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    Vic FAQ

Vic Muscle...this section will be all the cool ways to make your Crown Vics perform & handle like a champ -- all sorts of "how to's" and links to the good stuff. For some quick answers, check the Crown Vic FAQ (frequently asked questions) -- anything you want to change or add (e-mail me) ? If you have the time & money, Kenny Brown will do all the work for you here: http://www.kennybrown.com. Also see Sean Hyland Motorsport or Mark Ray Motorsports.

Click on any of the links below for more info on specific Crown Vic mods:

Rims, Tires & Brakes:

• Rims
  Note -- as of 02/01/2002, i have found that MANY different combos will work all with various details to watch out for or specific backspacing to make --this includes 17" Torque Thrust IIs, Roush Perf 18s, 17" Cobras of many types and many other brands 17" & 18". One of my favorite combos: "18x8 front 255/45/18 and in the rear, 18x9.5 with 275/40/18". This is not an easy mod for the CVs, but there are still quite a few options: first off, the backspacing on the '92& up CVs is a little weird. Right around 4+1/2" or 4+1/4". Check out how Mustang rims look on the Vics with the usual 'stang 5+1/2" or more backspacing. A '94 CV with 15" Mustang rims...a '94 CV with 17" '98 Cobra rims. Not bad, but not exactly perfect. Another option is the Ford 16x7 OEM rims with center caps & lugs. They are on www.tirerack.com for $50 to $55. Not a bad solution: cheap, correct backspacing & accepts 255/50/16s no problem...just get good H-Z rated tires to cut down on sidewall bulge. If you want to get nutty & don't like ANY sidewall bulge...take the rims to a speed shop & have them stretched to 16x8. Check Paul's combo: 16x7's with centercaps -- 225/55/16s front & 255/50/16s rear...Z-rated rubber.

• Tires
  Stock sizes are 215/70/15 or 225/60/16. 245/50/17 will also fit perfectly with no speedo error...255/50/16 is also very close as well as 225/55/16. Check this neat Tire Calculator to check speedo & odometer against your stock tires dimentions - basically a 26.65" tall tire. For the actual tires here are my recommendations *this* week: Michelin, Dunlop, Kumho & BFG. Nittos look good too, but not much for recommendations here...

• Brakes
  THE ULTIMATE (medium-buck) BRAKE CONVERSION: Are you getting freakin' SICK_AND_TIRED of your stock '92 thru '97 wimpy 10.8" rotors warping every 15,000 miles after stopping your 4,000 car umpteen times ?? How about a 12.4" rotor & dual piston caliper swap right from factory parts ? Here is the deal (in "Nascar" Mike's words, he has a '96): 
  "I am glad to say that everything swapped over perfectly except for the brake lines. The 99 CV lines are about 3 inches longer, so I had to make new braided stainless steel brakelines. Here is a list of the parts you will need if you do the swap on you 93-97 Crown Vic/Grand Marquis.
  

  • F8VZ-2B120-AA Dual Piston Caliper $77.17 each 
  • F8VZ-2C396-BA Caliper bracket $40.97 each 
  • N801052-S100 Banjo bolt $3.32 
  • Raybestos 66744 12.4" Rotor $47.20 (from CarParts.com with 33% off coupon) 
  • Braided stainless steel lines - 16" long with flared adapters - $32

  It's also not a bad idea to replace the hubs at the same time. more info: "Yes, you must replace the hubs from your car with the 98 or newer hubs. The newer hubs stick out about 1/4 inch. You will also notice that the ABS exciter ring is a better quality than the cheap pot ash crap that is on the 92-97's now. You will also need new rubber brake hoses as the ones on the 93-97 will be too short. You can either use 98 and newer hoses or go to a speed shop and have them make you stainless steel braided hoses like I did. If memory serves me right, the driver side length must be 16 inches long and the passenger side must be 17 inches long. Let's review: In order to upgrade your 93-97 brakes to the 98 and higher dual piston caliper, 12.4 inch rotors here is what you will need:
  

  • 16 inch rims to clear the calipers
  • 2 dual piston calipers
  • 2 caliper brackets
  • 2 12.4 inch rotors
  • 2 98+ rubber brake hoses
  • 2 98+ hubs Performance Friction Carbon Metallic brake pads
  • 1 bottle brake fluid

  Any questions please feel free to email me at mslv@aol.com" (2) threads on this: 12.4" brakes 1 & 12.4" brakes 2.

