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  1. #1
    Non-member StuHERTS's Avatar
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    Gear Change, quickest time

    Hi all,
    Ok,
    im no rally driver but wondered as to when you changed gear.

    I ask this question because my dump valve seems to take a second to "whoosh",
    I find i hold the clutch down and stay off the gas untill the whoosh has gone..
    Is it bad for the turbo to just change up quick or should you release all excess air?

    I don't watch the clock but my passenger just said he see my in car boost clock go to 22psi at gear change.

    Once im up n running im going to hit santa pod to get a time, hoping for about 14 secs?

  2. #2
    Non-member Nottswoody's Avatar
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    Re: Gear Change, quickest time

    From very recent experience stuart it depends on your engine spec bud I ran it at 22psi and could only manage 15.2 bud and I was giving all the beans it had and that's on a t25 tomcat turbo but standard engine upto about 6.5 revs.. Hence the reason I'm building a new engine with a ep Motorsport cam.. Don't set yourself a target just go to see what you get and plan from there bud. Have you got an AFR gauge? I know you've been having probs with the group A carb of yours and I wouldn't be slamming 22psi through it unless you know your fueling is correct or otherwise you will pop that engine bud..

  3. #3
    Motech Tony Walker's Avatar
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    Re: Gear Change, quickest time

    Don't worry about changing gear, ram them home as fast as you can :-) with or without a dv they barely make any difference, just a noise difference really. If your accelerating at wot at 22psi, fueling needs to be spot on along with listening for detonation.

  4. #4
    Non-member Markey Mark (BD)'s Avatar
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    Re: Gear Change, quickest time

    Your engine spec will determine what sort of times you should be going for but in end it all comes dow to how you drive

    If your running 22psi i take it its some kind or larger hybrid, at that pressure 14's should be easy if the enginesa ll ok and set up well for that pressure

    99% of us on here don't run dv's so wouldn't worry about how quick you change gear, its oly issue when you get it wrong and start cruching gears or missing gears and over reving

  5. #5
    Non-member gttjames's Avatar
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    Re: Gear Change, quickest time

    22psi should be better than 15.2

    This is my 1st ever run on the strip, the car was standard other than a dumpvalve and air filter and i did a 15.2
    http://www.youtube.com/watch?v=rde2_ZUw6i4&feature=plcp

    I then added a englarged downpipe, fmic, and set actuator to 17psi, allthough boost gauge only read 14psi and at a rtoc pod day i managed a 14.0 at 99mph (didnt get that run on vid though but have the slip)
    http://www.youtube.com/watch?v=_oqsJcWjOAM

  6. #6
    Non-member Nottswoody's Avatar
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    Re: Gear Change, quickest time

    Quote Originally Posted by Markey Mark (BD) View Post
    Your engine spec will determine what sort of times you should be going for but in end it all comes dow to how you drive

    If your running 22psi i take it its some kind or larger hybrid, at that pressure 14's should be easy if the enginesa ll ok and set up well for that pressure

    99% of us on here don't run dv's so wouldn't worry about how quick you change gear, its oly issue when you get it wrong and start cruching gears or missing gears and over reving
    I guess I was a bit wet round the ears with my limited runs at pod and I was spinning for a while at the lights with crap tyres but be all and end all I could only get a top of 91mph.. Next year new engine and hopefully better times and Definatley getting some slicks at somepoint..

  7. #7
    Non-member Nottswoody's Avatar
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    Re: Gear Change, quickest time

    My bad I'm running 1.4 bar so that's 20psi but actually as Iv been told I'm taking that from the carb top so only 18psi really? Good news is when Iv built my engine there should be another 5 or 6 psi still to play with... Explains more about my pod day..

  8. #8
    Non-member GTphil's Avatar
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    Re: Gear Change, quickest time

    Your time will mostly be down to how you get the car off the line, your terminal speed is a direct reflection of the power the engine is producing.

    Good or bad launch and you will probably find the terminal will be the the same or very close.

    Have a buchers at this
    https://www.rtoc.org/boards/showthread.php?t=14

  9. #9
    Non-member StuHERTS's Avatar
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    Re: Gear Change, quickest time

    Thanks,
    Ill take that into account! Not entirely sure my boost gauge is that accurate anyway but its defo quicker than my last one which was standard.

  10. #10
    Member Thundercat's Avatar
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    Re: Gear Change, quickest time

    Anyone run the full throttle gear change option as supplied on armtec rev limiters, i use mine on my raider and makes gear changes might explosive and fast.

  11. #11
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    Re: Gear Change, quickest time

    use to back in the day, but be warned they will not do the gearbox any favors

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