Lean Cruise Tables
#41
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A higher cat temp might make it work better. I am not sure. The cat temp has to be regulated either way.
One thing I do know is that after you go leaner than 14.8-14.9 there is alot more NOXs being produced. If you get 5% better processing at that higher temp and you produce 10% more NOXs then you are still loosing.
That would be the only explanation I could think of. I have a graph of CO CO2 NOXs ect v. AFR at home. I could post it.
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One thing that interests me is that I have EFI Live and I am fairly sure it can not flash an uncompressed binary. Hmm.....
One thing I do know is that after you go leaner than 14.8-14.9 there is alot more NOXs being produced. If you get 5% better processing at that higher temp and you produce 10% more NOXs then you are still loosing.
That would be the only explanation I could think of. I have a graph of CO CO2 NOXs ect v. AFR at home. I could post it.
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One thing that interests me is that I have EFI Live and I am fairly sure it can not flash an uncompressed binary. Hmm.....
#42
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Lean cruise has been banned in the US for emissions reasons only. Below is a graph dipicting why.
From what I've read (http://www.designnews.com/index.asp?...Dthirty%2Byear), you need get the AFR closer to 28:1 to get all polutants to equal the same as our 14.7:1
Running lean cruise on mine I can pull down about 26 MPG on the hwy with 380 RWHP and AC Glad I drive a Holden
From what I've read (http://www.designnews.com/index.asp?...Dthirty%2Byear), you need get the AFR closer to 28:1 to get all polutants to equal the same as our 14.7:1
Running lean cruise on mine I can pull down about 26 MPG on the hwy with 380 RWHP and AC Glad I drive a Holden
#45
I am more than happy to help with this but for me I just wonder if I should skip it and go to the gto pcm/code (since I have my car setup as '98 camaro tune)
older gm pcms (fully hacked code already) are easy as it was there as well but only required a simple enable in the code. it sounds like this maybe along the same line just a few more unknown hoops to jump through
just was wondering if a oversea f-body would have it enabled?
older gm pcms (fully hacked code already) are easy as it was there as well but only required a simple enable in the code. it sounds like this maybe along the same line just a few more unknown hoops to jump through
just was wondering if a oversea f-body would have it enabled?
#46
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This article is interesting. This guy claims all Motorola 68332's have a special on board port with which you can set the break points, step through code, ect
http://www.diy-efi.org/gmecm/ecm_info/32bit/dumpflash/
This means if you had the interface from Motorola you should be able to program any PCM with a 68332 and dump or upload a bin.
It could be worth it to search the OEM site and see if such a device is offered. This guy built an interface but it only works with windows 2000 and is slow.
http://www.diy-efi.org/gmecm/ecm_info/32bit/dumpflash/
This means if you had the interface from Motorola you should be able to program any PCM with a 68332 and dump or upload a bin.
This article describes how to make a simple modification to your 68332 based GM computer to allow you to dump and reprogram the flash. It operates using the BDM port that is built into every Motorola 68332 processor. The BDM port is normally used during software development to allow the programmer to single step through the code, set breakpoints, examine memory, etc. The BDM port has complete access to the CPU and everything connected to it. In this case that means it can read the contents of the flash, and also reprogram it.
It could be worth it to search the OEM site and see if such a device is offered. This guy built an interface but it only works with windows 2000 and is slow.
#48
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You can find information on the BDM interface in the CPU reference manual. I am not sure why you would want to go to the effort of modifying the PCM to incorporate the interface, as you already have a method of dumping and flashing the memory. Additionally, unless you plan on building a bench harness for the PCM (with the ability to simulate sensor inputs), having access to the BDM is useless; with the PCM in the car, the ability to set breakpoints is equivalent to having a kill-switch. You would be better off finding a disassembler/debugger for the 68332 (hint: IDA).
You have all the information needed in the thread to modify your binary to enable lean cruise (at least for EFILive/Tunercat people). I'm almost positive EFILive is using ZLib to compress the tunes. Aside from that, you know what to search for in the disassembly (or hex, if you choose to use such) and how to calculate the checksum for the operating system.
