idle position tables.

I'd expect those cams to idle pretty solid at your target rpm's.  

 

[hspeck]

Had a look at your log and your calibration... was your wideband hooked up during the logging?  Showing extremely rich...  ~0.7 lambda!

Also, it looks like your idle ignition table and your main ignition table don't quite match around idle areas... can cause minor issues when transitioning from the ignition table to the idle ignition table and vice versa.

 

You could benefit from calibrating the injector short pulse adder table, and the setting the minimum injector pulse width... if available of course... 

 

Also, what type of idle solenoid are you using?  If it's the stock Nissan IACV, 15Hz is too low... with a higher frequency, the plunger in the solenoid will maintain an almost static position, either allowing more air or less based on base position.  This can greatly help achieve a stable idle with minimum interference from idle ignition tables.

And since you're having issues getting idle rpm's below 1000 rpm's, I'd revisit setting the bleed screw on the IACV and then redoing the base idle position tables.

I'd expect those cams to idle pretty solid at your target rpm's.  

 

Yes, I am using the AEM UEGO wideband. I did notice that the car was running rich too. I will need to do another logging when the car is warmed up sufficiently.

I am not sure about the idle ignition table, as I do not have knowledge about it. this is the first time I come across a tuner using the ignition to control idle.

As for the minimum injector pulse width, I have since changed it to -0.1408ms as per the Bosch EV14 specs. I did try to put in the pulse width adder information as provided, but the idling became worse.

I am running the stock IACV. If 15hz is too low, what should be a proper frequency? I read that the recommended value should be 200hz in the Link Help menu?

Thanks.

[kenecchi]

Would you happen to have purchased your injectors from NZEFI?  I ask because I have these injectors and I've had some trouble getting them to idle correctly.  They are supplied with short pulse width adder data that seems to indicate negative numbers, however I suspect that neither these numbers, nor the minimum effective pulse width should be negative.

[hspeck]

Would you happen to have purchased your injectors from NZEFI?  I ask because I have these injectors and I've had some trouble getting them to idle correctly.  They are supplied with short pulse width adder data that seems to indicate negative numbers, however I suspect that neither these numbers, nor the minimum effective pulse width should be negative.

Yes, I bought the 1000cc EV14 injectors from NZEFI.

I am not too sure about injectors specs though. Maybe the more knowledgeable here can advise?

Just to add.. the minimum pulse width is 0.1408ms... don't think it is negative ...

Edited July 8, 2017 by hspeck

[Adamw]

 They are supplied with short pulse width adder data that seems to indicate negative numbers, however I suspect that neither these numbers, nor the minimum effective pulse width should be negative.

It is normal for short pulse width adder numbers to be both positive and negative - this is because the injector flow rate at small PW's often deviates both above and below the nominal "slope".  The minimum pulse width should not be a negative number.   The minimum pulse width setting is not usually very important is it would be rare to ever command a PW that is too short under most normal running conditions.

 

I did try to put in the pulse width adder information as provided, but the idling became worse.

If the injector supplier has given you short pulsewidth adder data then you should use it.  You will of course have to re-tune the idle and low load areas of your fuel table if you change any injector data.

 

 

I am running the stock IACV. If 15hz is too low, what should be a proper frequency? I read that the recommended value should be 200hz in the Link Help menu?

Our GTR base map is set for 200Hz and it seems to work ok for most users at that.

 

 

 

[hspeck]

It is normal for short pulse width adder numbers to be both positive and negative - this is because the injector flow rate at small PW's often deviates both above and below the nominal "slope".  The minimum pulse width should not be a negative number.   The minimum pulse width setting is not usually very important is it would be rare to ever command a PW that is too short under most normal running conditions.

 

If the injector supplier has given you short pulsewidth adder data then you should use it.  You will of course have to re-tune the idle and low load areas of your fuel table if you change any injector data.

 

 

Our GTR base map is set for 200Hz and it seems to work ok for most users at that.

Thanks Adam. I have since changed the frequency to 200hz.

I will see if I can adjust the fuel table after changing the short pulse width adder.

