Thanks for the additional information. I ran the numbers and came up with a rear gear ratio range in the 4.30 - 4.88 range for your combination. If you're looking to make a change then I would split the difference and install a 4.56 ratio. The increase in gear ratio is actually going to improve your converter efficiency, so I would make a ratio change before making any adjustments to the converter. A 4.56 ratio should net you right around 7,000 - 7,200 RPM through the 1/4 mile traps.