Intake, Mass Air & Throttle Bodies:

• K & N filters

  1. Flat filters -- these are the stock filters; the 1st thing you will want to do to get more air into the 4.6L. Check my notes on the K & N filter install for my '93 CV from the My '93 Vic page.

  2. Conical (GT-style) filters -- an "ok" mod as the conical filters will suck in HOT underhood air...consider a heat dam or an airbox with these. We all want the growl. Check out the fruits of Matt's labors on his K & N conical filter charger mod. Randy ('94 CV) just sent me some comments on another (even cheaper!) way to approach this mod: " I went out and tried to find the K&N Mustang GT filter for my car but It was $150 and I still wouldn't have a place to mount my oxygen sensor. What I did, is I went to Kragen auto parts and opened up all of the K&N conical filter boxes till I found one that had a 3 1/4 in. opening on the bottom (the size of the 70mm stock mass air). Then I marked and drilled holes and threaded the stock screws into the metal under the filter. Then I took my oxygen sensor and made a hole in the tube that connects to the mass air and out it in there. It works perfect. I get more power and a nice loud growl under acceleration. It cost me a total of $40. " Thanks Randy !

• Mass Air Meters

1. Lighting Mass Air Meter & Airbox with a www.customchip.com chip to tune it.

2. Pro-Flow -- Paul has had "ok" with this brand of after market Mass Air Meter on his '98 Crown Vic. If you go to their site, check out the Application Chart to match the CVs injector specs -- most are 19 pounds per hour. I'm not sure what the part number was, but check out Paul's ProM75mm Set-up on his '98 with a K & N conical filter -- the combo is as follows: "a mass air bracket and replacement K&N filter for a Mustang GT S trim kit (about $60 for both). a ProM75mm mass air meter (call Steve at Houston Performance and buy for $180). make sure you specify that it needs to be calibrated for an open air cone filter. notice how the Vortech bracket actually allows you to bolt the unit down to a stock mounting point =)." Sweet -- another pic of the ProM75mm (close-up).

3. C & L Performance -- These guys make a nice mass air for 19 and up injectors. Big with 4.6L Mustangers, the 73mm MaxFlow unit is designed for high performance Ford vehicles manufactured from 1989 to present. Also, check their high flow cats...meow ?

• Intake Tubes (new)

1. Volant Systems?!? -- Looks nice; I just found this off of Borla.com. Check out the tube for the F-150 4.6L trucks...this could work, I am going to find out the cost.

2. So far, I have NOT seen any intake tubes to replace the stock plastic intakes for Vics. Even so, I have seen LOTS of custom-made intake set-ups or adaptations from another application packages. Check out Wes' intake system on his '93 Crown Vic: Intake Pic 1, Intake Pic 2, Intake Pic 3 & Intake Pic 4. "We adapted the tube from a Nissan Pathfinder package. The length and the bends were similar to the routing we wanted in the CV. The pipe is 3 inches. The vacuum hoses (brake booster and the other [EGR?]) were tapped into the pipe using nipples that you drill a hole then set a lock nut inside the tube then tighten. The ends protrude into the tube about 3/8 inch which isn't much considering what the stock setup does to the air. The brake booster hose didn't need any alteration with the placement of the nipple but the EGR's metal tube was lengthened with less than a foot of rubber hose. The nipples were found at Home Depot and in fact if we didn't use the polished pathfinder kit (show and go) we could have used plastic pipe (abs or pvc) for a low buck system."

