My I35 falls on its face when it hits 2nd gear

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cory2081
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Joined: Sat Aug 16, 2003 9:53 pm
Car: '07 350Z
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Just curious if there are any mods to help out with this problem. It seems like the car just falls way below its torque curve when it gets into 2nd gear at full throttle. Of course, it starts to pull hard after a second, but, it's kind of annoying. 1st gear feels great, torque on demand. I wonder if it's something in the cam timing programmed in by Nissan to limit the torque when the car shifts to second?? Anyone else notice this?


Q45tech
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Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl

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Modern cars use torque control to increase reliability of transmission.The TCU signals ECU to reduce ignition advance to near zero just before shift, during shift, and ramps back up after the shift.

Use a Consult to monitor ignition advance vs rpm vs speed etc to see this effect in 0.03 second increments...............maybe it is taking longer than the 1.0 sec normal time?

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cory2081
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Joined: Sat Aug 16, 2003 9:53 pm
Car: '07 350Z
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I figured it had to be programming. Is there anyway to change these settings?? I really wish there were aftermarket flash programmers for our cars


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