EGR Delete OBD1 1994 Corvette

[lesman]

I removed the EGR and AIR Pump when I put headers on the LT1 corvette. I followed a B body EGR Delete that was generated by EEHack online tool. Just compared the bins from a normal LT1 Y body and tried to get everything related to the EGR / AIR pump system. There were too many other related items to check all the differences so I might have missed a couple or so.
When I ran my logs I noticed I was getting an EGR duty cycle on the graph. After seeing this, I zeroed out the EGR Spark Advance Correction ( I missed that one and added it). The spark advance shouldn't happen any more.
Is there something to stop the duty cycle of the EGR? It shouldn't be calling it all. I put the maximum RPM to 0 and the minimum RPM to 6500 as in the tool generated bin.

[LeMarky Dissod]

Is there something to stop the duty cycle of the EGR? It shouldn't be calling it all.
I put the maximum RPM to 0 and the minimum RPM to 6500 as in the tool generated bin.EGR Min MAP > 103KPa
EGR Enable Min RpM 6375RpM
EGR Enable Max RpM 6350RpM
EGR Enable Coolant Temps (both) > 116C

No need to zero the EGR table with constants set as above.

[lesman]

EGR Min MAP > 103KPa
EGR Enable Min RpM 6375RpM
EGR Enable Max RpM 6350RpM
EGR Enable Coolant Temps (both) > 116C

No need to zero the EGR table with constants set as above.

I found the first 3 settings but not the 4th (EGR Enable Coolant Temps). I looked through all the tables and scalars. Using TunerPro with EEX.xdf.
I found the AIR Enable - Min Coolant Temp and I added 116 for that.

[In-Tech]

Yes, some of the early stuff was in weird areas, IAT enable egr, watch for that. Either way, it's a one way, both have to pass enable check to qualify. :)

[NomakeWan]

I found the first 3 settings but not the 4th (EGR Enable Coolant Temps). I looked through all the tables and scalars. Using TunerPro with EEX.xdf.
I found the AIR Enable - Min Coolant Temp and I added 116 for that.
The two EGR Enable Coolant Temp addresses are 2617 and 2618. You can find them using EEXTRA v0[1].001[MOD_V0005_03_02]V6_3.xdf, which can be found here: http://www.gearhead-efi.com/Fuel-Injection/showthread.php?5029-The-ultimate-LT1-EE-patch-thread&p=92678&viewfull=1#post92678

[lesman]

I tried downloading the file but its doesn't load as a valid ZIP file but a RAR file with a ZIP extension add on. When I remove the zip extension and decompress it, it is EEHack executable only. I do not see any XDF file. Where can I find the correct file noted in the forum?
If it is not available any more, how do I manually add the parameters in Tuner Pro?
Is there a way I can create a new scalar in the program and add them that way? and if so, what would that process be?

Edit:
I found the XDF file that has a lot of the information you referenced. Also some other EGR settings that could be changed. I am still getting a duty cycle graph on the logger but I did not find the XDF till after I made my trip. It was not the one you referenced on page 10 but the XDF on page 6, version 5.
I will change the settings and give it another shot.

[NomakeWan]

The XDF file is attached directly to the post I linked. It's the XDF that you'd want to edit the BIN. There's no reason to grab that modified EEHack executable if you aren't planning on using the custom patches. Just download the attached XDF by itself.

[lesman]

The EGR duty cycle has stopped logging. I changed the settings from the list above and it worked. There are no calls to the EGR cycle or AIR pump anymore.
I do have other questions on the tune but by me being new to the forum, I do not know if I need to start a new thread or continue on this one here. Its not topic related but a Tuner Pro patch question on the Y body O2 calcs and the Y body MAF calcs. Are these OK to load in my tune? I would also like to load a data run and have some information on what might need to be adjusted or if the systems looks ok.

[steveo]

you should already have the y body o2 and maf tables loaded in a stock corvette bin

[lesman]

The first values are my default BIN from my Vette. Now these may have been modified by the HyperTech programmer that I have when I adjusted the fuel for higher octane. The tool they sold for the C4 94-95 LT1 was very limited but I guess for back then it was great. Default octane rating from factory was 89 but this tool moved it up to 91 - 93. It also firmed up shift point and various curves but as I said very limited. Mainly yes or no questions but there was some data entry areas that I did not fool with. Power Programmer Plus. They are right around the corner from my house.
This is a comparision of the bin file taken as backup and the patched file from Tuner Pro. the right hand side is the Tuner Pro patch.
Which ones would be more effective?
18967

[NomakeWan]

I've seen the Hypertech """"tune"""" from the device for the 94-95 Corvette, as my '94 Corvette's previous owner had used it. It's garbage, like most of Hypertech's stuff is. You'll be glad you're just doing the tuning yourself.