3. Kenny Brown's "Lounge Lizard" SNORKUS with the SVO/Eaton supercharger: Panther Intake Tube. I'd love to know who did this custom work -- very nice: black & bad.

4. There is a K & N Off-Road Performance Kit that works with most Vics -- Chris is installing it this weekend & will update on the HP gains. It is the K & N AIRCHARGER OFF-ROAD PERFORMANCE KIT -- part number 63-1008, WHICH IS NOT EMISSIONS LEGAL! K&N didn't stress that enough. Summit and/or Jegs has it for 78.99, the local speed shops were charging 120+, so go mail order! I will post Chris' comments on this thing at some point. There is also a K & N Filtercharger Injection Performance Kit Generation II, but no one I know has adapted one for a Vic. The air "dam" to keep out the hot engine compartment air is the really nice part. Check out this pic of one with the NICE, tiny AIT filter that goes on it: FIPK Pic 1 & FIPK Pic 2.

Transmission:

• Shift Kits for the AOD/AODE/4R70W

  1. Jerry's valve body mods are the best bet. Check www.tccoa.com for the details.

  2. TransGo -- Pretty nice kit, I have one installed. I have heard nothing but good things about this shift kit on the AODE Crown Vics & Grand Marquis. Hell, Matt is barking tires with his mods & the kit when 2nd gear engages ! I have seen this kit as low as $94 in MM & FF magazine.

     • Super Coupe's review on the TransGo kit

     • Transmission Exchange's info on the TransGo kit & AODE

     • A print out from the CV/GM TransGo kit (thanks, Liz!)

  3. B & M -- no data, but this kit is available & pretty cheap.

  4. Ford -- not much here; I saw the AOD shift kit on the '99 SVO catalog.

Engine Parts:

• Underdrive Pullies
  Paul sez: "These pulleys replace your crank, water pump, and alternator pulleys with ones that “underdrive” several of the accessories freeing up engine horsepower at higher rpm’s. Any pulley kit for a 96-98 Mustang GT will fit the 92 and up Crown Vics. The best kit available is made by ASP and is a “balancer” kit. While other kits require you to remount your old crank pulley on the new one as a harmonic balancer, the ASP does not (Geoff -- same with the Steeda kit). Also, the ASP does not affect your vehicle charging system. Some pulley kits will read low voltage when in gear and your foot on the brake at a stoplight. Unless your running a competition sound system, this really isn't a concern. Pulleys range from $120-$200 for the ASP “balancer”. Expect gains of 5-10hp with this modification."

  1. ASP (Auto Specialties Performance) -- here is an install walkthrough of the ASP pulleys.

  2. Ford SVO -- I'm guessing this SVO set requires the crank pulley to be remounted.

  3. Steeda -- Their kit comes complete with a replacement "balancer".

  4. March -- Note that Crown Victoria's must be changed to 6 rib belt for this set.

  5. MAC -- these guys also have some NICE exhaust stuff & cheap differential covers.

• Steeda Timing Adjuster
  More torque & 10 HP for around $180. I am dying to do this in tandem with ASP pulleys. I'm still trying to find out what the stock timing would be on the timing adjuster for the CVs, I'm guessing it is 10°, like on the GTs. Here is a nice article on the timing adjuster install & benefits from musclestang.com's modular GT section.

• "Shorty" Headers
  I put these under Engine Parts instead of Exhaust...I have heard these work great with duals if your have them gasket ported, but are a royal PITA to install by yourself in your garage / driveway...I think the clearances are pretty tight. Some commentary off the ONElist CV/GM forum: "after reading the Shop Manual procedure it appears that you have to disconnect the A/C system, motor mounts, radiator hose, etc because you have to jack the engine up 4" to get the headers in"

