Nissan ECU Tuning

Performance_Addict · Joined: 29 Nov 2007 Posts: 10

Hi ya'll. I currently own a 1990 300ZX TT (US) 5 spd. I have 2.5 in SS exhaust no cats from turbos back, DOOLZ, 555cc, AMZ STAGE II TURBOS, UR pulley kit, Z1 Intercoolers, EBC running at 15 PSI (DD) and 18 PSI (Fun Time). I also have a tuned ECU. I have copied the code from my current ECU and have been making mods on the chip, but have some questions. I read the ECU tuning guide but there has been a few things I feel were left out.

When I expand the fuel and timing map to 8800RPM's, I am not sure how far to expand the timing and fuel values beyond 6400RPM. What I mean is this:

My current chip reads the following for Address 7D00-FF (FUEL) and 7800-FF (TIMING) respectively:

6400RPM FUEL MAP:
C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0
C0 C0 C0 C0 C0 BF BF BF 16 16 16 16 16 16 16 16
C0 C0 C0 BF BF BF BE BD BC 06 11 11 11 11 11 11
BC BC BD BD BD BD BC BB BA BA 05 11 11 11 11 11
BB BB BC BD BD BD BC BC BB BB 05 0A 13 13 13 13
B9 B9 BB BB BC BC BC BC BC BC BC 06 15 15 15 15
B8 B8 BC BC BC BC BE BE BD BC BC 0A 15 18 18 18
B9 B9 BB BD BD BD BE 00 01 05 0D 13 17 1B 1D 1D
BE BE BF BE BD BC BB 01 05 0A 10 17 1C 20 23 24
BB BB BC BC BB BA BA 03 08 0D 13 1A 1F 26 29 29
B9 B9 BA BA BA BA 02 07 0C 11 16 1E 24 29 2B 2D
BA BA BA BB BB 07 0C 11 17 1E 22 26 2A 2D 2F 30
0D 0D 0D 0D 0D 12 16 1A 1E 22 25 28 2B 2D 2F 30
0D 0D 0D 0D 12 18 1D 21 23 27 2A 2C 2D 2F 30 31
0D 0D 0D 0D 12 18 1D 21 25 28 2B 2C 2E 2F 30 31
0D 0D 0D 0D 12 18 1E 23 27 29 2C 2E 2F 30 31 32

Reading the ECU Tuning doc, I take the average of the four if it does not line up exactly from the old map to the expanded map. What do I do once I exceed 6400RPM? Do I keep going across with the same number left off from the previous 6400RPM map or slowly increase like the pattern on this line? Here is what I did for the expanded map:

C0 C0 BF 16 16 BC BC BC BC BC BC BC C0 C0 C0 C0
BE BF BE 06 11 14 14 16 3C 7C BC BC BC C0 C0 C0
BC BD BC BA 11 11 12 15 20 2F 35 40 55 70 85 A0
B9 BC BC BC 14 14 14 16 20 2F 35 40 55 70 85 A0
B8 BD BC 05 16 1A 1A 1B 20 2F 35 40 55 70 85 A0
B9 BD BC 05 15 20 20 22 2E 3A 46 4C 52 59 5E 60
BC BD BB 06 1A 22 26 28 2E 3A 46 4C 52 59 5E 60
B9 BA 04 07 1E 2D 2F 32 37 3F 3A 44 50 53 5D 60
75 75 0F 1D 25 34 35 37 34 31 2D 29 26 23 22 20
35 35 19 29 2B 32 35 37 34 31 2D 29 26 23 22 20
20 23 1C 2F 32 34 38 3B 36 31 2C 26 22 1E 1A 18
18 19 1D 2E 1F 21 3C 3C 34 2E 29 22 1E 1A 15 11
11 11 11 11 10 10 10 10 0F 0F 0E 0E 0E 0D 0D 0D
0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D
0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D
0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D 0D

Can someone give me clarification if this looks good and if not, how to correct my logic?

