TYPE 4 Board 3J40F Tuning Advice SR20DE+T

[noynek]

Good day all,

My Set up is an Sr20DE+T , 370CC inj ,T25 Turbo , W11 Sr20DET MAF.
I am Using the P11 SR20DE FP ECU 3J40F

I have successfully Resized Injectors , Converted maf and Ajusted TP min Valuse Etc. to Get good start up and Close to Zero FT's at Idle .
I've also rescaled the Load Axis to mirror that of the DET ECU's Fan control and all those other things I've covered and understand.

I am at the point where I'm a bit Confused on how to Tune for fuel on a boosted setup with the VE table and Fuel Correction MAP.

I've tried to "turn off" VE Map accessing by increasing valuse to 255 in the Alpha N Table. But I still feel as if the ECU is "fighting" changes.

Also I'm using as a "Mirror tune" A stock W10 MAP running in a separate instrance if Nistune and usung that to comparre fuel Map Values.

Issuse - It sems to me that all RAW values of the P11 Fuel map Starts at 128 whereas in the W10 Map I can enter a value less than 128. I cant seem to rationalise this in my mind

How can I use the information ( if at all possible ) in the W10 Fuel Table to help me With tuning my setup? Is it even possible. Or is this a case of tuning from "Scratch" the fuel maps on the P11 ECU?

What should be my approach going forward with respect to the fuel values?
Which table should I modify first?
Shold I hold onne constant and then tweak with the second ( VE ) table?
Is this just an iterative process?

Most of the persons in my neck of the woods have experience with tuning the Non VE boards for turbo application.

Any pointers in the right direction would be greatly appreciated

Anyone who has had good success with tuning these VE type boards for turbo application please feel free to offer some advice. I'd greatly appreciate it

Cheers
Kenyon

[Matt]

Get good start up and Close to Zero FT's at Idle

You need to setup your base mixtures for cruise (2000rpm light load).... not idle

I've also rescaled the Load Axis to mirror that of the DET ECU's Fan control and all those other things I've covered and understand.

Normally I would leave the load scaling alone (as factory) rather than copy the one from the DET. Load scaling is specific to each ECU rather than each application (in this case being turbo bolt on)

I am at the point where I'm a bit Confused on how to Tune for fuel on a boosted setup with the VE table and Fuel Correction MAP.

VE map is effectively on Nissans a throttle enrichment map. It is indexed by TPS and RPM to adjust mixtures based throttle position. Normally it should not need adjustment

I've tried to "turn off" VE Map accessing by increasing valuse to 255 in the Alpha N Table. But I still feel as if the ECU is "fighting" changes.

This will cause problems. You should leave it alone, and just adjust the fuel map to achieve the mixtures you require as displayed on your wideband

Also I'm using as a "Mirror tune" A stock W10 MAP running in a separate instrance if Nistune and usung that to comparre fuel Map Values.

The P11 ECU has a map starting at (raw value) of 128, where the W10 map start from 0. You will need to put the P11 map in 'filtered' and then copy a turbo (say S13 SR20DET) fuel map into that if you want a starting point. P10 is non turbo so no point using that

Issuse - It sems to me that all RAW values of the P11 Fuel map Starts at 128 whereas in the W10 Map I can enter a value less than 128. I cant seem to rationalise this in my mind

Nissan changed the representation of the fuel map internally (RAW mode) so work under 'filtered' instead.

How can I use the information ( if at all possible ) in the W10 Fuel Table to help me With tuning my setup? Is it even possible. Or is this a case of tuning from "Scratch" the fuel maps on the P11 ECU?

Open two copies of Nistune, and copy maps by selecting then and paste in 'filtered' view

What should be my approach going forward with respect to the fuel values?

After copying in the fuel tables, then adjust the values to get AFRs that you need. Make sure your load cursor goes all way to the last column and adjust K if too far/not far enough (correct load indexing)

Which table should I modify first?

Refer our tuning guide. Normally I would
1. Increase limits (speed, RPM, load [TP])
2. Adjust MAF, injectors
3. Adjust K constant until load cursor operates within current scales
4. Adjust TIM so fueling is stoich at cruise, with near 0% STFT/LTFT
5. Adjust latency so idle is happy
6. Pull back timing on boost so it is safe for loading up
7. Adjust fueling maps to achieve around 11.5:1 AFR on boost
8. Tweak timing using peak torque method and headphones for monitoring detonation (particularly SR20DE+T setup)

Shold I hold onne constant and then tweak with the second ( VE ) table?

Leave this table alone unless you have acceleration issues after completing the tune

[noynek]

Thank you Thank you Thank you.