Re: Gen info on crown vic
Your 2000 CV with single exhaust will have about 190 horsepower (210 or so with dual exhaust).
The axle ratio can be found by looking at the sticker on the driver's door. There should be a section of the sticker that says "AX". Underneath that you'll see either a letter or a number that can be translated into the rear axle ratio, as well as telling you whether it's an open differential or a limited slip. Unfortunately I don't know the codes for the newer style cars, but I'm sure it's floating around the net somewhere, so you should be able to figure that part out.
For dual exhaust, depending on what your budget is, you can do stock factory dual exhaust, or upgrade to a better system (I'm not sure if there's aftermarket stuff for the newer cars or not; I'm more of a "box" style guy). The factory duals would be easiest, all you'd have to do is get an H-pipe, another muffler, and a tailpipe for the other side of the car. The H will bolt directly to your factory downpipes, and you should find that the hangers are there on the other side for the other tailpipe.
Any more questions, feel free to ask!
1989 Ford Crown Victoria Police Interceptor
2bbl Carbureted 351W V8, ported and polished E7TE heads, Edelbrock cam
AOD Transmission with B&M Shift Kit
3.55:1 Positraction Rear Axle
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