My tuned XJR makes 540HP to the wheels. About 620HP at the crank. The only way Jaguar got to 225 MPH is because of all the areo tricks they used. At the Texas mile I saw Hellcats gaining almost 5 mph on the top end by taping the hood lines closed and blocking off the front grill. Anything above 150mph or so is mainly impacted by wind resistance. Even small stuff like removing the windshield wipers and for sure the side mirrors can gain 1-2 mph with no additional power. Lowering the car a couple of inches and preventing air from getting under the car by using spoilers and diffusers is another trick.

But take yours to the track and report back. Always like to see other real world numbers.
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