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View Full Version : shift point, and power band?


ososlow99svt
08-09-2005, 09:45 PM
i was wondering, at what rpm do you shift at? i have a 99 cobra with slight mods: k&n filter, bbk off road x-pipe, 40 series muflers, a tremec 3650 trans, and 4:10 gears. i've been playing around with different points but the ol' ass dyno isnt quite accurate. does the powerband continue all the way up to redline on these cars? thanks in advance for your replies.:fordflag:

tcrews
08-10-2005, 08:48 PM
The power band doesn't continue to redline, in usually starts dropping around 6,000rpm or so. The main thing to remember is that you don't shift out of gear because you've reached the "peak" power point, you shift at an rpm that keeps you IN the powerband of the next gear. The best shift points based of the T-45 tranny (T3650 included) is about..

1st > 2nd 7200 rpm (you'll hit fuel cut off so just shift around 7,000)
2nd > 3rd 6900 rpm
3rd > 4th 6800 rpm

The spacing in gear ratios of the transmission is the reason the rpm varies. You want to make sure when you shift your rpms fall into part of your powerband and not below it...ie from 6,000 - 7,000 rpm (when your power is dropping) in 1st gear you are still making more power than if you shifted to 2nd gear from 1st @ 6,000 when you hit your peak. Reaching high up in the rpm band and then shifting to the next gear allows your rpms to drop right into your powerband and will keep accelerating your car the quickest.