View Full Version : 1998 Black Box PCM Full Flash???

October 4th, 2010, 04:10 AM
Can the older black box pcm's be full flashed and change from a V6 OS to a V8 OS...I have a pcm that I used a license on(vortec V6), I'm about to do a motor swap using a 1998 5.7 Vortec and was wondering if I can just do a full flash and change it to a V8 so I don't burn another license...:D
I ask because I've only full flashed the LS1 PCM's and change from a V6 OS to a V8 OS all the time...

October 4th, 2010, 04:29 AM
Hello Gameover,

I don't do black box Vortec tuning, but I do know the V6 and V8 "Vortec" trucks used the same PCM in any given model year. Not sure if those PCMs have Serv# and HDW# like the LS1-Bs do .... if so, double check that, but you should be OK to reflash the V8 program into the V6 PCM.


October 4th, 2010, 05:50 AM
Just went through this with someone , the part number for the PCM is the same V6-V8 , so should be able to without any problem .

October 4th, 2010, 02:29 PM
Ok cool...:D Gonna try it this week!

October 5th, 2010, 05:35 AM
Can you actually do this in EFILive? I dont remember the full flash option being available when I pulled my buddy's 99 Blazer V6 OS a year back...

October 5th, 2010, 08:15 AM
IDK...gonna try it tomorrow evening though, I'll let you know how it goes...:)

October 10th, 2010, 03:26 PM
I tried it and the FULL Flash option isn't available... So I tried calibration only and it looks like EFI Live wrote over the V6 calibration...:shock:
I did a comparison between the Original V8 tune file and the tune File I just flashed in...NO Differences at all.....so I'm thinking I might be good...:grin:

October 10th, 2010, 03:27 PM
I read the PCM and it looks like there's a 1998 V8 5.7 file in it now!

October 10th, 2010, 04:08 PM
Gameover. If you like post both files. (The stock V8 file you used as well as the file read from the PCM after the conversion)
I can then turn them into a bin file & make sure there is no hidden differences present. It might also be worthwhile doing a complete segment swap on all segments to ensure undefined parameters are changed as well.

October 10th, 2010, 04:45 PM
This is original:1998 Chevrolet Tahoe Truck Automatic L31 5.7 Litre
This is the file I read after the flash: 1998 Vortec 5.7 Frank

October 10th, 2010, 05:48 PM
How do you convert .tun or .ctd to .bin? :secret:

October 12th, 2010, 03:50 AM
Any luck 5.7ute?

October 12th, 2010, 04:37 PM
How do you convert .tun or .ctd to .bin? :secret:

You can use a different commercially/open source available editor and read the file from a bench PCM that you flashed with your proprietary format/different software tool... You can also go hardcore and yank the flash chip and read the image with a hardware programmer. If you do the latter, be sure to reverse the byte order in the binary if you want to be able to open it in the software editors. :angel_innocent:

October 12th, 2010, 04:40 PM

I have heard a few horror stories related to doing a cal-write on those PCMs if the OS's are different... but if it didn't 'brick' it, you should be in good shape.

October 13th, 2010, 07:02 AM

I have heard a few horror stories related to doing a cal-write on those PCMs if the OS's are different... but if it didn't 'brick' it, you should be in good shape.

Hopefully, I didn't brick it...:D It's actually gonna be ready to be fired up this weekend!

January 11th, 2011, 07:24 PM
I ran across this problem years ago........trying to use a 5.7 pcm on a 4.3......I guess they (EFI Live) think
the risk of brickification is too high like on the E40

January 12th, 2011, 12:43 AM
If the PCM is not affected by the cal only flash and does not work correctly as a V8, it is possible that it could be full flashed by a Tech2 and have all of the correct OS and segments written to it. This shouldn't require another license either.

January 12th, 2011, 04:27 AM
Everything went smooth with the cal only flash....Fired right up and owner has been driving vehicle for a couple of months now...:D
The OS's were actually the same "16263425" 4.3 cal only flash to 5.7