auto or manual
But, about the most you will get out of a 4L60E is in the 650 range. It was designed to take 385 lbft torque from day one. That being said, we have guys in the mid to low 10.xx's with them. I know of several in the 9.xx's.
I would suggest that it really is combination specific, meaning that you need to decide what your short term and long term goals are and then build for that mindset.
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