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Where to shift

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Old 04-15-2007, 08:01 PM
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Default Where to shift

My car is an automatic but I have to manually shift it to make it rev above 4,000 RPM( I know it's not normal but lets not discuss this.). Peak hp is at 5,3000 and peak torque is at 4,400.
Where would you guys shift to get the best time? The dyno graph only goes up to 5600 and seems to drop at 5,500( but this coudl be when he let of the gas).
Old 04-15-2007, 08:23 PM
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Just keep it in D.

Your car might make peak torque and power before 6k, but that is where your car will shift into the next gear. Manual guys don't shift at the peak tq or peak hp either. Would you rather make 350hp and be in 2nd gear (1.62 ratio) or make 325hp and be in first(3.06 ratio)?

Bottom line: just keep it in D and let the car shift for you.
Old 04-15-2007, 11:00 PM
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.

Just what I was taught many many years ago, and it was for real drag only cars.
I was always told to start @ 1000 over peak HP, and tweak it from there.
No help on a modern car that still shifts, good luck.

.
Old 04-16-2007, 09:34 AM
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I would keep it in drive but then the car will only rev up to 3,000 and stay there until it decides to shift, so I have to shift it manually to even get to my peak power. The tranny has some kinda street/strip valve body. Where it will shift if put in D but for racng it has to be done manually.
Old 04-16-2007, 09:57 AM
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I leave it in D and let it shift itself. I also tune the shift points with a Diablo tuner. It takes time for it to shift so you have to tune it over the peak hp point. I had it set for 6200 for a while then went down to 6000. I seem to get the best time about there.
Old 04-16-2007, 11:09 AM
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Mine is set about 5800-6000 depending on whether I'm spraying or not.

Derek




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