6400RPM TIMING MAP:
0F 19 16 14 12 10 0D 0C 09 08 07 07 07 07 07 07
14 29 25 22 20 1F 18 14 12 10 0D 0C 0B 0A 0A 0A
19 2A 28 28 28 26 25 20 1C 1B 1A 18 16 15 14 13
20 2C 2D 2D 2A 27 26 23 20 1D 1B 19 16 15 14 13
24 2D 2D 2D 2A 28 26 25 24 22 20 1A 16 15 14 13
24 2D 2D 2D 2A 28 26 25 24 22 20 1E 17 15 14 14
25 2D 2D 2D 2A 28 26 25 24 22 20 1E 17 15 14 14
26 2D 2D 2D 2A 28 26 25 24 22 20 1E 17 15 15 14
27 2D 2D 2D 2A 28 26 25 24 22 20 1E 18 15 15 15
28 2D 2D 2D 2C 2B 29 25 24 22 20 1E 19 15 16 14
29 2D 2D 2D 2D 2B 29 25 24 22 20 1E 1A 18 16 13
2A 2D 2D 2D 2D 2B 29 25 24 22 20 1E 1A 18 16 13
2B 2D 2D 2D 2D 2B 29 25 24 22 20 1E 1A 19 16 13
2E 2E 2E 2E 2D 2B 29 25 24 22 20 1E 1A 19 16 13
2E 2E 2E 2E 2D 2B 29 25 24 22 20 1E 1A 1A 16 13
2E 2E 2E 2E 2E 2B 29 25 24 22 20 1E 1A 19 16 13

Question: Do I continue across with 13 (last entry @ 6400RPM) or keep gradually increasing the number from 13 on up?

Here is what I did for the 8800RPM Expanded map:

0F 1D 15 10 09 09 08 07 07 07 07 07 07 07 07 07
20 27 23 18 13 11 0F 0E 0E 0E 0D 0C 0B 0A 08 07
26 2D 27 21 1A 16 14 13 13 12 11 10 10 09 08 08
28 2D 28 24 1E 16 14 13 13 12 11 10 10 09 08 09
29 2D 28 24 1F 17 15 14 13 13 12 12 11 11 09 0D
29 2D 28 24 1F 17 15 14 14 14 13 13 13 13 09 10
2A 2D 29 24 1F 18 15 15 15 14 14 13 13 13 11 13
2B 2D 2B 24 1F 19 16 16 16 15 16 15 15 16 13 16
2B 2D 2B 24 1F 1A 17 15 15 16 16 17 18 19 16 19
2B 2D 2B 24 1F 1A 18 15 14 13 14 15 18 1C 19 1A
2C 2D 2B 24 1F 1A 18 14 15 16 17 18 19 20 1C 1C
2C 2D 2C 27 24 20 20 13 15 16 19 1D 20 25 20 1E
2D 2D 2D 2B 29 29 29 25 17 16 19 1D 20 25 25 2E
2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E
2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E
2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E

Again, I think this may be too high for the timing advance on the expanded maps? Can someone clarify this for me?

I am using the Excel chart to place the new values, but seem to lose reason when hitting the end of the original 6400RPM fuel and timing maps. Do I keep increasing fuel and the timing, slowly increase, or continue with the last number used from the previous cell? What am I missing? : )

Sorry for the long thread...

The_S_Man · Joined: 21 Apr 2006 Posts: 19 Location: Arizona

I have a couple questions for you about this?

First - Are you changing your rev limiter also? I don't see a reason to expand the map to 8.8K rpms if you are not increasing the rev limit to above 9K. And whether or not your engine can handle a 9K+ rev limit is another discussion that you probably need to be considering.

Second - My opinion is that there is no reason to expand the maps if you are not tuning your car with a wideband O2 sensor. My personal belief is that you expand the fuel map to allow for more granularity of fuel metering at the higher RPM range (and the same with the timing). If you are not tuning with a Wideband O2 sensor, then you have very little to no idea what values need to be into the "expanded" part of the map.... therefore you are probably better off leaving the fuel map as it was.

