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Hi I've added the following mods to my car and am wondering if anyone has a bin file for a setup similar to mine that I could use as comparison to help guide me in the right direction?

poncam type b
tomei 7655 turbos
1000cc injectors
nismo afms

cheers

Probably not but the Nismo AFMs use the Z32 MAF setting in Nistune (make sure to use the halve tickbox when resizing MAF)

Also adjust for the 1000cc injectors and find out the latency (start around 900uS if unsure) then use an AFR meter and adjust injection mutliplier to get the car running right again

I have a question about the half sizes option, the curves don't make sense after the sizes are halved. The z32 curve ends up needing more voltage for the same airflow quantifier, where as the curve should be less voltage for the same airflow. If I don't half the values then the curve makes sense, although it has values all the way to 65575 at 5.1v but the calibration graph that comes with a nismo maf shows they are only meant to read up to about 4.1v which in the curve is somwhere around a 32xxx value. And to clarify I am replacing the 2 factory gtr afm with 2 nismo afm

Can you post the nismo calibration graph, please. I had alot of problems with the last car i tuned with nismo afm's, but it was with a Apexi Power FC and huge modifikations, like big singel throttle body, big turbos etc. The Power Fc isn't a very good ECU for high modified cars, especially if you change the multithrottle to a big singel. It changes to much, and there are to less tables to compensate that.
I have to tune a GT-R32 this week also with Nismo AFM's, bigger turbos etc. I'm very curios how well it will work with Nistune, but i think well.

mikeyrhd wrote:I have a question about the half sizes option, the curves don't make sense after the sizes are halved. The z32 curve ends up needing more voltage for the same airflow quantifier, where as the curve should be less voltage for the same airflow. If I don't half the values then the curve makes sense, although it has values all the way to 65575 at 5.1v but the calibration graph that comes with a nismo maf shows they are only meant to read up to about 4.1v which in the curve is somwhere around a 32xxx value. And to clarify I am replacing the 2 factory gtr afm with 2 nismo afm

this is the curve supplied by nissan, I don't have a nistune vq map version



when you do a change maf in nistune and select half values you get a graph like this, where the red line is the z32 maf(no nismo vq available in nistune) and pink is the stock gtr maf. I'm not sure how the airflow/voltage translates into the vq maps in nistune but to me this does not look right? I'm assuming that in the nistune vq map that the y axis a higher value relates to higher airflow, so like I mentioned the z32 maf should be reporting a lower voltage for the same airflow as the gtr maf.



If you don't half the values you get the below graph which to me looks correct(red is z32, pink gtr)


also note worthy is that the nissan graph only goes upto 4.3, the flow at the full 5v would be huge

Matt wrote:Probably not but the Nismo AFMs use the Z32 MAF setting in Nistune (make sure to use the halve tickbox when resizing MAF)

Also adjust for the 1000cc injectors and find out the latency (start around 900uS if unsure) then use an AFR meter and adjust injection mutliplier to get the car running right again

Matt is the halve tickbox not for the reason that you change from a original singel MAF setup to a double MAF setting, isn't it? GT-R has stock double MAF, so i think the right way is without halve the MAF values.

what kind of mods does the car you are about to tune have?

mikeyrhd wrote:what kind of mods does the car you are about to tune have?

Main specs are
- Nismo AFM's (used ones, i hope they work right )
- Garette GT2860- 7
- Big FMIC
- Open pod filters
- Better flowing ex-manifolds 3.5" Turboback Exhaust
- Not sure about the Fuel Setup, i thought Sard 650cc injectors, but i will see it on Wednesday.
- A few other modifications to support 500BHP (on the engine)

Why do you ask?

curious if it is similar to mine, I get the concepts of tuning just don't have the experience, I want to get a professional dyno tune done next year but it is far from me and I want to try and make my car as drivable as I can myself

The information about the Nismo MAF using Z32 scales was based from discussion with a tuner that PowerFC uses the Z32 VQ map selection for Nismo MAF in the selections.

From the curve posted above (yellow diagram) you can see that Nismo MAF is very similar but the middle of the curve needs to be richer than the Z32 curve at the moment. That graph provided does not have the full 5v range making it difficult to rescale this against 0-63 cells

So we dont have a proper VQ map for it yet it appears. Where would one source this from (apart from Nismo?)

....

Okay the VQ maps scaling....

Look at the values for the BNR32 VQ map and you will see its 0 ... 32767. This is half the total range of the VQ map. BNR32 has two AFMs, so takes the measured value twice to turn it into a final number. So the effective final VQ map value is doubled inside the ECU (due to two AFMs)

Have a look at a VQ map for anything other MAF and it will be 0 ... 65535. This is the full range of the VQ map. When moving to the BNR32 with 2 x AFMs you need to cut this in halve. Hence you have to use the halve tickbox. This feature was added for a tuner who was upgrading MAFs on the BNR32 to Z32 and required this option

The double tickbox is for using a BNR32 VQ map on another ECU (not common but we provide this feature anyway on request)

As Z32 is similar to Nismo MAFs VQ map then you still need to halve as per first Nistune graph and then tweak the middle of the VQ map if you want it matching that diagram

but looking at the end result of halving the values wouldn't you agree that it looks wrong? or is airflow not directly related to the 0-65k value? It doesn't make sense that the z32 maf would read a higher voltage for the same airflow as the gtr maf

also it shouldn't matter if the vq map goes abouve 32768 because the airflow at a value of 32768 on the unhalved z32 maf would represent a horsepower rating somewhere in the neighbourhood of 550-600hp I think

but looking at the end result of halving the values wouldn't you agree that it looks wrong?

No I dont agree it looks wrong. The Z32 VQ map needs to halved to get the 0...32768 range

All single MAFs ECUs regardless of type will have a VQ map scaling between 0..65535 regardless of their load reading capabilities.

Don't confuse volt to TP calibration vs airflow the MAF can read. That is calibrated by adjusting K constant for the amount of load read

or is airflow not directly related to the 0-65k value?

Well... Maximum airflow that MAF can read

It doesn't make sense that the z32 maf would read a higher voltage for the same airflow as the gtr maf

Well it would actually read a lower voltage than the GTR MAF on the same load. I never said it could read a higher voltage

also it shouldn't matter if the vq map goes above 32768 because the airflow at a value of 32768 on the unhalved z32 maf

Yes it will matter. If you have a Z32 MAF x 2 plugged into the GTR, then using an unhalved VQ map at 5.12 volts on each sensor will grab the last value of about 65535 (MAF1 vq) + 65535 (MAF2 vq) and overload the maximum number allowed in the ECU

would represent a horsepower rating somewhere in the neighbourhood of 550-600hp I think

This is where K constant is adjusted for the load reading, not the calibration of 0-65535 translation for that maf vs 0-5V range

Anyway despite this - using halve values for other VQ maps is a tried and tested tuning thing done by tuners on GTRs. I think you will just need to trust us on this one

ya I haven't even tried it yet myself but I thought I should ask since it was bothering me, and since this is a polynomial equation if you take the output and divide by 2 you are radically altering the curve

But since the VQ map is added twice internally then the curve is actually doubled

If i interprete the voltage vs TP curve from the Nismo AFM right and you tweak the Z32 curve to a bit to match the nismo afms. you will end with the same curve as the orginal BNR32 AFM-curve, isn't it?

I could make sense, that nismo has choised the same curve, that you have only adjust the K-Value?
What do you think about, can it be? Or would i be mistake in suggestion? However i will try it out in the next days...