Results 1 to 9 of 9

Thread: New to GM Tuning - 4.3 to 5.7 swap???

  1. #1
    New Member
    Join Date
    Nov 2020
    Posts
    2

    Default New to GM Tuning - 4.3 to 5.7 swap???

    Hello, I did a 5.7 swap in an '03 Sonoma 4x4. I installed an '02 5.7 with an 0411 ECM. I have a small stumble around 2000-2500rpm. I have used older Holly and Accel EFI systems. How would I watch the fuel map live to know where the stumble is to adjust the fuel at that position in the MAP? Or is that not how EFI Live works? Thanks for the help.

  2. #2
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,010

    Default

    Hi Griff,

    What was the donor year/model/vehicle for the 5.7L...?
    Did the 0411 PCM come from same vehicle...?
    How is MAF plumbed (post pics)...?
    Are the front NBO2 sensors being used...?

    Log the following pids:
    SAE.RPM
    SAE.MAF
    SAE.MAP
    SAE.IAT
    SAE.ECT
    SAE.LONGFT1 and 2
    GM.SPARKADV
    GM.KR
    GM.HO2S11
    GM.HO2S21 (watch where the 2 is)
    GM.TP

    You might also need the check that all the spark plugs are and injectors firing under load in the rpm range you indicated (easier said than done).

  3. #3
    Lifetime Member
    Join Date
    Mar 2009
    Posts
    655

    Default

    Also post the tune. Did you start with a van PCM? That's the only 411 that came tuned for a 350. Is the engine modified at all?
    1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
    1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
    2004 Corvette Z06 with longtubes.

  4. #4
    Senior Member
    Join Date
    Jan 2010
    Posts
    136

    Default

    Quote Originally Posted by Supercharged111 View Post
    Also post the tune. Did you start with a van PCM? That's the only 411 that came tuned for a 350. Is the engine modified at all?
    Actually, in Mexico the trucks and the suburban you could still get the old L31 5.7L in it... https://forum.efilive.com/showthread...ghlight=Mexico

  5. #5
    Lifetime Member
    Join Date
    Mar 2009
    Posts
    655

    Default

    Quote Originally Posted by 1FastBrick View Post
    Actually, in Mexico the trucks and the suburban you could still get the old L31 5.7L in it... https://forum.efilive.com/showthread...ghlight=Mexico
    I never realized there were EFILive tunes floating around for those, nice. I'm assuming the OP is using the 512k PCM though.
    1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
    1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
    2004 Corvette Z06 with longtubes.

  6. #6
    Senior Member
    Join Date
    Jan 2010
    Posts
    136

    Default

    Quote Originally Posted by Supercharged111 View Post
    I never realized there were EFILive tunes floating around for those, nice. I'm assuming the OP is using the 512k PCM though.
    Yes, a 411 is a 512K PCM and there are Mexico market based L31 tunes out there for a 512 PCM.

  7. #7
    Senior Member
    Join Date
    Jan 2010
    Posts
    136

    Default

    Here is a 2001 L31 from a mexico market truck 2001 L31 manual.ctz

  8. #8
    Lifetime Member
    Join Date
    Mar 2009
    Posts
    655

    Default

    Quote Originally Posted by 1FastBrick View Post
    Yes, a 411 is a 512K PCM and there are Mexico market based L31 tunes out there for a 512 PCM.
    Is there anything special about a 512k Mexico L31? I thought the appeal of the Mexico L31 was the one that came with the 1MB PCM, thus giving a factory starting point to be able to run the later PCM.
    1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
    1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
    2004 Corvette Z06 with longtubes.

  9. #9
    Senior Member
    Join Date
    Jan 2010
    Posts
    136

    Default

    Quote Originally Posted by Supercharged111 View Post
    Is there anything special about a 512k Mexico L31? I thought the appeal of the Mexico L31 was the one that came with the 1MB PCM, thus giving a factory starting point to be able to run the later PCM.
    I can not think of anything specific.

Similar Threads

  1. New to GM Tuning - 4.3 to 5.7 swap???
    By Griff1999 in forum Vortec V6/V8 Specific
    Replies: 0
    Last Post: November 8th, 2020, 02:00 PM
  2. T76 Transmission / Tuning Swap - I'm stuck!
    By Josh61513 in forum 6 speed/8 speed RWD/FWD Transmission Tuning (incl T43, T76, T87)
    Replies: 1
    Last Post: December 19th, 2012, 08:34 AM
  3. Two Engine Swap Questions (less tuning than converting, really)
    By Admiral Ballsy in forum General (Petrol, Gas, Ethanol)
    Replies: 3
    Last Post: March 10th, 2011, 06:38 PM
  4. I did the 411 swap now tuning?
    By duramaximizer in forum Gen III V8 Specific
    Replies: 6
    Last Post: September 22nd, 2009, 01:00 PM
  5. Engine swap. Tuning help needed.
    By gao8302 in forum Gen III V8 Specific
    Replies: 2
    Last Post: May 14th, 2008, 05:23 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •