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Old 04-28-2013, 05:42 AM   #8
Hawk77FT
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For all of you who want the dip gone here is an explanation from someone who knows a thing or two about tuning/engines:

"As posted somewhere previously, the “torque dip” is a result of engine internal design not tuning. The only thing tuning can do is move the dip somewhere else.


There’s a long discussion here, but the best way to think of it is to look at the torque curve… if you permit me some artistic license, the torque curve looks like two hills with a valley at either end and another in the center. Each of the hills is a cam profile… low speed on the left and high speed on the right. The peak of each hill is the maximum breathing that cam can provide… either side of the peak the cam doesn’t breath as well and that will only change by re-profiling the cam's lift and/or duration - you can only change the hill shape by re-profiling the cam. Changing the VVTi timing just moves the peak left or right... the problem is if you move, for example, the high speed peak left to fill in the valley between the two peaks, the valley to the right of the high speed peak gets deeper very quickly and the engine falls on it's face."

Therefore, there is no tune out there that removes the dip..yes it might either reduce it or move it elsewhere, but you cant completely remove it without upgrading the cams. I am sure that in the following months/years we will see some modified cams ready to go for our cars, but until then we will have to deal with it.
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