I did save a copy of the changed BIN just for reference, but then promptly undid Hypertech's changes and just implemented my own instead.

[steveo]

i would start from scratch with a stock bin and tune from there

[lesman]

I have the factory bin stored in the old programmer so I can push it back into the unit and start from there. I found the 16181333 BKFS bin the file area. My 16181333 has a BKFS suffix also. In case the storage is scrambled, would be this be the upload to start with?
Also, some have said the 16188051 LT1 ecm is a replacement (to a degree) for the 1994 Corvette LT1. I know there was added components in the 16181333 for the future ODBII addtion that didnt come until 1996. It may be a dumb question (and over the years I have asked a many of them), would there be any harm in using this as a tester since I would hate to accidently tank my factory ECM? I have one of them.

[steveo]

you can totally program a y-body bin to the f-body/b-body 8051 ECM and use it in your 'vette. they are interchangeable-ish, the extra code for the diagnostic crap doesn't do anything worthwhile, in fact i have a patch that replaces it with something more useful (a shortened datastream message to get a higher sample rate when logging with eehack)

if you are flashing the 8051 ecm with a y-body bin for the first time in-car you might have to pull the fuse for the CCM for that initial flash, since they will fight over who runs the ALDL bus, in a y-body the CCM runs the aldl bus and in the other cars the ECM does....but my hunch says flashhack will probably figure it out and work anyway after a few attempts.

here's every bin we've found so far, including factory code patches, just pick the one that matches your car and go for it. you could even look at the 1995 bin and get some ideas, i know they revised a few things but the engine itself did not change, but i think you will want to run the 1994 bin they are by calibration ID number not broadcast code though. there are only three choices for a 1994 'vette, and two of them are just different final gear ratios (so speedo calibration and shift points are different)

http://ecmhack.com/tutorials/bin-files/

[lesman]

Yes,
I found the LT1 8051 ecm on a Buick Roadmaster a while back. When I first tested the replacement theory I though the ecm was junk, couldn't talk to it very well in the vette. Searched every where for a solution on why it wasn't talking and in a far away forum, deep into an old thread, was a suggestion that the 8051 gets confused from LT1 to other LT1 models. They said to pull the CCM fuses till it talks. I pulled CCM2 and it came to life. Programmed right up.

I appreciate all the help. Even though the opti has bit me many a time, I still love my vette LT1.

[lesman]

If I start out fresh. What settings do I need to tweak to bring my octane rating up to 93 or 91 minimum?
The default settings from factory has been usually 89 octane. Are the bins set at factory or do they have the higher octane rating applied?

[NomakeWan]

First, an 8051 will work fine in a Vette as long as it has a Vette BIN. kur4o found that address 3AC7 controls whether the PCM tries to be a bus master (such as on F-Body cars) or let a CCM/BCM be a bus master (such as in a Corvette). The latter sets all values to 0.

As for octane, "octane" is not a setting. It's not some magic thing you can just one-click to change. The minimum required octane for your engine depends on several factors that boil down to cylinder temperature and cylinder pressure. Here's some info: http://www.gearhead-efi.com/Fuel-Injection/showthread.php?11618-Engine-temperature-detonation-and-timing&p=97660&viewfull=1#post97660

In short, GM gave the owner's manual its recommendation based on internal testing and lowest-common-denominator philosophy. The PCM also has a Low Octane Compensation mode that retards timing if too much knock is encountered (at least, that's how I assume it works, based on similar compensation techniques from other manufacturers of the era I am familiar with). So if you follow GM's owner's manual recommendation, you'll get what's advertised. If you use 87, you won't get all the performance advertised, but GM will stop you from destroying your engine.

Once you start tuning things for your specific engine, you are now in no-man's land. No one knows your parameters but you. So whether you need to put higher octane fuel in or not depends entirely on your engine configuration as well as your tune.

As a side note, in case you were curious, Hypertech didn't know what octane would be required either--they just gave a blanket recommendation so as to avoid potential lawsuits. Considering how dumb their changes to the tune are, that was probably prudent.

[steveo]

If I start out fresh. What settings do I need to tweak to bring my octane rating up to 93 or 91 minimum?
The default settings from factory has been usually 89 octane. Are the bins set at factory or do they have the higher octane rating applied?

higher octane needs more timing advance to burn completely. so the setting you need to tweak is your timing tables