msd 7 box firring alky help

Discussion in 'PSI Superchargers Tech Questions' started by rowalton, Apr 1, 2011.

  1. rowalton

    rowalton New Member

    Joined:
    Mar 14, 2011
    Messages:
    38
    Likes Received:
    0
    looking for help ignition i have 540 11.8 static comp 8 71 with 10 # boost bau hat 760 pump i have digital msd 7 box will that fire the plugs or will i need to go to mag thanks
     
    #1
    rowalton, Apr 1, 2011
  2. steve3410

    steve3410 New Member

    Joined:
    Sep 5, 2008
    Messages:
    28
    Likes Received:
    0
    We run the digital 7 on our blown sbc. We have a 8-71 running 10 over and have been 6.8's so far.the only trouble We had was fouling on the two step at wot but only because We were way out rich.
    Steve
     
    #2
    steve3410, Apr 2, 2011
  3. Don Onimus

    Don Onimus New Member

    Joined:
    Feb 28, 2009
    Messages:
    1,337
    Likes Received:
    0
    Msd 7

    Don't even mess with it. I have seen them run, but there are times it sounds like it is on the limiter. Not firing all the fuel. Just put in a Mallory, or a 12 MSD. and it will be one less thing to worry about. Just my thoughts. Don
     
    #3
    Don Onimus, Apr 2, 2011
  4. BlownAlkyMopar

    BlownAlkyMopar Member

    Joined:
    Jul 12, 2009
    Messages:
    39
    Likes Received:
    0
    MSD 10 Plus

    I love my MSD 10 Plus on my Blown Hemi
     
    #4
    BlownAlkyMopar, Apr 3, 2011
  5. visionary

    visionary New Member

    Joined:
    Jul 18, 2009
    Messages:
    36
    Likes Received:
    0
    i ran a msd 7 for years and carried a old 6al for a spare. i actually ran my fastest time ever 7.36 in that car using the old 6al. this was in a 48 fiat alterd running a BBC standard helix 14-71 15 over
     
    #5
    visionary, Apr 3, 2011
  6. wagspe208

    wagspe208 Member

    Joined:
    Dec 20, 2006
    Messages:
    136
    Likes Received:
    1
    A 7 will be just fine IF your mixture is reasonable. IF your mixture is way out of wack (like you have a big ass pump with little boost) God himself will have problems.
    See, will it work... yes... 10# and 11.8 ain't nothing for a 7. 10# and 11.8 with 3x the fuel you need could be a problem.
    It will NOT be an ignition problem, though. It is a tuenup issue.
    Make sense?
    I have run a 7al in my 8.0 boat for 10+ years. My tuneup is right, though. It has run just dandy up to 20# boost with a 600 pump and 80ish pill. No problem. (oh, this was a 6.0 @ 1000' tuneup)

    Wags
     
    #6
    wagspe208, Apr 3, 2011
  7. Kendrick Roberts

    Kendrick Roberts Member

    Joined:
    Dec 10, 2008
    Messages:
    62
    Likes Received:
    0
    We are currently running a 7AL-2 in an altered that runs 6.50@209 with a 14-71 at 20# boost.
    They are correct in telling you that if the tune up is off it will miss like it is on the two step, you can use this to help you tune as you find your "sweet spot".
    One of the things that helped us a lot with this ignition was a 0.015" plug gap because this probably is the weakest ignition that you can get away with, and the tighter gap makes it easier for the lower spark output to be able to bridge the gap.
    You want to keep in mind that if you decide to go to something much hotter - like a mag- it will have a similar effect as advancing the timing, so when you change you will want to back it down a bit and then sneak back up on it.

    Just my $0.02 worth.
     
    #7
    Kendrick Roberts, Apr 4, 2011
  8. caseyspradlin

    caseyspradlin Member

    Joined:
    Sep 9, 2008
    Messages:
    214
    Likes Received:
    0
    msd 10+ no spark help

    search the subject tread and read the tips there they will help.

    thread is

    "msd 10+ no spark help"
     
    #8
    caseyspradlin, Apr 4, 2011

Share This Page





XenPorta 2 PRO © Jason Axelrod from 8WAYRUN.COM