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Thread: [ZR1 No-lift shift] - can this feature be added to an E38 computer?

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    Advanced Tuner Justinjor's Avatar
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    [ZR1 No-lift shift] - can this feature be added to an E38 computer?

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    I have a 2008 LS3 and I frequent the dragstrip quite a bit and was interested to learn if I could add the same no-lift shift feature as found on the ZR1. Is it something that can be tweaked in the tune or is that a feature specific to the ZR1s computer?

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    Senior Tuner 5_Liter_Eater's Avatar
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    All you need to do is set the park/neutral rev limiter to just above the RPM you would drop to during a shift. You kind of need to move your clutch inhibit switch down because otherwise AS SOON as you touch the clutch it kicks in.
    Bill Winters

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    Advanced Tuner Justinjor's Avatar
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    At the risk of sounding totally ignorant, what is the clutch inhibit switch? Is that the physical switch on the pedal that lets the computer know the clutch is pushed in? Or is that something in the tune itself?

    Also, wouldn't setting the park/neutral rev limiter at say, 5000, prevent me from launching the car at 6000+ like I normally do? Is there another way to do it?

    What if I set the park neutral rev limit to 6500, I wonder if that would accomplish the same thing?

    Lastly, the motor drops to a different rpm on each shift so how would that work?

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    Senior Tuner 5_Liter_Eater's Avatar
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    Jez I didn't think about anyone launching at 6 grand. In that case I would set the P/N limiter to whatever RPM you want to launch at and kill two birds with one stone. I just came up with the "a little over what the RPM drops to". ~1k lower than redline seems like a good start.

    Yes the inhibitor switch is the physical switch that lets the car know the clutch is in and it typically trips as soon as the pedal is pushed.
    Bill Winters

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  5. #5
    Advanced Tuner Justinjor's Avatar
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    Thanks for the info Bill.

    Ya, I routinely launch it at 6000-6500 to get my 1.5 or better 60fts with my stock clutch and stock rear.

    Here is a video if you're interested

    http://www.youtube.com/watch?v=KxNb06fGTV4

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    Senior Tuner 5_Liter_Eater's Avatar
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    Bill Winters

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    Senior Tuner IDRIVEAG8GT's Avatar
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    Holy fuck dude. Can I come run at that track?!

    Nice driving by the way.
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  8. #8
    Senior Tuner 5_Liter_Eater's Avatar
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    I can't believe the stock clutch doesn't just give up the ghost. Mine would "pedal to the floor" like s son'beach.
    Bill Winters

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    Advanced Tuner Justinjor's Avatar
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    Haha, sure. Its just Palm Beach International Raceway. It was the first of the 2012 American Muscle Car Challenge series that Horsepower Sales sponsors.

    Thanks for the compliment

    Also, Bill, I set the p/n rev limiter to 4500 to try it out last night but it felt weird. Instead of acting like a 2-step persay it was lazy and undulating- does that make sense? I'm not sure if I'm describing that correctly but is there a way to make it more peppy and responsive?

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    Advanced Tuner Justinjor's Avatar
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    Oh I've killed the stock clutch about 10 or 12 times, but it always comes back to life once it cools down and I drive it for a few minutes.

    What you can't see on that video, or other videos from that day, is me reaching down with my left foot and pulling the pedal back up to the top between the 2-3 and 3-4 shift. It makes for an interesting quarter mile pass to say the least.

    New gears(4.10s) and new clutch goes in next month.

  11. #11
    Senior Tuner 5_Liter_Eater's Avatar
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    OK that makes sense. Mine would always pedal to the floor 2-3 and 3-4. Thats a fantastic run given the fancy footwork required.

    RE Lazy rev limiter: Look at what method(s) it's using. If it's using ETC then it will be a dog. Use only fuel and/or spark. Also, disable CFCO so it doesn't cut out entirely with the clutch in. Can't remember if you're spraying meth or not. If so be careful with the limiters. IE: only killing fuel and leaving spark in.
    Bill Winters

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    Advanced Tuner Justinjor's Avatar
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    Thanks Bill. I only looked at it briefly but I'll revisit tonight and make sure the settings are correct.

    No meth here. Just air and fuel.

    So I need to disable the option for it to cut the throttle and force it to use fuel and/or spark, and cutting fuel is preferred?

  13. #13
    Senior Tuner 5_Liter_Eater's Avatar
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    If you're not spraying meth then take your pick on fuel and/or spark. But the ETC method kills it.
    Bill Winters

    Former owner/builder/tuner of the FarmVette
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    Advanced Tuner Justinjor's Avatar
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    I assume if I cut spark, that could send unburnt fuel out the tailpipe, resulting in fireballs, right? I don't really want that so cutting fuel sounds better.

  15. #15
    Senior Tuner 5_Liter_Eater's Avatar
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    Y U NO WANT FIREBALL?

    Bill Winters

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    Advanced Tuner Justinjor's Avatar
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    Lol, fireball looks cool for sure. I feel like it might break the exhaust or something, I don't know.

  17. #17
    Senior Tuner IDRIVEAG8GT's Avatar
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    Quote Originally Posted by Justinjor View Post
    Lol, fireball looks cool for sure. I feel like it might break the exhaust or something, I don't know.
    With nice exhaust and preferably no cats you can fireball all you want IMO. Hell, I made a fake 2-step for Neutral in Auto cars and the blow flames like mad.
    Gray Ghost- The abomination. 2007 Chevrolet Silverado CCSB. 98mm turbo, nitrous, 428LSX, Rossler 80E with a brake. Finally finished. 23 psi, no numbers, Slow as hell.

    PBM G8- Aluminum 364, twin Precision 67/66 turbos, 6L90 trans swap, CTS-V/Vaporworx fuel system, slowly making progress.

    Dads 2011 CTS-V- Stock bottom end, stock heads, LS9 cam, pullies, ported blower, ported TB, D3 goodies, and lots of nitrous.
    618/618 motor
    906/862 spray

    Caterpillar 50 Forklift- Duramax swap

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    Advanced Tuner Justinjor's Avatar
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    Really? I don't have any cats. . .

    So how do I make fireballs? Have the computer cut spark instead of fuel for the limiter??

    Set the p/n to 4000 and let her rip? :O

  19. #19
    Senior Tuner IDRIVEAG8GT's Avatar
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    Quote Originally Posted by Justinjor View Post
    Really? I don't have any cats. . .

    So how do I make fireballs? Have the computer cut spark instead of fuel for the limiter??

    Set the p/n to 4000 and let her rip? :O
    Exactly! Remember, exhaust has to be hot though or else you won't get the flame effect, it's the hot pipes which ignite the unburnt fuel.

    Might wanna make sure the clamps on your mufflers are tight as well so they don't get blown off lol.
    Gray Ghost- The abomination. 2007 Chevrolet Silverado CCSB. 98mm turbo, nitrous, 428LSX, Rossler 80E with a brake. Finally finished. 23 psi, no numbers, Slow as hell.

    PBM G8- Aluminum 364, twin Precision 67/66 turbos, 6L90 trans swap, CTS-V/Vaporworx fuel system, slowly making progress.

    Dads 2011 CTS-V- Stock bottom end, stock heads, LS9 cam, pullies, ported blower, ported TB, D3 goodies, and lots of nitrous.
    618/618 motor
    906/862 spray

    Caterpillar 50 Forklift- Duramax swap

  20. #20
    Advanced Tuner Justinjor's Avatar
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    Brb, testing it out. . .


    Thanks for all the tips everyone. I appreciate it