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Thread: E40,scales injector and SD tuning

  1. #1

    E40,scales injector and SD tuning

    I modified my stock ls2 injectors (de-capped) and had them flow tested, 730 cc/min @43.5psi, so 80.4lb/hr @ 58 psi. The fuel rail is corvette style filter/regulator and 58psi. I took my 80lbs divided by 2 and made my entire ifr table 40. Increased my stoich by 2x and halved the ivt. I have done all of this to accommodate the turbo setup I am
    working on.

    When I start it up and drive it it operates at 14.7 via my Wide band but some pretty big Ltft at idle and in pe it goes very rich. If I try to switch to a speed density tune to tune, the idle afr is very lean (19-20) so I have not driven it like this. Afr error was reasonable before the injector change and nothing else has been changed.

    My understanding is that this method worked quite well and that I shouldn?t need to tune my ve/maf or scale the whole tune Is this thought process wrong for the E40 ecu? Should I adjust my ve and maf right away in advance mode or have I missed a step? Or should I just proceed to a full %50 scaled tune.

    Thanks for the help. I can post up a tune later. And I do also have a stock tune I can revert to.

  2. #2
    Tuning Addict 5FDP's Avatar
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    You always have to re-calibrate the MAF and VE when you change injector sizes. Putting in the data is only part of it, the airflow model still needs to be gone back over. It would be less off if there were legit 80lb/hr injectors with proper data for that flow rate, instead of decapping the stock injector to make it flow nearly triple what it did before.
    2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.

    If you don't post your tune and logs when you have questions you aren't helping yourself.

  3. #3
    Ok thanks, of course that makes sense I just didn?t expect it to be that far out. The de-capped injectors are supposed to be temporary until I figure out all the limits.

  4. #4
    Tuner in Training nathanhine1977's Avatar
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    E40 injector upgrade 50LB Deatschwerks.

    Hi, is there a tried and tested procedure for the E40?
    I need bigger injectors as I am maxing out my LSA injectors, I would prefer the least amount of trickery involved.
    At the moment I am thinking buying some 50LB @3 bar so 66LB @4 bar,Deatschwerks as the will fit into the stock Flow Rate Vs KPA table.
    I am still unsure what table need to be adjusted.18th April 2020 last good file.hpt

  5. #5
    Senior Tuner Lakegoat's Avatar
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    Under Engine--Fuel--General--modify Flow rate vs kpa (you can only use a max of 63.5) but that should be close enough, Min inj Pulse, Offset vs Volts vs VAC, Short Pulse limit, Short Pulse adder. You should also modify Stoich since most gas nowdays is 14.2. Get the info from your injector supplier.
    2000 Camaro SS 2015 L83 port injected, Whipple 3.0, 4L80E, 8.8 Ford
    2013 Silverado 5.3, 6L80k 8.8

  6. #6
    Senior Tuner LSxpwrdZ's Avatar
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    If you're using a corvette filter/regulator then that is a NON referenced rail pressure system meaning it stays at 58psi at all times. You must characterize your injectors accordingly. Setting it to 40lb/hr across the whole table is not correct. It should have a slope since the pressure is static meaning injector pressure differential will change with vacuum and boost.
    James Short - [email protected]
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