@ Adam... I am using the AEM Wideband UEGO. 

http://www.aemelectronics.com/products/wideband-uego-air-fuel-controllers/digital-wideband-uego-afr-gauge/digital-wideband-uego-afr-gauge 

I tried to input the specs provided into Table 7 (uneven spaced non linear output), but there was not enough cells. So i selected the "AEM X-series UEGO" for the calibration. However, I realised thta the Lambda values in my logs is different from that displayed on my AEM gauge.

I tried to find the data in the pre-assigned "AEM X-series UEGO" but there is non available.

Please advise how I what I should do as I am unable to turn on the closed loop lambda because of this. I did not have this issue when I was using the Innovate LC-1 previously.

Thanks.

 

[Adamw]

 

I tried to input the specs provided into Table 7 (uneven spaced non linear output), but there was not enough cells. So i selected the "AEM X-series UEGO" for the calibration. However, I realised thta the Lambda values in my logs is different from that displayed on my AEM gauge.

I tried to find the data in the pre-assigned "AEM X-series UEGO" but there is non available.

The X-series uses a different calibration.  Yours looks linear to me according to the datasheet on the AEM website.  Use one of the linear cal tables, set 0V = 0.683Lam, 5V = 1.365Lam.

 

 

[hspeck]

Thank you Adam.

I thought it looked non-linear, my mistake. I should have used my calculator to check.

Very much appreciated!

Edited July 10, 2017 by hspeck

[hspeck]

And so I did the changes as advised, the Lambda 1 is now calibrated to Cal 4.

I did a brief run and realized that the AFR on the gauge and in the log is different. The AFR logged is showing that the car is running lean (previously running very rich when calibrated to AEM X series spec) compared to the Target AFR, whereas the reading on the gauge is very close to the target AFR, maybe difference by 0.2.

I am assuming that the tuner might have tuned the car based on the readings on the gauge.

The question now is, should I retune the car based on the logged AFR readings instead?

I am also assuming that I cannot turn on the closed loop lambda yet ......

Thanks.

[Steve]

Fudge the cal 4 calibration to make the ecu read the same as the gauge. What you are seeing is ground offset. Maybe the ecu and the gauge are grounded at different places? This is one reason why getting a CAN based lambda unit is such great idea.

[hspeck]

Fudge the cal 4 calibration to make the ecu read the same as the gauge. What you are seeing is ground offset. Maybe the ecu and the gauge are grounded at different places? This is one reason why getting a CAN based lambda unit is such great idea.

hmm... I think I should check the wiring first instead of meddling with the calibration on Cal 4... cos I wouldn't know which is correct in the first place ...

alternatively I am considering getting the AEM X series. apparently the reviews are quite good and it is not too costly too ...

I looked at the wires from the AEM gauge, basically they only need one single wire to the ECU, which in this case is my AN Volt 2 input. The ground is to the gauge's power ground ... so highly unlikely it is a grounding issue ...

Edited July 10, 2017 by hspeck

[Adamw]

 

I looked at the wires from the AEM gauge, basically they only need one single wire to the ECU, which in this case is my AN Volt 2 input. The ground is to the gauge's power ground ... so highly unlikely it is a grounding issue ...

If the gauge doesnt have a seperate analog ground and is grounded via a high power ground at some other location in the car then I would disagree with your statement and say the exact opposite.  It is highly likely a grounding issue...

You can try grounding it to the engine block which is often closer to sensor ground or you can try as Steve mentions above and "fudge the cal".  It is common practice and often needed with controllers that dont have a proper analog ground.  The problem you will often find though is you might get it working nice for a few minutes until a fan or headlights etc turn on then you suddenly find a different offset...

Edited July 10, 2017 by Adamw
typo

[hspeck]

I see. So I thought wrongly.

I was thinking I should try to measure the voltage from the gauge to the ECU to make sure the readings on the gauge is correct.

And maybe also to run the ground to the sensor ground on the XS Loom?

[Simon]

If there is only the one ground the XS loom one will not be able to support the current required. This is due to the ground being used for the O2 heater that will draw close to 10 amps when cold.

[hspeck]

If there is only the one ground the XS loom one will not be able to support the current required. This is due to the ground being used for the O2 heater that will draw close to 10 amps when cold.

I looked at my old maps with the Innovate LC1 and the AFR read fine ... so I am guessing it is probably due to the AEM UEGO that I have now. I will be replacing it with the AEM X-series. Waiting for it to arrive. Will update after I have it installed.

Thanks.