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Thread: ZZ572 Set-up

  1. #1

    Default ZZ572 Set-up

    Hi from Australia

    I have just bought a 48 Chev pickup with a ZZ572 620hp crate engine and MSD atomic TBI.

    Car is an TH400 and runs pretty good but i was hoping to iron out some issues.



    1) the car surges at light throttle just a little, worse when cold and worse at low rpm.

    2) it gets a bit hot idling, crusing is fine but sitting in traffic at idle it gets too hot ...235+F if you sit there for 10mins, it is hot in Australia (35-38c some days) but truck does have a huge alloy rad good fans for the room available.

    3) I think it lacks a little power has a little dip almost stumble in power when you first get on it or maybe more through the 3-4000rpm range then clears out and goes.

    Set-up.

    Engine and cam specs http://www.chevrolet.com/performance/crate-engines/big-block-zz-572-620.html#dyno



    Fuel system is return with a reg up near engine running big Aeromotive pumps set to 60psi

    Initial setup

    572ci

    8cyl

    Cam Performance

    Idle rpm 825

    AFR 13.2 14.1 12.8

    Ignition setup

    idle rpm 850

    total2700

    idle adv 17.5

    Total 36

    Vac 8

    type ported

    Map reading ignition on motor off 95Kpa, 75Kpa running.

    Any advice would be welcome i hope an msd tech can chime in or someone with experience with this crate engine and confirm things like came setting(is that cam "performance" ???) etc.

    Cheers

    Justin


  2. #2

    Default ZZ572 Set-up

    Just a couple of observations:

    Cam duration is above the recommended 250 degrees max, yours are 254° intake / 264° exhaust.



    Max HP is close to the maximum of 625 supported by this system.



    Idle target is 825 rpm

    Idle is 850, recommended is 100 above target though I have seen 75rpm above target used.



    Nice motor, should wait for MSD tech or someone with more Chevy experience to chime in.



    What part of Australia are you from?

  3. #3

    Default ZZ572 Set-up

    Thanks for the help bojo.

    I'm in Perth Western Australia



    I'm hopefully going to put truck on dyno soon and see where its at and set up Nitrous, i have a fair bit of experience with tuning, EFI mainly so it would be good to know how the MSD does it's thing so i can get the best out of it.



    I have read elsewhere her that the cam setting changes tune street=richest perf=leanest....how does it do this ? is it changing map scaling on a speed density table ? or ?



    Also what effect does the engine size setting have on what ?



    Anything else useful to know to tune/fine tune ?



    What happens with self leaning when nitrous is on ?? will it fight the mixture change ?





    Cheers

  4. #4

    Default ZZ572 Set-up

    Is this forum frequented by MSD technical support people ?

    Is it hear for support of the products or ?



    Anyone from MSD tech willing to way in at all ?



    ...I'm in Australia, i can't really ring the US support number that easy with time difference etc...was hoping for some support here for this MSD product.

  5. #5
    msdtech1955 Guest

    Default ZZ572 Set-up

    Oversteer wrote:

    Hi from Australia



    I have just bought a 48 Chev pickup with a ZZ572 620hp crate engine and MSD atomic TBI.



    Car is an TH400 and runs pretty good but i was hoping to iron out some issues.



    1) the car surges at light throttle just a little, worse when cold and worse at low rpm.

    2) it gets a bit hot idling, crusing is fine but sitting in traffic at idle it gets too hot ...235+F if you sit there for 10mins, it is hot in Australia (35-38c some days) but truck does have a huge alloy rad good fans for the room available.

    3) I think it lacks a little power has a little dip almost stumble in power when you first get on it or maybe more through the 3-4000rpm range then clears out and goes.



    Set-up.



    Engine and cam specs http://www.chevrolet.com/performance/crate-engines/big-block-zz-572-620.html#dyno



    Fuel system is return with a reg up near engine running big Aeromotive pumps set to 60psi



    Initial setup

    572ci

    8cyl

    Cam Performance

    Idle rpm 825

    AFR 13.2 14.1 12.8

    Ignition setup

    idle rpm 850

    total2700

    idle adv 17.5

    Total 36

    Vac 8

    type ported



    Map reading ignition on motor off 95Kpa, 75Kpa running.



    Any advice would be welcome i hope an msd tech can chime in or someone with experience with this crate engine and confirm things like came setting(is that cam "performance" ???) etc.



    Cheers

    Justin









    set the total rpm on the timing down to 2200



    and just for a quick test , lower the vacuum to 0 degrees





    msdforms@msdperformance.com







    Latitude: 31.730125
    Longitude: -106.29673








  6. #6
    msdtech1955 Guest

    Default ZZ572 Set-up

    also :





    when you did the 15 degrees for the timing ...was the hand held in the

    dis abled postion ?





    msdforms@msdperformance.com







    Latitude: 31.730125
    Longitude: -106.29673








  7. #7
    msdtech1955 Guest

    Default ZZ572 Set-up


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