You have all the information needed in the thread to modify your binary to enable lean cruise (at least for EFILive/Tunercat people). I'm almost positive EFILive is using ZLib to compress the tunes. Aside from that, you know what to search for in the disassembly (or hex, if you choose to use such) and how to calculate the checksum for the operating system.
#50
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I got the pro IDA tonight and am loading it up now. The problem was I had the free IDA but it wouldn't decompile anything other than Intels. I got the license for an IDA Pro program tonight from a computing friend. This is a 500 ish dollar program for anyone wondering.
The problem I wonder about now is if I mod the bin I have to have tunercats to upload it as an uncompressed bin with or without checksums.
I know what a library is but I will have to figure out more about what segments are and are not in the .tuns to use EFI-Live to flash my PCM. Also, I need to look up more about Zlib. One of my computings friends said he might be able to help with this part.
My line of thinking was that I could upload an uncompressed bin to the PCM through the BDM without having to buy tuner cats or learn how to mod this to work with EFI Live.
Either way I am having fun learning about this.
The problem I wonder about now is if I mod the bin I have to have tunercats to upload it as an uncompressed bin with or without checksums.
I know what a library is but I will have to figure out more about what segments are and are not in the .tuns to use EFI-Live to flash my PCM. Also, I need to look up more about Zlib. One of my computings friends said he might be able to help with this part.
My line of thinking was that I could upload an uncompressed bin to the PCM through the BDM without having to buy tuner cats or learn how to mod this to work with EFI Live.
Either way I am having fun learning about this.
#51
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I got the pro IDA tonight and am loading it up now. The problem was I had the free IDA but it wouldn't decompile anything other than Intels. I got the license for an IDA Pro program tonight from a computing friend. This is a 500 ish dollar program for anyone wondering.
The problem I wonder about now is if I mod the bin I have to have tunercats to upload it as an uncompressed bin with or without checksums.
I know what a library is but I will have to figure out more about what segments are and are not in the .tuns to use EFI-Live to flash my PCM. Also, I need to look up more about Zlib. One of my computings friends said he might be able to help with this part.
My line of thinking was that I could upload an uncompressed bin to the PCM through the BDM without having to buy tuner cats or learn how to mod this to work with EFI Live.
Either way I am having fun learning about this.
The problem I wonder about now is if I mod the bin I have to have tunercats to upload it as an uncompressed bin with or without checksums.
I know what a library is but I will have to figure out more about what segments are and are not in the .tuns to use EFI-Live to flash my PCM. Also, I need to look up more about Zlib. One of my computings friends said he might be able to help with this part.
My line of thinking was that I could upload an uncompressed bin to the PCM through the BDM without having to buy tuner cats or learn how to mod this to work with EFI Live.
Either way I am having fun learning about this.
I wrote up a quick test file that attempts to decompress a *.tun from EFILive into raw binary. I saved one of the raw bins with EFILive and attempted to convert back to binary, but haven't gotten much in the way of expected output (besides having a plain-text header and 512kb of some odd data).
If it weren't for the fact that the text in the header of the tune decompressed properly, I would think the Zlib inflate routine had been modified.
#53
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EFILive will only download PCMs into a .tun
I have been thinking about getting tunercats because there are several people in the area with 1997 vortecs that want tunes. This should also allow me to get a .bin of the cos5
#54
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Do the 97 vortecs have the tables you guys are trying to get to?
And still unsure why going thru this when you can do the same thing with alot less effort with the tables that are already there in the sw packages.....
And still unsure why going thru this when you can do the same thing with alot less effort with the tables that are already there in the sw packages.....
#55
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If we followed your logic, we would still be tuning by adjusting IFR values and leave everything else stock.
#57
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A couple of people in my area wants tunes on their 1997 vortecs. Not lean cruise tunes just regular fueling tunes. I thought I could charge them and then buy Tunercats with the money. Since EFI Live won't do their vehicles anyways.
Two birds with one stone.
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Good luck with it all and I hope it is worth it. Does seem cool to unlock it on the other platforms though....if this could be done with the LT1s the market would explode, might could convince me to buy what is needed....