I own a 1992 Ford Crown Victoria sedan with a fuel injected 4.6 liter V8 engine and stock dual exhaust. It has 210 net horsepower, and it gets 15 mpg in the city. What modifications could be made to this vehicle to make it faster, more powerful, and more fuel efficient? I am willing to spend up to $2,000. Any advice is greatly appreciated. Thanks
For openers, you could rebuild the engine. I assume that the engine has well over 100,000 miles on it, and the rings and valves aren’t sealing as well as they could. You might be able to find a longer duration cam and/or an intake manifold to add while you’re in there.
Alternately, you could put in a bigger engine. Crown Victorias came with the 5.0 liter engine, and there is seemingly no limit to the aftermarket stuff available for the 5.0.
Drop it off a cliff. Fast, you bet. Powerful, well, gravity sucks! And absolutely fuel efficient - no fuel used at all!
More seriously, if you want more powerful and more fuel efficient and only spent $2000, the only way you’ll find it is to make sure the engine, brakes and suspension are in top condition. Beyond that, you are into lots of money and lots of compromises (power and efficient don’t generally mix).
I would suggest you go out and buy a few books or magazines on modifying the Mustang GT. You engine is essentially a Mustang 4.6 liter V-8. There are probably many things you can do with $2000 if you do your own work. However, that money will evaporate very quickly if you pay someone else to do it.
You might look at the cost of trading your engine in on a late model, used Mustang engine. $2K might do it. Recent 4.6 L GTs will have 250 to 275 HP and and a Cobra (good luck finding one at a decent price) would have over 300 HP. A fully built up and supercharged 4.6 could approach 400 HP and still be street driveable but I don’t think you want to spend that kind of money.
More powerful and more fuel efficient rarely go hand in hand. You usually have to give up one for the other.
The best bang for the buck in performance mods is forced induction. Superchargers (“blowers”) ought to be readily available for that engine, and can add significant gains. More power can be had by adding a turbocharger, but they are more complex, more maintenance-needy, and generally less reliable.
Remove the governor and catalytic converter if it’s legal to do so where you drive.
a K and N filter would give you the most bang for the buck on a engine that big. They claim a 10-20 bhp increase. http://knfilters.com/kits.htm
I don’t know much about the '92 Crown Victoria, but you should be able to do exhaust (catback; and I’d go with a high flow cat, rather than just remove it completely), intake, gears.
If it is an automatic you can always get an aftermarket torque converter. I’ve heard that Ford’s don’t make the best automatics and that TC will wake it up.
As far as gas, the catback and intake shouldn’t hurt-I think they simply FREE up horsepower than really ADD. But the gears and other mods probably will lower it some.
As they say, speed costs money. How fast do you want to go?
$2000 does not buy a lot of speed.
I don’t think there is a physical governor on these cars - it is part of the ECU. The only way to remove that restriction is to get a new chip (although police crown vic’s are apparently programmed without a “governor”). However, removing the “governor” will not make the car more powerful, just get rid of an articifical limit.
Don’t be a dick and remove the catalytic converter. It’s there for a good reason, and with modern 3-way catalytic converters (like on the crown vic) its effect on performance is either minimal or nil. If it is causing performance problems, it’s clogged - replace it. Also, removing a catalytic converter is illegal everywhere in the US.
Engineering involves compromises - you pick up some desireable attributes, you lose a bit in some other desireable attributes. Choices like camshafts, rear end gears, suspension components, etc all fall in this category. Ford Engineers have to pick what is “best” for the millions of customers that will be buying this vehicle, but those choices might not be best for you. You can change these things yourself to tilt the compromises more towards your own wants/needs.
However, air filters aren’t one of those compromises. You figure out how much air an engine needs, and you size the air filter and intake plumbing accordingly. I suppose there could be a few cars where the air filter is undersized because they couldn’t figure out how to squeeze a bigger filter in, but I doubt the Crown Vic qualifies.
K&N claims “increase horsepower by as much as 10%”. If this is really true, then car engineers are dolts, because they made their cars less powerful by undersizing the OEM air filter by 10%.
Take it to a mechanic that can do a complete diagnostic check of the car’s “computer” and repair anything that comes up on the printout.
After the headaches subside think about the following;
Undersize pulleys for the waterpump, power steering pump, alternator and crankshaft. A smaller pulley is easier to turn but the trade-off is that it does less work for each turn. The power steering pump will assist less and the alternator will produce less current. The water pump and A/C can be affected. None of this should be a problem on the Vic and it’s relatively cheap.
Cat back exhaust for a few extra horses and a throaty tone. Not to expensive if you avoid fad mufflers and stainless anything.
New “chip” for the “computer” that will adjust the fuel mixture, timing and maybe even the transmission. Some advertise more power AND better fuel mileage… YMMV.
Unless you’re looking to sign Victoria up for Nascar, you shouldn’t need more trouble than the above will give you. Good Luck.
Two words. Speed holes. Speed holes make the car go faster. 
Stickers…lots of stickers.
I put a cover on my steering wheel. It’s blue. Will that help?
Be aware though that you’re not going to turn a hulking Crown Vic into a speed demon with $2000. 10-20hp may not even be noticable in a vehicle that weighs that much.
My recommendation would be to not spend that much money on an older Crown Vic, unless you have a special reason for using that vehicle. If you want a performance car, sell the Crown Vic, add in your 2K, and buy something that’s already fast.
And remember - you’ll never get a nickel of that $2000 back on resale.
I put a K & N Filter on my 1991 Thunderbird, and I now get about 4 miles per gallon more than I did before.
I do realize that this could be due to the old air filter being clogged in the first place, but it did not seem very dirty when I took it out.
DON’T put a later model mustang engine in it. You’ll kill the slushbox automatic that Ford was nice enough to put in the CV. It simply isn’t able to handle the load of a powerful engine.
Switch the air filter, put on a new exhaust (not a coffee can, that won’t do anything except make people think you’re an asshole).
Are you sure about this? I’ll admit I don’t keep up on all the latest specs but traditionally Ford only had one basic transmission for V-8 vehicles. There was always a police/high performance version with different bands and better cooling but a Mustang GT wouldn’t necesarily have that. Otherwise the only difference was electronic shift point setting. My guess is that the first added 100 HP or so wouldn’t faze the transmission.
Also, I’ll agree with the earlier comments that I would not expect more than a couple of horsepower from an air filter change. Since this car has factory duals, I also wouldn’t expect too much from any legal exhaust change.
Expressed mathmatically speed is a function of cubic money. How fast can you afford to go? 
You are 100% right that 2K is not much cubic dollars.
My first recomondation costs almost nothing.
A Crown Vic is a heavy battle cuiser. Lbs is the same as horsepower. Put the damn car on a diet.
Lose the spare, back seat, door panels and everything else you can pry off the car. hell if you are serious, change the glass side and rear windows for plexiglass.
As far as money goes, a shift kit for the trans, make sure the engine is in top shape, and you will probably be out of your 2K