90mm lightning Maf?

Discussion in '1994 - 1995 Specific Tech' started by 98blackstallion, Apr 24, 2011.


  1. 98blackstallion

    98blackstallion Member

    Joined:
    Mar 31, 2005
    Messages:
    592
    Likes Received:
    0
    Trophy Points:
    17
    Location:
    mtn home arkansas
    Can these be retuned to the injectors I plan on using? Well I gues first can this be used on a 95 gt?
  2. final5-0

    final5-0 Mustang Master

    Joined:
    Apr 7, 2003
    Messages:
    6,817
    Likes Received:
    3
    Trophy Points:
    79
    Location:
    DFW Texas
    I'll get started with a few basics about meters and injectors and others
    will chime in with helpful info I'm sure :)

    First of all you should seperate OEM or in our case ... FORD meters
    and
    The aftermarket meters like ProM, C&L, and the like from each other

    Ford meters are not calibrated to any size injector

    If you get right down to it :D
    meters have nothing to do with fuel or injectors :eek:

    A meter is used to measure airflow :)

    The lightning meter you speak of was designed by Ford to measure the
    amount or maybe better said ... the range of airflow a blown windsor
    motor will generate

    Now ... Having said that .............
    Ford knew for that amount of airflow being generated, they would need
    an injector size of 42 lbs

    The important thing here is this ...
    that meter is not calibrated for injectors with a rating of 42#'s :nono:

    It is the AFTERMARKET industry that started the whole .........
    meter caled to a certain size inj thing

    The motivation behind that method was to provide a way of using larger
    size inj's without having to custom tune OR change the parameters
    inside the pcm

    Basically what is being done with the meter to inj calibration method is
    the meter reports a false reading to the pcm

    You no doubt have seen some talk about this and use the wording ......
    Cheat Method :)

    It worked pretty well on the Fox Stangs
    but
    Not so good with our two year run of 94-95 Stangs

    We won't go into details but the jest of the matter is .........
    the old fox pcm was based upon rpm and our pcm's are load based

    Now with the focus on our Stangs ..........
    You can say these things about using the cheat method

    It works better with the smaller size inj's like 19's and 24's
    but
    With 30's and above you start to deal with issues

    Last but most important thing here about the cheat method :D

    We talked about how our pcm's are load based .........

    It just so happens the meter's output to the pcm is used to determine
    load and when this reading is off ... The foundation the whole tune is
    built upon is all outta whack :crazy:

    When your pcm load factors are not accurate
    Well ... the pcm uses load to determine how much fuel/spark to command ;)

    This can turn out to be a real ....... cluster you know what :rlaugh:

    Also ... One tunes the pcm ... not ... the meter

    Yes ... You can change the data in the pcm to make the lightning meter
    work and MANY have done just that and made it work very well

    Gotta go for now!

    Grady
  3. Gearbanger 101

    Gearbanger 101 we love us some gays up here Super Mod

    Joined:
    Aug 11, 2002
    Messages:
    13,978
    Likes Received:
    620
    Trophy Points:
    164
    Location:
    Ontario, Canada
    In other words, program the correct transfer function into your ECU and you can use any size injectors you want with that meter. :D

    Personally, I'd stick with the 42's unless you're getting really silly with power. You can have them tuned via ECU Chip flash to run just as well as the stock 19lb/hr units for every day driving, yet they're support power levels somewhere near the 450-500fwhp range if need be, which is about where most stock short blocks start to get nervous anyway.
  4. 98blackstallion

    98blackstallion Member

    Joined:
    Mar 31, 2005
    Messages:
    592
    Likes Received:
    0
    Trophy Points:
    17
    Location:
    mtn home arkansas
    Thanks guys for all the insight! that was greatly appreciated! Now My next and last question. Who's the people to see for chip reprogramming? I knew who to see on the modular mustang crowd (sct ect)..My 393 stroker should be built this weekend!

Share This Page