Results 1 to 2 of 2

Thread: AFR Tuning

  1. #1

    Default AFR Tuning

    Hi, I have the Avenger EFI 900 CFM TBI kit. My question is, I have the AFR ratio for idle at 14.7:1, idles very smooth, the cruise at 16.1:1, and the WOT at 13.0:1. At 68-70 MPH, 1950-2000 RPM, the AFR is running at 15.7-16.1:1, runs super smooth, getting great mileage, this is with an automatic overdrive. As I slow down to 60-62 MPH, the AFR drops to about 14.1-14.4, then if slower at 50-55, it drops to 13.1 to 13.5. It still runs smooth but I feel I'm leaving some gas mileage on the table. The TPS is at about 7-8% at 70, and about 4-5% at 55. With less MPH & load, the AFR should be closer to the 16.1, will the computer eventually compensate for this or will I need to hook up to a computer to alter this? My CL Comp is at 1-3% at all three levels. Thanks.

  2. #2
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    25,514

    Default

    Quote Originally Posted by steve tune View Post
    With less MPH & load, the AFR should be closer to the 16.1, will the computer eventually compensate for this or will I need to hook up to a computer to alter this? My CL Comp is at 1-3% at all three levels.
    Since the Closed Loop Compensation is that tight, the Learning has most likely finished self-tuning the Base Fuel Table.
    Good fuel economy is a direct result of the fine-tuning performed on the EFI system, using a laptop computer.
    But TBI is inherently less efficient and the Target AFR will sometimes linger behind due to wall-wetting (X-Tau Fuel).
    Only certain segments of the EFI Tables (idle, cruise & WOT) can be adjusted with the hand-held controller.
    A laptop computer provides full programming control. As you know, the Avenger EFI can also be tuned with a laptop.

    I'm sure you'll find pages 4-10 of this Edelbrock EFI tuning manual very interesting:
    https://edelbrock-files-v1.s3.amazon...ers-manual.pdf
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS T/W 11R 205 heads, 232°-244° duration/.623" lift/114° LSA camshaft, 12:1 C/R, TFS R-Series FTI ported intake, BBK 80mm T/B, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 200A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, -6AN fuel system plumbing, Walbro 255 LPH pump, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/3000 RPM converter, B&M Hammer shifter, FPP aluminum driveshaft, FPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 M/T Street Comp tires.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
About us
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors have powered every NASCAR® Sprint® Cup team and nearly every NHRA® Pro–Stock champion for four decades. Now, Holley EFI is dominating the performance world as well as our products for GM's LS engine. Holley's products also include performance fuel pumps, intake manifolds & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies - Hooker Headers, Flowtech Headers, NOS Nitrous, Weiand, Earl's Performance Plumbing, or Diablosport - Holley products can give you the edge you need over the competition.
Join us