Thread: When to shift?
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Old 04-23-2017, 11:33 AM
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Stan Weiss Stan Weiss is offline
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Quote:
Originally Posted by PontGuy View Post
Remember HP is not a function of gear ratio so calculating it like you are doing is not correct. Hence the 700+ HP numbers which are way more than your engine makes. Just read the HP right off the dyno chart. So for 1-2 your car will be making 320 HP at a 5300 RPM shift which matches nicely with the 320 HP at 3950 after the shift. And so on for the other shift points. Doing it this way is a lot easier than calculating wheel torque and you end up with the same results.

The curves in your dyno chart are very flat which would mean that the shift points should not be that critical at the track. But then again with carb/fuel flow issues resolved the curves may look a lot different. And real world never works out quite like theoretical due to other factors in play.
X1000

I do not know anything about Adam's car or setup but playing with a computer simulated run shifting at 5300 5200 5200 and saying that this is the best then 5000 5000 5000 and 5500 5500 5500 are both only about .03 worse. You would be much better off working on getting good 60 foot times than playing with getting the perfect shift rpm.

Stan

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