Thread: actual shifts are alot higher than commanded, why?

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  1. #1 actual shifts are alot higher than commanded, why? 
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    Keep forgetting to post this lil issue, but for the time being my shift point for 1st gear is at 6100 and 2nd gear is at 6000. I did a few runs from a dig and scanned(scanned with 3.3" pulley btw). What I noticed was the car is actually shifting at approximately 6350 in 1st and a bit over 6000 in 2nd gear. What could it be or should I just lower the 1st gear shift point to 5900?
    old setup-Z7 Turbo Kit w/T66, A2A I/C, stock cam & valvetrain/LS1 MAF/Ported 99TB/PowrTuner/AFC/Devils Own/LS1M Scanner/PRJ FP/42# Injs=12.3@118mph street tires -
    (Sold)BACK TO M90 Vs cam w/3.5" pulley/meth/25* timing+bolt-ons
    01 Z28 A4 HP-self-tuned, LTs, FTRA, 3600stall 12.3@112mph
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  2. #2 Re: actual shifts are alot higher than commanded, why? 
    GTP Level Member Smokin2000gtp's Avatar
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    This is because it takes time to shift. It starts to shift at the commanded RPM, but doesn't actually complete the shift till a little bit later, hence the higher RPM. Just lower the shift points till it actually shifts where you want it.
    2000 Silvermist Grand Prix GTP Coupe

    Mods-Custom Thrasher CAI|Ceramic Coated S&S Headers|3.4" pulley|ZZP S4 Blower|Powrtuner|PRJ 10.4mm wires|HIDs|F-Body brakes|Koni's and Voglant's|
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  3. #3 Re: actual shifts are alot higher than commanded, why? 
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    i guess, i didnt know it would shift over that much. i would of thought maybe at around 6200, but i did notice it was shifting also around 6400 as well. i guess i'll lower the shift point for 1st gear then. i just dont wanna fubar anything with that hi an RPM even though im running 105# springs and the vs cam. thanks smokey
    old setup-Z7 Turbo Kit w/T66, A2A I/C, stock cam & valvetrain/LS1 MAF/Ported 99TB/PowrTuner/AFC/Devils Own/LS1M Scanner/PRJ FP/42# Injs=12.3@118mph street tires -
    (Sold)BACK TO M90 Vs cam w/3.5" pulley/meth/25* timing+bolt-ons
    01 Z28 A4 HP-self-tuned, LTs, FTRA, 3600stall 12.3@112mph
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  4. #4 Re: actual shifts are alot higher than commanded, why? 
    GTP Level Member Smokin2000gtp's Avatar
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    Maybe try and lower the shift times and raise the shift line pressure too, hopefully that will help you out some.
    2000 Silvermist Grand Prix GTP Coupe

    Mods-Custom Thrasher CAI|Ceramic Coated S&S Headers|3.4" pulley|ZZP S4 Blower|Powrtuner|PRJ 10.4mm wires|HIDs|F-Body brakes|Koni's and Voglant's|
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  5. #5 Re: actual shifts are alot higher than commanded, why? 
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    will, whats the adviseable actual shift point to shift with the vs cam? ~6200RPMs?
    old setup-Z7 Turbo Kit w/T66, A2A I/C, stock cam & valvetrain/LS1 MAF/Ported 99TB/PowrTuner/AFC/Devils Own/LS1M Scanner/PRJ FP/42# Injs=12.3@118mph street tires -
    (Sold)BACK TO M90 Vs cam w/3.5" pulley/meth/25* timing+bolt-ons
    01 Z28 A4 HP-self-tuned, LTs, FTRA, 3600stall 12.3@112mph
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  6. #6 Re: actual shifts are alot higher than commanded, why? 
    GTP Level Member Smokin2000gtp's Avatar
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    I'm not really sure what the shift points should be with a VS cam, but I would think that 6100-6200 would be fine. Maybe someone else will chime in about it.
    2000 Silvermist Grand Prix GTP Coupe

    Mods-Custom Thrasher CAI|Ceramic Coated S&S Headers|3.4" pulley|ZZP S4 Blower|Powrtuner|PRJ 10.4mm wires|HIDs|F-Body brakes|Koni's and Voglant's|
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  7. #7 Re: actual shifts are alot higher than commanded, why? 
    TDCRacing
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    As far as the shift points I wouldnt go over 6000 with it. Not that it will probably hurt anything but the cam's not designed for high rpm's....As far as your transmission goes they can take anywhere from 200 to 1000 rpm's to shift from where they are set at in the pcm. Depends on what kind of condition your tranny is in. Before i got the new on i had to set the shift points at like 5000 and then at the track it would still hit the rev limiter before it would actually shift into second because it was slipping so bad.
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  8. #8 Re: actual shifts are alot higher than commanded, why? 
    TDCRacing
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    Also you can try messing with shift firmness and shift time...you'll notice a big difference if you set the shift the shift time tables to around 0.06
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  9. #9 Re: actual shifts are alot higher than commanded, why? 
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    Quote Originally Posted by fst View Post
    Keep forgetting to post this lil issue, but for the time being my shift point for 1st gear is at 6100 and 2nd gear is at 6000. I did a few runs from a dig and scanned(scanned with 3.3" pulley btw). What I noticed was the car is actually shifting at approximately 6350 in 1st and a bit over 6000 in 2nd gear. What could it be or should I just lower the 1st gear shift point to 5900?
    First zero out your speed table. The computer takes from both, so it will take the higher number. If those are zeroed out, it's doing that because it will start the shift at the point you command it but it takes a few 100 rpm in first, and 100 or so in second. The rule of thumb is if you want it to shift at 6100 in first command 5900 maybe even 5800 you'll have to give it a try, and second command 5900 and it should work for you.
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  10. #10 Re: actual shifts are alot higher than commanded, why? 
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    ok, i lowered 1st to 5850 and 2nd at 5900. i heard mixed feelings on zeroing the speed table, cant remember what, but ran across it a while back. currently the shift pressures near the bottom of the table(DHP PT that is) is set at 96PSI which is the highest set value. the shift time is also set at i think 0.01
    old setup-Z7 Turbo Kit w/T66, A2A I/C, stock cam & valvetrain/LS1 MAF/Ported 99TB/PowrTuner/AFC/Devils Own/LS1M Scanner/PRJ FP/42# Injs=12.3@118mph street tires -
    (Sold)BACK TO M90 Vs cam w/3.5" pulley/meth/25* timing+bolt-ons
    01 Z28 A4 HP-self-tuned, LTs, FTRA, 3600stall 12.3@112mph
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