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Thread: Learn Table with Combo tuning (Alpha-N & Speed Density).

  1. #1

    Default Learn Table with Combo tuning (Alpha-N & Speed Density).

    I already have a Speed Density tune. Have a buck at a certain condition that I just can't get rid of. Thinking of trying Alpha-N below a certain RPM. Does Alpha-N:
    A) Use Closed Loop feedback?
    B) Have it's own Learn Table?
    I saw in the EFI software that I can set the transition parameters when it flips from one tune to the other. Just not sure how the Closed Loop & Learn work with Alpha-N.

  2. #2
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    In the EFI software, click "Help", "Contents" & "Step-By-Step Beginners Tuning". Read chapter 8.0, "Alpha-N, VE Tuning & Conversions".
    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.

  3. #3

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    @Qwktrip: What is the nature of your "buck", when does it occur? Andrew

  4. #4

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    Sorry I haven't checked this site in a few weeks. The drivetrain starts to jerk when cruising near 1800 RPM. It'll stay that way until I apply a little throttle or clutch in. It gets started when throttle is really light, like roads with a slight downhill slope. Won't happen at all if engine is above 2000 RPM. Not very likely to happen either if cruising at 1600 RPM either. Kind of gets set off right in that 1800-1900 RPM zone.

    I'm beginning to wonder if it's a resonance in my drivetrain and if changing rear gear could move that to a lower RPM where I don't spend hardly any time. Unfortunately, 1800-2000 RPM is smack dab where the engine sits when cruising on city streets.

  5. #5

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    What's the engine combination? Transmission? Car? Rear gear? Etc.? Andrew

  6. #6

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    How about a datalog when this occurs? My first thoughts would be, pull timing in that MAP range.

    If at -very- light load, less timing will require slightly more throttle opening, which can smooth this out.

    My next question would be, how aggressive is this combination? If running a lot of duration, sometimes the best resolution is to modify your driving style.

  7. #7

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    I used "VE Combo" on some of our SuperStock cars. In fact, I have it on mine. The trick is to match the point where it switches between the two. The Learn Table is not available to the Alpha-N stuff with Combo. All the Learning will show up on the Base Fuel Table, nothing will be on the Alpha-N tables. I just use the lbs per cell and as it rolls through those cells make them linear. The confusing part for me while learning to use this Combo was, you're way up into the MAP kPa numbers when it switches. I had my Combo Alpha-N at 2000 max, but liked it better at 2500. Throttle is 50%. It works really well. One nice thing about these is you never have any issues with dieing after the burnout, or getting "shut off" during a 2-Step process and the car sputters, etc. The camshafts in these cars are huge, .825" lift with 288° of duration @ .050.

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