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7AT Bad upshifts

Old May 9, 2016 | 04:24 PM
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7AT Bad upshifts

When i am using Manual mode on the 7AT transmission and pushing the engine hard, I Try to upshift right at 7000-7500rpm but it sometimes doesn't work at all and keeps revving past 8000rpm. it normally upshifts lightning fast but at High rpm just works terribly for me has anyone else experienced this?
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Old May 9, 2016 | 04:51 PM
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It's probably getting tired of all the abuse! Now, it refuses to cooperate.
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Old May 9, 2016 | 06:24 PM
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From: ATX
It shouldn't rev past 8000...

There is a rev limiter and fuel cut off around 7500-7600...
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Old May 9, 2016 | 06:54 PM
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From: Earths toilet: Houston Texas
Originally Posted by qmantran
It shouldn't rev past 8000...

There is a rev limiter and fuel cut off around 7500-7600...
I think the OP....is trying to shift at or just over 7k..not at 7500 +...the transmission delay is causing him to probably run right into the limiter..
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Old May 9, 2016 | 07:41 PM
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Try shifting right before you get to 7. There's a delay with these cars.
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Old May 9, 2016 | 07:50 PM
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Originally Posted by monytx
Try shifting right before you get to 7. There's a delay with these cars.
This. I hit the paddle at 6700 or so and it shifts right at redline. Any later it bounces off the limiter
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Old May 9, 2016 | 07:55 PM
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https://www.myg37.com/forums/g37-cou...ml#post2921978

Originally Posted by Q8y_drifter
First off, the ACTUAL redline set point is not 7,500, it's 7,600rpm. I know it's a small difference but that's what it actually is according to Nissan/Infiniti.

Second, for the people who drive MT's and are asking why he's going that far, he's not. It's the car. He pushes the pedal, it goes all the way to redline and shifts where it's supposed to shift. He can't control how far it goes past 7,600rpm without manually changing the shift point using a tuning software.

Second, you're not actually hitting anywhere over 8K RPM on the stock rev limiter settings. The needle does go past 8K, yes, but the crank is not actually spinning that fast. Datalog the car and see. The highest my car revved according to the datalogs I did using Cipher software is 7725rpm. From inside the car looked like it was revving all the way to 8K. Most of the time it will dip into the 8K range during the shift. This is normal, every auto G does that.

Nothing is wrong with your car so no need to take it to the dealer or anything.
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Old May 9, 2016 | 08:23 PM
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From: Earths toilet: Houston Texas
^^ OP are you feeling the rev limiter kick in and the car go weak? Or is it just running up to 8k like the above information states with no power loss? Otherwise it sounds normal ...other than the lame delay that we all experience all the time...
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Old May 9, 2016 | 09:26 PM
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There is a delay you have to get used to it and know when to up shift due to the delay. Like everyone says the rev limiter will not allow you to rev past a certain rpm
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Old May 9, 2016 | 11:23 PM
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Originally Posted by G37sGraphite
^^ OP are you feeling the rev limiter kick in and the car go weak? Or is it just running up to 8k like the above information states with no power loss? Otherwise it sounds normal ...other than the lame delay that we all experience all the time...
Yea i guess it is the rev limiter as the car slows down like hell.
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Old May 9, 2016 | 11:32 PM
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Hp starts to plateau at 6500 to 7k as the torque descends around 4500k rpm. IME shifting about 6-6500k keeps the VQ in a pretty good spot, especially if you have intake/exhaust mods.

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Old May 10, 2016 | 02:31 AM
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Yeah, I've seen the tachometer go past 8K but like someone else said this is just visual - in reality the ECU is cutting fuel to preserve the rev limit.
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