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When to Shift

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Old 11-14-2008, 03:07 PM
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Default When to Shift

I have been playing with all different RPMs to shift at in order to stay within my best power band but I just can't decide which is the best on feel alone. Using my dyno sheet as a guide, where can I determine the best shift points to be. Someone suggested that I should shift where the torque and HP curves cross, but that just seems way too low to me. At my max hp, however, my torque has already dropped off significantly so I'm just not sure.
Old 11-14-2008, 05:58 PM
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If you have the stock T56 Gear Ratios, when you shift into your next Gear, it'll bring you back down into higher RPM's than where you started with the previous Gear. Look at a Gear/MPH Chart (http://www.f-body.org/gears/) and you will understand what I mean.

I shift mine at 6500, pretty much where the HP curve starts to drop, and it brings me back down to right about my Torque curve, and a little more after it with each shift.
Old 11-14-2008, 10:32 PM
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when you feel the car stop pulling, shift. I agree that shifting where the curves cross is wayyy too low. Best way to find out is to go to a track and see what gives you the best times.
Old 11-14-2008, 10:37 PM
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Post up a dyno graph, it'll probably help get better quality answers. You definitely want to shift at at least your peak hp, if not higher. I've heard that sometimes you want to spin higher than peak hp (for a higher average hp? I think?), but it really depends on the situation, curves, and other stuff.

I'm not the one to ask, just putting ideas out there. For sure post a dyno though, it'll help other people more knowledgeable than me help you out.
Old 11-15-2008, 08:04 AM
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There is 2 theories on this.

1. shift when you feel the car starting to nose over.

2. shift right when your HP starts to drop after it peaks.


Those two theories are almost the same thing. Post a dyno graph and that will help us make an estimate where you should shift.
Old 11-15-2008, 11:22 AM
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Here is my dyno sheet off spray.


And here is one with the gas.
Old 11-17-2008, 11:44 AM
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to the top
Old 11-18-2008, 11:09 PM
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Anyone got any more input on this?
Old 11-19-2008, 06:25 AM
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65-6600rpm shift.
Old 11-21-2008, 12:46 AM
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Originally Posted by melchoir
65-6600rpm shift.
Agreed, I use a shift light play with the setting's & see how it affects my times.
Old 11-21-2008, 04:30 AM
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^^Depends on how high his powerband is.

I shift at 6500 cause that is the ideal RPM for me, but not everyone is going to be the same..



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