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Manbearpig
February 18th, 2010, 04:32 PM
I have a 2004 GMC Sierra with the LM7 5.3

I'm taking a trip next week and would like to throw on lean cruise.

I don't have a wideband or anything, still need to get one.
Just looking for some insight as to how I would go about this.


Thanks guys.
ScarabEpic22
February 18th, 2010, 04:36 PM
I dont believe you can run the LC patch on 03-08 LS1 PCMs as they are 1MB flash vs 512kb.

I may be wrong, but Ive only heard of 98 (with 99+ PCM conversion)-02 cars/trucks using LC.
Manbearpig
February 18th, 2010, 05:07 PM
Aww hell :(
chevy052500hd
February 18th, 2010, 07:51 PM
I have a 1mb pcm running lean cruise... if you have the tables then it is in there. Just download the patch to enable those tables
Manbearpig
February 18th, 2010, 08:21 PM
I have a 1mb pcm running lean cruise... if you have the tables then it is in there. Just download the patch to enable those tables

Where do I go to download the patch? If I can edit the tables are they already enabled?

< Noob

Thanks
ScarabEpic22
February 18th, 2010, 10:58 PM
I have a 1mb pcm running lean cruise... if you have the tables then it is in there. Just download the patch to enable those tables

Really?! Thats great news, I didnt know 03-08 PCMs had the .cax to enable LC!

Manbearpig, check out the links in this subforum: CAX File forum (http://forum.efilive.com/forumdisplay.php?f=74)
Manbearpig
February 19th, 2010, 09:02 AM
I honestly don't know what I need to be looking for.:doh2:
joecar
February 19th, 2010, 10:10 AM
You would have to know the byte address/offset inside the binary file for parameters you want, and you have to know the format of the parameter data (bit width, signed/unsigned, little/big endian, scaling)...

i.e. you would have to reverse engineer them for your calibration.
Manbearpig
February 19th, 2010, 11:27 AM
So, I'm assuming it's going to be a fairly difficult process to get it going? :laugh:
Manbearpig
February 19th, 2010, 01:06 PM
Alrighty, well I found the LC patch and enabled it.
Going to try out the LC tables from a stock 04 Monaro tune.

See if it helps me out any.

Not quiet certain if I want to run the lean cruise yet on my trip next week. Kinda worried about running it that long lean without a wideband
joecar
February 19th, 2010, 01:17 PM
Does the cax filename match your OS id...?
Manbearpig
February 19th, 2010, 01:25 PM
Yessir
joecar
February 19th, 2010, 01:30 PM
Ok, you should be fine.
Manbearpig
February 20th, 2010, 03:56 PM
Flashed it over

Tests were for 3 miles
20.1 mpg on flat grounds @ 71
21.1 mpg on flat grounds @ 66-67
18.1 mpg on upwards inclines and flat grounds(mostly incline) @ 71
It was commanding 15.5-15.81:1 during these tests.

Even had some fun with the G80 on the way home
http://i6.photobucket.com/albums/y222/Americanmetal071/Mobile%20Uploads/0_IMAG0053.jpg
chevy052500hd
February 21st, 2010, 08:06 PM
did a avay with a 5.3l, it likes 16.5 afr commanded, netted around 23 - 25mpg depending on driving conditions. Owner about shit since it was getting 16 - 18 LOL .. these are highway of course.
joecar
February 21st, 2010, 09:37 PM
...
Even had some fun with the G80 on the way home
http://i6.photobucket.com/albums/y222/Americanmetal071/Mobile%20Uploads/0_IMAG0053.jpgYour posi tests out good/AOK... :hihi:
Manbearpig
February 22nd, 2010, 02:27 AM
did a avay with a 5.3l, it likes 16.5 afr commanded, netted around 23 - 25mpg depending on driving conditions. Owner about shit since it was getting 16 - 18 LOL .. these are highway of course.

Like those mpg numbers :hihi:


Your posi tests out good/AOK... :hihi:

:hihi:
RevGTO
February 22nd, 2010, 04:46 AM
I got it going and it certainly works ... I'm getting as high as 16.4-16.7 @45-50mph on flat surface. This is using stock 2004 Monaro LS1 settings.

I have some more test driving to do at freeway speeds, but is this excessively lean?
Chevy366
February 22nd, 2010, 08:10 AM
I got it going and it certainly works ... I'm getting as high as 16.4-16.7 @45-50mph on flat surface. This is using stock 2004 Monaro LS1 settings.

I have some more test driving to do at freeway speeds, but is this excessively lean?

No , I have seen that with my 6.0L , at that load it should not hurt , have seen someone post that they were seeing as much as 17.1 with LC at cruise Holden platform .
Wolfie
February 22nd, 2010, 08:16 AM
I have been consistently running in the 17's for over 100,000 miles with no
problem. I was told the cats would cause problems, so I just "let them
sort of leak out of their shells) -ie: no cats. ((oops, I didn't say that))
Manbearpig
February 22nd, 2010, 11:12 AM
So you guys are creeping 16:1+ with the holden tables?

I was given some tables with a little less aggressiveness in the target afr on performancetrucks
5.7ute
February 22nd, 2010, 11:52 AM
High 16's are quite the norm on the Holden platform. IIRC mine was between 16.8 - 17.0 AFR on the old engine. I dont use LC now I am running a COS as some strange issues were occurring.(rich cruise mode for example)
vzsv8
March 7th, 2010, 01:38 PM
Hi, as far as destroying cats with LC, I just dont believe it. There is a world of difference between lean under load and lean cruise. At LC the cats should just switch off and cool off, after all there is less fuel for them to burn to keep warm.
I have seen cats taken off factory equiped LC Holdens with over 200,000 km and the only damaged ones were suffering from high load fuel starvation from a worn out fuel pump.
My theory is that peak temp is around 14.7 and it drops lower on either side.
I have just installed a K type thermocouple and when I get time for a cruise I will post up some numbers.
Cheers, Steve