Tested the 8859 3D SD rom and works perfect everything is fine, only issue between 1800-2600rpm can't cruesing with fix throttle because feeling the jitter. In lower gear 3-4 worse . Is there any jitter fix for 8859 ?

 

Did you notice the same jitter in 8858 rom when you tested that?

For 8859 try these (IIRC #2 was the one that offers best result):

<table name="SD Stutter Fix Option #1 (Set Over/Under Flag for MAF Signal Averaging Val)" category="Speed Density Programming" address="122c" type="2D" level="2" scaling="uint16">
<table type="Static Y Axis" elements="1">
<data>Stock = 205 For Fix Option #1, Set = 255</data>
</table>
</table>

<table name="SD Stutter Fix Option #2 (Set Scaling Factor for Transition Load)" category="Speed Density Programming" address="1230" type="2D" level="2" scaling="uint16">
<table type="Static Y Axis" elements="1">
<data>Stock = 112 For Fix Option #2, Set = 0</data>
</table>
</table>

<table name="SD Stutter Fix Option #3 (BT -> NOP for DeltaMasterLoadPos/Neg Threshold)" category="Speed Density Programming" address="2A972" type="2D" level="2" scaling="Hex16">
<table type="Static Y Axis" elements="1">
<data>Stock = 0x8909 For Fix Option #3, Set = 0x0009</data>
</table>
</table>

 

I thought that the evo ix were not reported to have any jitter issues? AFAIK..?

 

I have it with 8859rom on USDM Ecu and 1450cc.. cant go fix throttle between 1800a-2600rpm sometimes ! Other issue after shifting rpm went to 2000-2500 and the car is stumbling ! Anyway everything works perfect, fuel trims are right the car is strong !

 

Is there a 8858. Sd2.0 rom available?

 

Yes, I have ported code to 8858. I excluded baro code which does not work correctly anyway and did not have time and/or real need to rewrite it.

 

I been using 8859 for a few months now, no jitter and with a wide range of driving environments.

using:
Omni 4 Bar
GM IAT sensor
Spooling-up harness
PE880 injectors
Custom Twin pump

If there is a table you need me to look up, let me know, But its mostly unmolested from what roadspike had.

 

Nevermind its all working right now.

 

with jitter 1 and 3 turn on and more fuel in the 2000-2500rpm running better ! now only issue with faster shifting and higher load in the that area and sometimes steady throttle at 2000-2500 rpm in 1-2-3 gear . But at all perfect and driveable !

 

This is how I have accomplished my 3dsd tune. My fuel map reads my desired AFR, while I move the VE to the number that allows me to reach that desired VE. There is a little setup required, but this is easier than MAF tuning for me.

 

How is everyone getting on with this rom these days?

Im getting ready to start autox'ing again and not quite happy with my part throttle/off boost conditions in my 2d sd 9417 rom. My last try with this was the 9653 variant and never could elliminate the jitter. So I figured Id give the 9417 3d variant a try. Is it still the one that has reported the least amount of "jitter"? What fixes are being used?

 

Today was the 1st commute on the 9417 3dve rom. And to my surprise, I did not notice a single bit of jitter. I remember it being quite noticable in the 9653 3dve rom. Im using the original fix #2. Still have a lot of VE tuning to do, but so far so good.

 

I saw no studder in the 9417 rom, but tons in 9653. Still went to the old SD rom though, 3d was too much change all at once for me. I think I used the 2nd fix as well, the maf cutoff one, and it did fine for me.

 

Does anyone else use the fuel map as a point to adjust the VE to? Or am I the only one there? What other method is there?

 

Yeah, I set map-kpa and kpa-load to 1:1. Then tune the 3d rpm ve table until my wideband matches the fuel map.

With 2D I used the rpm VE and MAF Comp to do the same. But was having part throttle rich conditions that were hard to tune out with two 2d tables as opposed to one 3d table.

Oh..and I pretty much tried to get the stutter on the way home and got none. High gear, low rpm, slowly accel, still nothing that I could feel.