Pop Off Valve
+ Reply to Thread
Page 1 of 20 1 2 3 4 11 ... LastLast
Results 1 to 14 of 277

Thread:
Pop Off Valve

  1. #1

    Join Date
    Jun 2008
    Posts
    101

    Default Pop Off Valve

    Yes or No, lets talk

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    Senior Member sdpm's Avatar
    Join Date
    Feb 2008
    Posts
    1,532

    Default

    Yes!

  4. #3
    I'm No Expert Shaun's Avatar
    Join Date
    Feb 2008
    Location
    San Clemente, Ca
    Posts
    3,138

    Default

    Quote Originally Posted by John Mills View Post
    Yes or No, lets talk
    Boy, your really trying to push these things...

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Senior Member TwinTurbo540's Avatar
    Join Date
    Jan 2008
    Location
    spokane, WA
    Posts
    1,164

    Default

    At what speed's and et's are you guys starting to Run these? Do most guys run them because they have a lot of their gear below the keel.?

    Thanks

    Travis

  7. #5
    Amber Racing Services BUSBY's Avatar
    Join Date
    Dec 2007
    Location
    So Cal
    Posts
    4,337

    Default

    yes.

    but a pop off and jet away are both needed IMO for boats that are on the edge

    Quote Originally Posted by TwinTurbo540 View Post
    At what speed's and et's are you guys starting to Run these? Do most guys run them because they have a lot of their gear below the keel.?
    no real speed can be stated ... more of a handling issues on shut down. if the boat blows the tail upon high speed shut down, you could benefit from a pop off.

    when I say "blow the tail", I mean that the pressure in the intake overcomes the down force weight of the hull. it tries to lift the rear of the boat, relieving that pressure will make for better handling.

    every hull is different, so no one speed can be stated.

    so IMO, yes, fast boats need pop offs to be safe.

  8. #6

    Join Date
    Jun 2008
    Posts
    101

    Default

    Quote Originally Posted by BUSBY View Post
    yes.

    but a pop off and jet away are both needed IMO for boats that are on the edge



    no real speed can be stated ... more of a handling issues on shut down. if the boat blows the tail upon high speed shut down, you could benefit from a pop off.

    when I say "blow the tail", I mean that the pressure in the intake overcomes the down force weight of the hull. it tries to lift the rear of the boat, relieving that pressure will make for better handling.

    every hull is different, so no one speed can be stated.

    so IMO, yes, fast boats need pop offs to be safe.
    Why do you believe both are needed, If the jet away does release some of the PSI in the intake wont this affect the auto setting?

  9. #7
    Senior Member Boat 405's Avatar
    Join Date
    Dec 2007
    Location
    San Diego, CA
    Posts
    3,732

    Default

    Quote Originally Posted by John Mills View Post
    Why do you believe both are needed, If the jet away does release some of the PSI in the intake wont this affect the auto setting?
    for warm up.... the only time I've ever heard my jet-a-away is when pulling into the out ramp area and shutting off the motor.

  10. #8
    Senior Member bp298's Avatar
    Join Date
    Dec 2007
    Location
    LHC
    Posts
    6,570

    Default

    Quote Originally Posted by John Mills View Post
    Why do you believe both are needed, If the jet away does release some of the PSI in the intake wont this affect the auto setting?
    jetaway's instantaneous, while the popoff is slightly delayed. the first boat i saw with both was don harris, when he threw his belt right in the lights and still went 135. boat settled in unbelievably smooth and just coasted to a nice easy stop. personally, i don't believe either one by itself will relieve pressure as quickly or as well as both will...

    Quote Originally Posted by BUSBY
    no real speed can be stated ... more of a handling issues on shut down. if the boat blows the tail upon high speed shut down, you could benefit from a pop off.

    when I say "blow the tail", I mean that the pressure in the intake overcomes the down force weight of the hull. it tries to lift the rear of the boat, relieving that pressure will make for better handling.

    every hull is different, so no one speed can be stated.

    so IMO, yes, fast boats need pop offs to be safe.
    glad you clarified that, 'cause that's not "blowing the tail" - it's a severe overload...

    njba rules say 100mph, or highter, boats must have one or the other. ihba rules specify certain category boats that must have popoff valves, most of which would be expected to run in excess of 130. and i agree that fast boats, say those running 120-125 -should- take advantage of every safety device available, and run both.

