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Using VE% Table for estimating horsepower?

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  • #16
    Yes: http://forums.holley.com/showthread....2523#post62523 (Read 4th & 5th Paragraphs - Smooth Fuel Graph After Transfer Learning)
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385"/6.3L SBF, Dart SHP 8.2 block, forged steel crank & rods, forged pistons, Trick Flow T/W 11R 205 CNC comp ported heads, 12:1 comp ratio, 232-244 duration/.623" lift/114 LSA camshaft, TFS R-Series FTI comp ported intake, BBK 80mm T/B, Holley Dominator MPFI & DIS, Holley 36-1 crank trigger, MSD 1x cam sync, PA PMGR starter, PA 200A 3G alternator, Optima Red battery, 100HP progressive dry direct-port NOS, R134a A/C, Spal dual 12" fans, Frostbite 3-core aluminum radiator, Pypes dual 2.5" exhaust, off-road X-pipe, shorty headers, Earl's -6AN fuel system plumbing, Walbro 255 LPH in-tank pump & Pro-M -6AN hanger, S&W subframe connectors, BMR upper & lower torque box reinforcements, LenTech Strip Terminator wide-ratio AOD, 3000 RPM C6 converter, B&M Hammer shifter, Stifflers transmission crossmember & driveshaft safety loop, 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.

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    • #17
      I normally do manually smooth after Transferring Learning To Base. I do it on the Base Fuel Table by hand, which seems easier than on the Fuel Graph. My latest tune could use a little work though. I had recently added the new spacer so I allowed the Learning to do its thing for a bit, so this is the first time I'm really smoothing it all out since then.

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      • #18
        @chevelle502: I smooth manually, but I have a good understanding of what things need to look like. The Learn Table is a guide. Andrew
        Instagram: @projectgattago
        Offering remote Holley EFI tuning.
        I deliver what EFI promises.
        Please get in touch if I can be of service.

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        • #19
          I have continued my pursuit in understanding tuning and I'm trying to make more sense of the VE% Table, past just the basics.

          I recent watched a video of a guy building a tune mostly from scratch. For all I know it could be one of you all (MrAllan5oh is the name on YouTube). Anyway, he made a statement, which made sense to me:
          "The location in the VE% Table with the highest number correlates to your higher torque".

          I have always wondered why my VE% Table seemed to have a bulge started at 3400 and ending 4200 RPM with it centered around 94 kPa @ 3900 RPM. My gut would have said closer to my RPM limit, which is 5800 or so RPM.

          After watching the video I took a look at the spec that Chevy lists for peak torque of my ZZ502 and they claim 580 TQ @ 3600 RPM and 502 HP @ 5200 RPM. Now, I have a bit better heads and a slightly bigger CAM, along with things like (of course) the Sniper and a 1" spacer, dual-plane manifold, full headers, etc. So it seems believable that my max torque is a few hundred RPM higher than stock, and that my VE% tuning and Sniper Learning are likely on track.

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          • #20
            The Holley Sniper/Avenger/Terminator/Terminator X/HP/Dominator EFI LB/HR Fuel Graph looks like the engine's horsepower curve.
            The Holley Sniper/Avenger/Terminator/Terminator X/HP/Dominator EFI VE % Fuel Graph looks like the engine's torque curve.
            May God's grace bless you in the Lord Jesus Christ.
            '92 Ford Mustang GT: 385"/6.3L SBF, Dart SHP 8.2 block, forged steel crank & rods, forged pistons, Trick Flow T/W 11R 205 CNC comp ported heads, 12:1 comp ratio, 232-244 duration/.623" lift/114 LSA camshaft, TFS R-Series FTI comp ported intake, BBK 80mm T/B, Holley Dominator MPFI & DIS, Holley 36-1 crank trigger, MSD 1x cam sync, PA PMGR starter, PA 200A 3G alternator, Optima Red battery, 100HP progressive dry direct-port NOS, R134a A/C, Spal dual 12" fans, Frostbite 3-core aluminum radiator, Pypes dual 2.5" exhaust, off-road X-pipe, shorty headers, Earl's -6AN fuel system plumbing, Walbro 255 LPH in-tank pump & Pro-M -6AN hanger, S&W subframe connectors, BMR upper & lower torque box reinforcements, LenTech Strip Terminator wide-ratio AOD, 3000 RPM C6 converter, B&M Hammer shifter, Stifflers transmission crossmember & driveshaft safety loop, 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.

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            • #21
              Good simple explanation, more HP needs more fuel.

              HP is the rate of torque production with respect to time (it is a derived value). Torque falls off at high RPM as the engine becomes less efficient (actual VE% declines). Similarly, VE% Table must be lower at part-throttle since the engine inlet is restricted.

              Please remember that here the VE% Table is only an estimate by the ECU and not a measured value from a dyno.

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              • #22
                @Candu SNO: I'm guessing the numbers are not absolutely correct, but they're "relatively" correct. And that you can use the VE% Graph to see where your peak TQ is, you just can't specific just what that number is.

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                • #23
                  Not really, the only way to actually know VE% is to measure the intake airflow and compare it to the engine displacement. In a Speed/Density EFI system, the VE% Table is an educated guess by the ECU. The VE% Table is the basis of the Base Fuel Table, which is thus also only a clever guess until it's corrected by feedback from the WBO2 sensor using the Target AFR.

                  Holley's setup Wizard only "knows" engine displacement and cam type, a typical torque curve is then assumed. The VE% Table looks like a torque curve because it is calculated to do so, but it's not your engine's torque curve only a generic one.

                  The HP you want to estimate is rated at WOT, but that portion of the Base Fuel Table is not "Learned" and it's also conservatively rich on purpose. This means that using Fuel Flow and an assumed Specific Fuel Consumption will overestimate HP.

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