Hope this helps...
-Jamie
_________________
Jamie
the_s_man@juno.com
The_S_Man (Phoenix) on TT.NET
1990 TTZ with GT28R
1990 N/A

Performance_Addict · Joined: 29 Nov 2007 Posts: 10

Thanks much. That is the answer I am looking for. I am running the stock O2 sensors. I have raised the limiter to 7500. So much to learn. Thanks again. I really appreciate your response...

Performance_Addict · Joined: 29 Nov 2007 Posts: 10

I created an extended fuel and timing map for 8000RPM's. The HEX equivalent divided evenly. Here is my chart in case anyone wants to try it out. It is winter here so I cannot test it until this Spring...

Expanded Fuel Map

C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0 C0
C0 C0 BF BE 2B 13 13 13 14 15 15 15 15 16 16 16
BE BE BE BC 35 11 11 11 12 12 13 13 12 12 11 11
BB BC BD BC 60 0E 13 13 12 12 12 13 13 13 12 12
B8 BB BC BD BC 0F 16 18 17 17 16 16 15 14 14 13
B9 BC BC 5F 62 12 17 1A 1A 1A 19 18 18 19 19 19
BB BD BD 0 0B 17 1B 20 20 20 20 20 1F 1F 1E 1E
BB BC BB 3 10 1C 22 29 28 26 25 23 22 21 20 20
B9 BA BD 0C 19 24 29 2D 2C 2B 2A 29 29 28 27 26
63 63 38 15 21 28 2B 2F 2D 2C 2B 2B 2A 29 29 29
0D 0D 12 1D 26 2B 2D 2F 2F 2D 2C 2B 2B 2C 2D 2D
0D 0D 15 21 29 2D 2E 30 30 30 30 30 30 30 30 30
0D 0D 15 23 2A 2E 2F 31 31 31 31 31 32 32 32 32
0C 0D 0F 17 21 28 2C 2E 2F 30 30 31 31 32 33 33
0C 0C 0D 11 18 20 26 2A 2C 2E 2F 30 31 32 33 33
0C 0C 0C 0E 12 18 1F 25 27 28 2A 2C 2E 30 32 34

Expanded Timing Map

19 1F 1A 12 0C 9 9 9 9 8 8 8 7 7 7 7
20 28 24 1E 16 12 11 0F 0F 0E 0D 0C 0B 0B 0B 0B
23 2A 29 25 1D 19 17 15 13 13 12 12 11 11 10 0F
28 2D 2B 26 23 1D 18 15 13 13 13 12 12 12 11 11
28 2D 2C 26 23 1F 1A 15 14 14 13 13 12 12 11 11
29 2D 2C 26 23 1F 1A 15 14 14 13 13 12 12 11 12
29 2D 2C 26 23 1F 1A 15 15 15 14 14 13 13 12 12
2A 2D 2D 29 23 1F 1B 15 15 15 15 14 14 13 13 13
2B 2D 2D 29 23 1F 1C 18 14 15 14 14 14 13 13 13
2B 2D 2D 29 23 1F 1C 18 15 15 15 14 14 14 13 13
2D 2D 2D 29 23 1F 1C 19 15 15 15 14 14 14 13 13
2E 2E 2D 29 23 1F 1C 1A 15 14 13 13 13 13 13 13
2E 2E 2E 2C 28 23 1F 19 15 15 15 15 15 14 13 13
2F 2E 2E 2D 2B 27 23 1E 19 18 17 16 15 14 13 13
2F 2F 2F 2E 2C 2A 26 22 1D 1E 1F 10 11 12 13 13
2F 2F 2F 2E 2D 2B 29 25 21 1F 1D 1B 19 17 15 13

You have to change your TP Scale, too. Don't forget. I will post back unless someone makes any changes before I do. Happy tuning...

RomChip200 · Joined: 27 Nov 2003 Posts: 196 Location: France

Expanding a map to finally have the same content in 2 columns is meaningless as your 15th and 16th columns in timing map.

For fuel map, TP (according to boost) will go higher and higher, except if you have put some limit in TTPMAX, this will be the base value used to inject.
In timing map, TP can go very high, but once you are above the value corresponding to the 16th column, the ECU will apply the timing found in the 16th column (the last one ...).
_________________
200SX CA18DET S13 '92.
300ZX TT '91.