Launch Rpm for Bruno?

Discussion in 'PSI Superchargers Tech Questions' started by OwnBlock, Dec 18, 2013.

  1. OwnBlock

    OwnBlock Member

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    whats a good launch rpm, tad, bruno, B & J w / 1.51 low gear, screw hemi, 508ci, 10000 rpm +
     
    #1
    OwnBlock, Dec 18, 2013
  2. jody stroud

    jody stroud ZOMBIE Top Dragster

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    Try 4000 rpms. It works for a lot of racers with automatics.
     
    #2
    jody stroud, Dec 21, 2013
  3. Mike Canter

    Mike Canter Top Dragster
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    Another factor in selecting a launch RPM is if there is a timing control on the motor. If no timing control computer then it would be a lower launch rpm than a motor with a timing computer.
     
    #3
    Mike Canter, Dec 21, 2013
  4. OwnBlock

    OwnBlock Member

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    No timing control
     
    #4
    OwnBlock, Dec 21, 2013
  5. jody stroud

    jody stroud ZOMBIE Top Dragster

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    Yikes !!!!! She's gonna be a little violent. Your going to just have to play with her at the hit
    Maybe add an air throttle.
     
    #5
    jody stroud, Dec 21, 2013
  6. Mike Canter

    Mike Canter Top Dragster
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    The other option is to adjust the converter fluid pressure on the Bruno. You can go down to 110 psi which will soften the hit. In case you don't know. You warm the Bruno up then bring the motor up to around 3000 in neutral and read the pressure on the gauge. If the needle is jumping around then you can come up in rpm until it stops jumping and read the pressure. The allowable range is 110 to 240. 110-140 is soft on the hit, 140-200 is medium on the hit and 200-240 is hard on the hit.
     
    #6
    Mike Canter, Dec 22, 2013
  7. rb0804

    rb0804 Active Member

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    Are you running a Bruno Mike? Are you referring to the dual pressure regulator that some of the turbo guys use?
     
    #7
    rb0804, Dec 22, 2013
  8. Mike Canter

    Mike Canter Top Dragster
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    Referring to the Bruno Converter fluid pressure adjustment on the drivers side of the unit. Not the dual pressure unit on a turbo unit
     
    #8
    Mike Canter, Dec 22, 2013
  9. overkill69

    overkill69 Member

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    Mike have you seen actual results playing with the charge pressure.? I have done mods in the Bruno and converter that made major changes in pressure and never really saw anything on the time slip. It made huge differences in fluid temperature .
    I know of more mods that can stabilize the pressure down track even further but I'm not convinced it really does anything.
     
    #9
    overkill69, Dec 22, 2013
  10. Mike Canter

    Mike Canter Top Dragster
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    How much it would change the launch would depend on the converter and gear ratio and how you are leaving. You are right that it doesn't make a real big difference but it can be used to find tune the launch. Yes it would change the fluid temp because it would change how much the converter is slipping.
     
    #10
    Mike Canter, Dec 22, 2013
  11. bruce mullins

    bruce mullins Top Dragster

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    if you use one of those coolers in the pits that circulates the fluid, does it circulate the fluid in the converter as well in a bruno?
     
    #11
    bruce mullins, Dec 22, 2013
  12. OwnBlock

    OwnBlock Member

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    yes, if you feed it in through the pressure gauge hole.

    thanks heaps for the help and advice, thanks also to dean at dmp awnings, heading off to run the car in 6 days time
     
    #12
    Last edited: Dec 23, 2013
    OwnBlock, Dec 22, 2013
  13. overkill69

    overkill69 Member

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    launch

    you'll have a lot more fun with a timing control on it. 8973's are cheap,effective and easy to use.
     
    #13
    overkill69, Dec 24, 2013

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