Bringing TBI and Multi Port Fuel Injection to a New Level.     EFI Conversions and Tuning! Seattle to Portland! E-mail Tuning Consultant!
Results 1 to 3 of 3

Thread: Main Spark Bias advice needed

  1. #1
    Fuel Injected!
    Join Date
    Feb 2015
    Location
    New Zealand
    Age
    49
    Posts
    176

    Main Spark Bias advice needed

    What do most people here do with there "Main Spark Bias" scalar value?
    I searched a bit and it seems like quite a few people just zero it out, what's the main advantage to 0 as opposed to just leaving (in my case 9.8)?

    I can see how changing the value to 0 instead of 9.8 automatically adds 9.8 to my "Main Spark Table vs, MAP vs, RPM" values.
    In my case that changes my Main Spark Table from 12.3 3600 @ 100 KPA up to a better looking 22.1.

  2. #2
    Fuel Injected!
    Join Date
    Jul 2013
    Location
    Newzealand
    Posts
    475
    Spark biases are so the processor can do minus calculations as it can't do minus numbers .so things like air intake Spark retard tables etc can subtract timing

  3. #3
    Fuel Injected!
    Join Date
    Feb 2015
    Location
    New Zealand
    Age
    49
    Posts
    176
    Thanks for the reply, I've read that the Main Spark Table can't have negative numbers in it and I can see why the factory has bias values to help achieve that.
    I'd like to know why it seems quite popular to just zero it out?

Similar Threads

  1. Replies: 0
    Last Post: 06-13-2016, 09:28 PM
  2. Tuning Advice needed
    By edfiero1 in forum GM EFI Systems
    Replies: 12
    Last Post: 07-29-2015, 10:36 PM
  3. turbo lt1 tuning advice needed
    By supr67 in forum OBDII Tuning
    Replies: 4
    Last Post: 02-13-2014, 03:46 PM
  4. $42, ASDU, SA - PE Spark Added and Warm Bias?
    By shimniok in forum GM EFI Systems
    Replies: 4
    Last Post: 04-30-2013, 03:19 PM
  5. Warm spark bias
    By TheApocalyptican in forum GM EFI Systems
    Replies: 15
    Last Post: 06-05-2012, 01:36 PM

Bookmarks

Posting Permissions

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