Coming Back to Life

การสนทนาใน 'Drag Racing' เริ่มโดย Dr. Jeff Harper, 27 กุมภาพันธ์ 2008

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  1. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    Khun Dee,

    Thanks for the note Wow! That Camero project looks great. As you know, they are going to lengthen the Bangkok Drag Avenue track by an additional 300 (?) meters of shut-down area, so a "Pro Mod" type of car becomes more realistic here. I hope they will spray the track for better traction . . . it's already pretty good, but a Pro Mod will need more traction than there is available right now. Let me know when you are back in Thailand; I would like to come over to your shop and talk about my new project.

    I was at the track last Saturday night, but there weren't very many cars present . . . and the organization and running of the event was very slow. I finally got to run a time trial a round midnight, and try to qualify at 1:30am for the 12.90 bracket (they didn't have enough cars for the 11.90 bracket, so they refunded the money). Of the six cars that attempted to qualify for the 12.90 bracket, three broke out (went under the index), so they granted me the third place trophy for showing up first round for a single (they should have given the low qualifier a bye-run and had the 2nd and 3rd place qualifiers race for the chance to face the low qualifier in the final . . . but they didn't). I still do not have a good dial-in set-up for the 13, 12.90, or 12.50 brackets. Oh well. My 11.90 set-up is looking better every eek . . . as I get to know the car better and have more data. It has been fun to drive the car.
     
  2. DEE

    DEE New Member VIP Racer

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    Hi DR.Jeff

    I'm in BKK right now , that's my pleasure
    my cell 0865556999

    D
     
  3. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    So, I was at the track again last Saturday night . . . still gathering data from three runs that night. Khun Mac and I have sorted all the mechanical details now: the trans controller ECU, engine ECU, and suspension settings are all within a good operational range now. The main issue is how to dial the car for the slower (12.9 and 12.5) brackets. The Familia just wants to go fast . . . . so fast that even waiting for the green light to jump on the gas is still TOO fast for the 12.5 second class! We will have to actually take more power out of the motor by making it run rich (the MicroTech ECU holds several maps) . . . it is already set to run without any boost control -- just the wastegate spring which yields 'only' 0.9 bar . . . . . in addition to shifting at an even lower rpm . . . . . . .

    But . . . . . . during the class qualifying run it went a total time of 12.05 after waiting forever at the starting line . . . . . . . . way too fast. The most amazing thing about that number was that even with only 0.9 bar, it ran an actual e.t. of 10.90! 10s at under one bar! Amazing.
     
  4. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    Attached is a lo-res movie of that 10.90 run on 0.9 bar boost. The slow leave off the line was because we were trying to qualify for the 12.50 (total time) bracket.
     
  5. amiyama

    amiyama Member Privilege

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    Haha....Dr.Harpers...keep it all up. And see you at the pit this Sat.

    and for the 23rd, I finally gonna see Richard's car!
     
  6. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    Amiyama. I won't be at this track this week-end or next. I will be there on August 23 for the "King of Truck" race. See you then! I do not think Richard's truck will be there this week-end either . . . he is waiting for the wiring guy to do his job (forever!).
     
  7. pornnirun

    pornnirun New Member Member

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  8. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    YouTube movie. Go here and comment please.


    [media]http://www.youtube.com/watch?v=FFItBqDtXC0[/media]
     
  9. TEUY

    TEUY New Member Member

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  10. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    Thank you Race Truck Magazine for putting on a very good race. My crew and I had a great time. Congratulations to the winners as well. My little bracket truck did very well. I still need to sort out some equipment so I can get the car up on the stall speed of the torque converter at the starting line, but I'm not complaining. The little bracket Familia ran an all-time best of a 10.63 on a very slippery track at only 1.2 bar with NO NOS! See you next time!
     
  11. RA 720

    RA 720 Well-Known Member Member

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    เวลาดีนะครับ ขอให้ดีกว่านี้อีก ออกตัวอย่างโหด
     
  12. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    RA 720 . . . Thanks for the photos. Next time you are at the track please come over to my pit and say Sawadi Krup.
     
  13. benzene

    benzene New Member VIP

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    now that's ...... a RACE TRUCK :D:D:D
    lovin' it.

    3 thumbs up for HARPER RACING !!
     
