Bryan,

On the ECU Tables from ECUFlash I only see:

Boost Enhancement (Anti-Lag) Start RPM: 2500
Boost Enhancement (Anti-lag) Stop RPM: 4531

Is this what you are talking about? This is an 04 EVO8.

 

Sorry, 22 pSI until 5500 RPM is never stock boost

 

He's not logging psi, he's logging Load, which is approx. kPa.

Load - 100 to get the amount of boost, which is 220kPa - 100 = 120kPa = 1.2 bar = 18psi

 

the quick fix is to make both 2500.

 

Not the antilag maps.

There is a thread in this forum if you search showing how to change the lean-spool settings.

 

Yea!. I saw that thread but it says it’s a How to for Evo IX. I was not sure if it would be the same for an VIII.

 

Lean Spool Disable
Why?
When in open loop operation, the factory ECU artificially leans the fuel mixture by about 1 full ratio point which can cause difficulty in tuning for proper AFR. Disabling "Lean Spool" will also allow for your map AFR numbers to more closely align with your actual measured AFR.

How?
OPTION 1
1.) Open ECUFlash v1.3 and a version 15 ROM image. Scroll down and expand the Misc section.
2.) Right-click somewhere within the Misc section and select "New Map."
3.) Click the evo9base tab at the top.
4.) Enter the map Name "LeanSpoolEnable"
5.) Select the Type as "1D"
6.) Enter the Address of "1281"
7.) Select the Scaling entry "unit8"
The form should look like this:

8.) Click Apply then OK

Now do the same thing to make a "LeanSpoolDisable" map that looks like this:


9.) Click the box next to LeanSpoolEnable and change the value to "48" (which translates to 1500rpm) and change LeanSpoolDisable to "48" as well.
10.) Save the ROM file. Flash the ROM onto your IX and begin tuning your AFR with a much more logical and predictable foundation.

OPTION 2
1.) Go to "boost enhancement (anti-lag) Stop RPM"

2.) Right click on it and select "edit map"

3.) Change the address to "1284", click apply, then OK

4.) Make both the "boost enhancement (anti-lag) Stop RPM" and the "boost enhancement (anti-lag) Start RPM"
the same. For example, set both to 1500rpm.
5.) Save the ROM file. Flash the ROM onto your IX and begin tuning your AFR with a much more logical and predictable foundation.
--------------------------------------------------

Here are the lean spool tables for the Evo 8 94170008:

------------
<table name="Lean Spool Start RPM" category="Misc" address="1680" type="1D" level="1" scaling="RPMStatLimit"/>

<table name="Lean Spool Stop RPM" category="Misc" address="1684" type="1D" level="1" scaling="RPMStatLimit"/>

<table name="Lean Spool Load Threshold" category="Misc" address="39A2" type="2D" level="1" scaling="Load8">
<table name="input value" address="63DA" type="X Axis" elements="14" scaling="RPM"/>
</table>

<table name="Lean Spool Trailing Time (Rich Side)" category="Misc" address="397A" type="2D" level="1" scaling="uint8">
<table name="input value" address="63DA" type="X Axis" elements="14" scaling="RPM"/>
</table>

<table name="Lean Spool Trailing Time (Lean Side)" category="Misc" address="398E" type="2D" level="1" scaling="uint8">
<table name="input value" address="63DA" type="X Axis" elements="14" scaling="RPM"/>
</table>

<table name="Min Temp for Lean Spool" category="Misc" address="167E" type="1D" level="1" scaling="Temp"/>

<table name="Lean Spool Enable Load Hysteresis" category="Misc" address="167C" type="1D" level="1" scaling="Load16"/>

<table name="Lean Spool AFR Mapping" category="Misc" address="39B6" type="2D" level="1" scaling="AFR">
<table name="base AFR" address="6400" type="X Axis" elements="7" scaling="AFR16"/>
</table>

<table name="Lean Spool AFR below Enable" category="Misc" address="1682" type="1D" level="1" scaling="AFR16"/>

<table name="Lean Spool Clip Value" category="Misc" address="1686" type="1D" level="1" scaling="AFR16"/>
------------

You'll also need to add this line to the "evo7base.xml" file:

 

If I disable lean spool then I will have to redo the whole fuel maps from 2500 to 7000 right? That includes all the cells and possibly the low octane maps also. Is this correct?

Would it be a better idea to enable lean spool to 7900 (like razorlab states) and then tune the car even if the lean spool is enable from 2500 past redline? It is unlikely that I would need to change the cells lower than 2500 in a tune right?

Have any one found any relationship from the lean spool enable change point (about 2500 RPM) and the low RPM knocks seen on some EVOs? I am seeing some low knocks starting on the 2600 RPM area.

 

Slightly off topic but,

I have an 03 evo and when I had it tuned with the stock fuel pump the tuner said I was at around 85-90% IDC. I set my boost back down to 18/19 PSI. Now I just put in a walbro so I can up the boost again and it's my understanding that currently my IDC's are still unsafe without a retune correct? And that I need to retune it to increase boost?

I'm having a hard time grasping the logic behind it all. The fuel pump has made my car richer, so I have more leeway to take out fuel and thus lower my IDC? Or is it because of what l2r99gst said :
"Yes, that is because the pump can't maintain the 1:1 fuel pressure with boost. The VIII pumps drop have a relief valve that open and flow drops dramatically."

What I don't understand is that everyone says a fuel pump allows more boost, but if I lean it out some more and lower the IDC, and then turn up the boost some more, won't I require more fuel again and subsquently reach unsafe IDCs again? Or is there more involved than just AFRs as what l2r99gst explained?

 

The stock VIII fuel pump cannot supply sufficient flow at boost levels above stock. Basically, 90% IDC on a stock pump at elevated boost level is not actually 90% of what the injectors can flow... the fuel pressure behind them is weakening. You run leaner.

If you add a Walbro, the fuel pressure comes back up to where it should be, and the 90% IDC is a true 90% IDC. You run richer.

 

I did one third 3rd gear pull as a test log and it maxed out at 95% IDC(just started working on tuning myself). I was wondering how much, in your guys experience, that you were able to lower IDCs with the install of a fuel pump and leaning out the car? I only reached a peak of 225 Load and assuming i have no boost leaks(I did a leak test about 3 months ago), then I am actually doing around 18-19 psi right?.

I know it would be better to just first tune it out and then see, but i figured i would ask anyway. Is it time for bigger injectors? When I lean it out and turn up the boost some more is it possible to have safe IDCs?

My mods include
TME turbine with 9.8hotside,
AMS Licp, IC, dp, hiflow cat, catback,
Ported stock manifold + ebay 02 housing
Walbro 255

if that helps. I thought there were pretty mild and injectors were at least after cams or something.

 

Increasing the size of your injectors on a stock VIII fuel pump will do nothing for you. It's the drop of the fuel pressure that's maxing out your IDC, not the injectors themselves.

 

Sorry, forgot to say my mods now include a walbro 255.

 

Well if you're maxing your injectors now too, then yes it is the next step