Engine is 401 stroked SBC with a P600b on it.with a birdcage iat in a super ram plenum. I had been using the table iat/cts blend filter heavily biased to cts. Today I tried going back to the original table that is biased to iat temps. My iat's on a 90F day with intercooler run 120s, however on a hot day they go up and after sitting and then restart they are 150s until I can get some speed/air moving. Of course under boost they go up also. Logging and attempting VE learns I'm finding that the difference iat 120f at the same KPA and RPM compared to iat 150f will change the blm from 128 to 140-the higher the iat the leaner it goes.
In 8D there are two tables-inverse mat term lookup delta multiplier vs airflow and mat compensation counts vs mat. I remember in the past I had been able to use those to get consistency between mat temp and blms.
Is there something in the ebl p4 to accomplish that? Am I having a brain fart and not seeing it?

Did some more testing-ve learns with iat 120f and 128 blms obtained. Then once it's heat soaked (iat 160F+) I switched the iat/cts blend filter between biased to iat and all 100% cts and no difference seen it went very lean=blms 138 to 140s. There has to be a way to "calibrate" the iat temps to get consistent afr/blms.

 

I am by no means an ebl person but I thought he only added functionality and blended the best logic to form his final product.

in other words if it’s in $8d it should be in the ebl, worst case named something different and/or with slightly altered logic.

 

If anyone could pick out the "mat compensation counts vs mat" table in the ebl p4 I think that would be the solution. I tried opening the P4 bin with 8d hoping that table would match up but no luck.
Buccaneer-is that a possibility?!

 

Iirc bob had told me it was code $58 or $59 based

 

Hmm, tried opening it with the 58 xdf, but there is nothing in there that's near to being mat compensation counts vs mat.
I may just swap back to a 730 ecm and try out the S_AUJP V7.
I was thinking if I got the iat out in front of the throttle body, but after a hot restart the air in the plenum is still hotter so it would still go lean.

 

I'm runing 8D, SAUJP_v7.

I have a conical air filter located under where the battery tray used to be, in front of the passenger side front tire.

I then stuck a 4th gen LT1 IAT sensor into the snout of the filter. A true IAT sensor... not the CTS/MAT sensor that GM stuck in the metal TPI plenum.

With a non-metallic air tube, I figured there's very little heating from the filter to the manifold, so the ECM reads that as the manifold air temp. It may run a little richer, but I avoid the problem of heatsinking the IAT sensor by having it in the engine compartment.

I also disabled the INV MAT table in and only tune off the MAT Compensation Counts table.

Then with the Miniram so similar to the 4th gen LT1, and the 8D code so similar to the 90-92 LT1 DA2/DA3 speed density systems, I used the MAT Comp table from DA2/DA3 and then tuned my VE's and AE around that.

Seems to work really well.... although mine is naturally aspirated.

 

Sounds like a good plan. What pin is the input for a wideband?

 

The IAT correction table is hardcoded in the ROM, this was always a limitation of the P4 architecture, it can't model rising charge temperature under boost and the EBL was no exception. This is why you're seeing no real changes when you adjust certain parameters using the MAT/IAT. Bob did use a calculation for the EBL P4, but it cannot be altered in the XDF. We don't really have a charge-temp model, you tune the VE at a reference IAT, you would then use the IAT/MAT compensation to flatten the BLM vs IAT outside of those specific ranged areas. Outside of this you would do what the Buick guys do, larger intercooler's, methanol injection, e85, or newer firmware...

- Rob

 

I believe F14 or A3. Its selectable in the flags in the TP XDF file.

 

Thank you! Also do you know if VEmaster 2.11 8D works on sajup v7?

 

That I'm not sure... I'm not familiar with VEMaster.

 

ve master takes your ve tables and by blms adjusts it to whatever blm you want it to.Like learn ve.

 

Ah... ok. lol...

I ended up making my own tool to that. It uses the Tunerpro History Tables as input.

 

I could fix that.

 

There are in fact a few ways around this, but this depends on the new owners intent with the EBL’s coded logic. For instance, instead of relying on the ECM's internal air density model, the ECM could monitor the actual wideband AFR in real-time. A sudden Lean condition in the MAT logic under boost, you can trigger the Proportional Gain logic to see the Lean error and automatically add fuel to hit the targeted air fuel ratio. I believe Eric Marshall uses this exact strategy to correct the hardcoded logic in the P4’s architecture…

- Rob