  14. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    Well . . . with Mad Mac (Mactec) driving, we had our first win last Saturday night in the 'Pro Bracket 11.90' class. Mac did an excellent job of driving and the race car responded to all our tuning as it should. I feel we are 90% back to a set-up that will be consistent and reliable for multiple bracket classes. Like any bracket race, there is always an element of luck involved: you can only tune to within about .07 second because of the normal variation in human reaction times . . . . so winning the final round by only .04 (our 11.85 to the losing 11.81) falls within that variation . . . and is therefore luck. Next time it can go the other way. However, if a car can regularly run within that .07, you will win a lot.
     
  15. Reloaded

    Reloaded New Member Member

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    Sawadi Krup
     
  16. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    Sawadi Krup to you too, Reloaded.
     
  17. benzene

    benzene New Member VIP

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    :):) congrats....and really liked how you detailed it down to .07 sec khob khun krub :D
     
  18. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    Update

    Two weeks ago I blew the head gasket at the # 1 cylinder. The 3JZ has higher compression than a 2JZ and, combined with a poor header design, caused too much cylinder pressure in that cylinder. So, I had a new, bigger, longer, and better made. I also adjusted the camshaft overlap to take out a little cylinder pressure as well. I took it to the race track last night (21/11/08) to see how it would run.

    Last night was a great testing session. I am really pleased with
    my racer's performance. Before we went to the line for the first run
    I told Mac that he would run a (total) et of 11.95. He ran an 11.98
    total! On that run he launched at 2300 against the 2-step limiter,
    shifted at 5000, and ran 0.9 bar of boost and ran an actual 10.91 with
    an amazing 1.71 60-foot time. Amazing because of the low launch rpm.

    That's about as perfect a launch as you want a bracket racer to be --
    quick with no tire spin -- so very repeatable and consistent. The new
    header and waste gate arrangement seems to be working . . . the
    sound is different (deeper) . . . it sounds "freed-up" . . . and
    breathing better. Tonight we race.
     
  19. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    It has been a long wait for the rebuilding and updating of the Bangkok Drag Avenue facility. The changes are very welcome from a racers' point of view: better safety. However, the owners are struggling with making the surface sticky enough for the 6-second capable rail dragsters now in Bangkok -- or my mid-10-second bracket truck. I was at the opener a few weeks ago and, because of uneven patches of rubber on the track, broke the rear gears. I have since replaced them. Khun Mac tried to make a test run last week, but there was NO TRACTION to be found. I am waiting for more cars to go down the race track to deposit more rubber before I try again.
     
  20. peanut

    peanut New Member Member

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    Please keep update the progress, very enjoy following the progress of the car and good luck this year
    :)
     
  21. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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  22. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    Bye-Bye 3JZ!
     
    แก้ไขล่าสุดโดยผู้ดูแล: 14 สิงหาคม 2009
  23. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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  24. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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  25. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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  26. ปูเป้คุง

    ปูเป้คุง Active Member VIP

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    Hj Dr. jeff Harper
    Good Good Good
     
  27. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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  28. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    More progress: the brackets for mounting the Vortec supercharger have been mocked-up in advance of fitting all the components. See my racing projects web page for more detail.
     
    แก้ไขล่าสุดโดยผู้ดูแล: 20 ตุลาคม 2009
  29. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    More progress: the supercharger is mounted and the crankshaft pulley has been mounted to the ATI balancer. The injectors are mounted in new fuel rails. Headers are next. It is getting very close to being done now . . . in time for the big races coming up.
     
  30. Dr. Jeff Harper

    Dr. Jeff Harper New Member Racer

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    More Progress: A little BLING doesn't make a race car any faster . . . you just like looking at it more (if that is possible!). My Familia is now at the header shop having a set of stepped headers made with merge collectors. The primary tubes will be [are suppose to be] equal length (and somewhat short), with the first 50% of the length at 1 5/8", and the second 50% of the length 'stepped up' to 1 3/4", then into the merge collectors. This is current header theory for drag cars with open exhaust (no mufflers or tail pipes). The idea is to keep the speed of the exhaust gasses as fast as possible. As the gasses meet the step up in size it expands, causing a 'negative pressure wave' to travel back up the pipe toward the cylinder head. The same thing happens when the exhaust arrives at the merge collector. The combination of these compounded negative pressure waves increases the speed which creates a greater ability to 'evacuate' the combustion chamber which allows more intake charge to enter; therefore, the horsepower. Claims of 20-30 horsepower over traditional headers are common.
     
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