  11. #9
    Senior Member bp298's Avatar
    Join Date
    Dec 2007
    Location
    LHC
    Posts
    6,570

    Default

    Quote Originally Posted by widowmaker View Post
    for warm up.... the only time I've ever heard my jet-a-away is when pulling into the out ramp area and shutting off the motor.
    try shutting the engine off at, say 100-105 sometime... it's a pretty cool sound, spinning down from max rpm, just like cards in bicycle spokes.. as you're just hopin to stay dry for the next few seconds...

  12. #10
    Senior Member cyclone's Avatar
    Join Date
    Dec 2007
    Posts
    3,620

    Default

    I had a carb issue at a race that only reared its head at the end of a pass when tried to slow down. As soon as i cracked the throttle even the slightest bit the motor would shut off.

    I killed the motor at 119-121 mph on three consequtive passes without a pop off on the boat. the boat settled down nice and straight with the jetaway ratcheting.

    i've got both on the boat now and i gotta say i can get way more aggressive with the hardware now that i can use the pop off to slow the boat down.

    Ive only hit the pop off button a handful of times when the boat got out of shape and it really does help straighten the boat out.

    i recommend both if you're going fast.

  13. #11
    [email protected]
    Join Date
    Feb 2008
    Location
    Ohio
    Posts
    1,011

    Default

    What I've seen is the heavier the boat the better they work. The lighter hulls seem to still hook. I've got video of my light wieght texas tunnel at half track at about 75mph. The impellor broke, stopping the engine. You can see the back of the boat lift off the water. The whole boat was air born a couple inches off the water for a second or two. It landed on the bow and around it went. Needles to say, I cartwheeled 5 times before I stopped. This had no whirl -a- way or pop off. I think the water packed under the boat from the forward momentum and picked it off the water. I think a jet boat should have both. In my case, a whirl -a- way would have done nothing. The pop off would have let pressure out ahead of the impellor.

    Tim

  14. #12

    Join Date
    Jun 2008
    Posts
    101

    Default

    Quote Originally Posted by bp298 View Post
    jetaway's instantaneous, while the popoff is slightly delayed. the first boat i saw with both was don harris, when he threw his belt right in the lights and still went 135. boat settled in unbelievably smooth and just coasted to a nice easy stop. personally, i don't believe either one by itself will relieve pressure as quickly or as well as both will...



    glad you clarified that, 'cause that's not "blowing the tail" - it's a severe overload...

    njba rules say 100mph, or highter, boats must have one or the other. ihba rules specify certain category boats that must have popoff valves, most of which would be expected to run in excess of 130. and i agree that fast boats, say those running 120-125 -should- take advantage of every safety device available, and run both.
    In order for the jetaway to do what the popoff does the impeller with out the help of the motor has to build pressure in the bowl and then squirt it out the nozzle,How is this accomplished? Blown Fever made plenty of passes well above 150 mph and lost the motor in the lights with out a problem so the popoff by its self does work. In response to the question I asked earlier if the jetaway does release some of the intake preasure it will only cause the popoff to delay before it reaches its set point.

  15. #13
    B1 Racing cs19's Avatar
    Join Date
    Dec 2007
    Posts
    6,523

    Default

    some of us dont run that saftey deal. We blow the valve when we want and thats it. yes driver can react very fast when needed, i had an issue last NJBA race and was on the valve right then and aborted the run, it works fine.

    If your only gonna run one of the 2 parts I think the valve is the first to get then a ratchet. There are some fast guys running no ratchet just a valve, they use lenco drivelines to warm up.
    B1Racing.net

  16. #14

    Join Date
    Jun 2008
    Posts
    101

    Default

    Totally agree with you, A manual valve is better than no valve.

+ Reply to Thread
Page 1 of 20 1 2 3 4 11 ... LastLast

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in


Tags for this Thread

Digg This Thread

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •  
 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95