Results 1 to 6 of 6

Thread: Commanded AFR being ignored? Please help

  1. #1
    Tuner
    Join Date
    Mar 2011
    Location
    Florida
    Posts
    57

    Commanded AFR being ignored? Please help

    Gents,
    Attached is a tune file for a 2010 Camaro, it's upgraded with the HPT custom version that replaces the virtual VE with a real VE. I've tuned the cruising areas of the VE and the MAF and started to tune the boost area of the VE and noticed the AFR remained at 14.x when 11.x was being commanded.

    Around the 10:31 time mark of the scan file you'll see what I'm talking about. Any tips would be much appreciated!

  2. #2
    Senior Tuner 10_SS's Avatar
    Join Date
    Mar 2012
    Location
    Detroit, MI
    Posts
    1,320
    your log is showing 12.8-12.9AFR at ~115kpa according to your wideband on my computer. It seems your ok, just keep richening up the area's it's lean and check to see if there's a change in AFR, make sure your three VE tables all match each other.

    You've also got PE enable set to 2000rpm, but these logs are at 1700rpm and your in PE so you must be getting enrichment purely from the boost enrich tables. I heard this can cause delay, which you dont have so dont worry about that now. I would still enable your main PE enable RPM to something like 1000rpm or lower.

    I would reduce your transient enable delay if your running a SC, ignore if your running turbo.

    If your still in tune mode I would increase your max knock retard to 10, from 6 degrees incase something goes wrong (like tip in lean spike as I used to get).

    What are you running for boost? I would guess a turbo but if your running a whipple then you may want to reduce your throttle opening rate just a bit to avoid a nasty pressure spike if you smack the throttle at say anywhere off idle, example: 4000rpm. They pride themselves on instant boost... but it's a bit too instant. I was thinking about adding a restrictor to the boost valve.
    Last edited by 10_SS; 12-13-2012 at 11:16 PM.
    2010 Camaro LS3 (E38 ECU - Spark only). MS3X running complete RTT fuel control (wideband).
    Whipple 2.9L, 3.875" Pulley, kit injectors, supplied MSD Boost-A-Pump, stock pump
    LG Motorsports 1 7/8" Headers - No Cats, stock mid pipe with JBA Axle Back
    ZL1 Wheels/Tires

  3. #3
    Tuner
    Join Date
    Mar 2011
    Location
    Florida
    Posts
    57
    Thanks 10_SS. It's a twin turbo with 12 lbs of boost. The motor is 419ci with 9.7:1 compression.

    I noticed the PE delay rpm was at 2000 too, but thought it was well above that when I was getting into WOT. Nevertheless, I'll reduce it just to be sure.

    The Whipple is a nice SC, a friend has one and had to drop $3K in a 10-rib pulley kit to get to 14psi.
    Last edited by RookieTuner; 12-14-2012 at 04:55 PM.

  4. #4
    Senior Tuner 10_SS's Avatar
    Join Date
    Mar 2012
    Location
    Detroit, MI
    Posts
    1,320
    Quote Originally Posted by RookieTuner View Post
    Thanks 10_SS. It's a twin turbo with 12 lbs of boost. The motor is 419ci with 9.7:1 compression.

    I noticed the PE delay rpm was at 2000 too, but thought it was well above that when I was getting into WOT. Nevertheless, I'll reduce it just to be sure.

    The Whipple is a nice SC, a friend has one and had to drop $3K in a 10-rib pulley kit to get to 14psi.
    Some people see delay entering PE, part of it may be related to transitional fuel, so sooner is better. Being a turbo you generally wont have full/excess boost at tip in like the Whipple has so you should be ok either way.

    $3K for 14psi? Was that on an already high base HP engine? I like the whipple minus the heat soak and this $3K pulley kit.
    2010 Camaro LS3 (E38 ECU - Spark only). MS3X running complete RTT fuel control (wideband).
    Whipple 2.9L, 3.875" Pulley, kit injectors, supplied MSD Boost-A-Pump, stock pump
    LG Motorsports 1 7/8" Headers - No Cats, stock mid pipe with JBA Axle Back
    ZL1 Wheels/Tires

  5. #5
    Tuner
    Join Date
    Mar 2011
    Location
    Florida
    Posts
    57
    Quote Originally Posted by 10_SS View Post
    Some people see delay entering PE, part of it may be related to transitional fuel, so sooner is better. Being a turbo you generally wont have full/excess boost at tip in like the Whipple has so you should be ok either way.

    $3K for 14psi? Was that on an already high base HP engine? I like the whipple minus the heat soak and this $3K pulley kit.
    He started getting bad belt slip when he went to a 3.25" pulley on the stock 6-rib pulleys. He was going to upgrade to an 8-rib kit for around $1,800 but given the difficulty changing all the pulleys he decided to go straight to 10-rib.

  6. #6
    Senior Tuner DSteck's Avatar
    Join Date
    Mar 2008
    Location
    St. Louis, MO
    Posts
    4,856
    MAF is pretty bad. You're not in straight MAF either which will make it hard to tune the MAF, or VE independently for that matter.

    Start with this attached file and work on your MAF.

    DSX Tuning - Authorized HP Tuners Dealer
    http://www.dsxtuning.com
    http://www.facebook.com/dsx.tuning
    Just say no to bull s***.
    IF YOU WANT HELP, POST A FILE!