I dont think a 5.7 will do 160. I had an 07 RT for a patrol car and the highest I ever had it was 147 ish. The new ones MIGHT do 150-155 but I dont see 160 especially with all the extra weight of the cage and equipment.
Weight has very little to do with top speed. It effects acceleration, most definitely, but not top speed. Aerodynamics or lack of it, is what really kills the Chargers top speed.
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