  1. SVO "Shorty" Headers -- also the cheaper Stainless Steel @ $260.

  2. MAC -- Long tube AND "shorty" headers. Download the entire MAC '98 catalog (1.8 Mg), get the catalog or order online.

  3. BBK -- some nice stuff here, like throttle bodies, too.

• High Performance Cams
  NOTE: (for the '91 & earlier model CVs -- I heard that Crane Cams is working on a CAM for the 4.6L engine that works with EEC) I think normally this is a no-no for most computer-controlled CVs (the GT cams would make most CVs bog badly), but I'm working on tracking down this Erson "RV" cam that works with the full-size Fords (with John's help). Just think, a well-planned cam swap could result in 40 to 60+ HP ! "The RV camshaft was originated by Erson Cams in 1972. Originally designed for use in heavy vehicle and towing applications, these camshafts have proven to be the perfect answer for late model, low compression engines, and are now used primarily in passenger cars, station wagons and light utility vehicles. RV Cams are suitable for use in otherwise stock low compression engines. Usable power is increased between 1500 and 5000 (depending on application). These camshafts have a smooth idle, excellent throttle response and acceleration, plus good fuel efficiency. For the best possible performance, the engine should be equipped with headers, a free-flow exhaust system, a small 4-barrel carburetor and a re-curved ignition system. These camshafts are ideal for sedans, station wagons, pick-ups, vans and motor homes. Suitable for over-the-road driving, trailer towing, etc. Idle is smooth and standard gearing is satisfactory. RV Cams are available for all late model American passenger car and light truck engines in hydraulic or mechanical designs."

  1. Erson Cams -- check out the catalog in PDF format (2.1 Mg) & see the Ford small-block stuff.

Exhaust Systems:

• Cat-Back Systems & Mufflers
  Paul sez: "If you have a single exhaust Crown Vic, yes, get the cat back. If you have a dual exhaust Crown Vic, save your money and just weld in some new mufflers. Flowmaster mufflers are cheap and widely available. Choose three chamber versions for sound similar to a stock Mustang GT, or 2 chambers for a deeper throatier 5.0 sound. Performance gain from a muffler change is nil. Going from single to dual exhaust will gain you 15-20hp. An addition mod for a extra 10-15hp would be a custom X pipe with high flow cats. An “X” crossover costs about $90 and can be purchased at www.drgas.com. Dr Gas also sells the high flow cats with a package along with the X crossover. A muffler shop can remove your stock cats and H section and replace it with 2 ¼ inch pipe. Exhaust pipe larger than 2 ¼ is useless at the power levels a non supercharged Crown Vic will make and will only cause lost low end torque."

  1. Magnaflow looks good.

  2. Dynomax -- My brand of choice (no drone). I got the Super Turbos...the race Magnums & Ultra Flos look just as good, but louder. =D

  3. Flowmaster -- Fairly cheap, great sound & gas scavenging insanity. Get the catalog online & start drooling. =)

  4. MAC -- Check out the sound of this "Pro-Chamber" pipe with ...Download the entire MAC '98 catalog (1.8 Mg), get the catalog or order online.

  5. Borla -- They offer a complete system with T304 Stainless Steel and the Borla intercooled turbo tips welded on. For '96 thru '00 CVs -- $460 at Summit.

  6. Dr. Gas -- Very, very nice 2 + 1/2 "X" crossovers & systems. Check these videos with a SVO supercharged GT outfitted with a Dr. Gas "X" pipe & 2 chamber Flows.

  7. MAC -- Look at their Pro-Chamber H-Pipe set up here on Mustangworld's How-To page.

• Muffler/Exhaust Sounds Online
  Check out a few of the popular systems & mufflers:

  1. Mustangworld -- MAC flowpath 2 1/2" cat-back, Powerchamber h-pipe, Dynomax Mufflers, Flowmasters, etc...

  2. The Corral.Net -- That unmistakable & racy Bassani sound ! Very exotic & NASCAR...

  3. More on the way..................

Rear Gears & Drivetrain:

• Rear Gears
  This is a GREAT mod for the Vics & Marquis cars...I ended up going with Ford Motorsport 3.73 gears, a new Ford Motorsport Traction-Lok unit (Ford's proprietary limited slip differential; clutches & "S" clamp style) and the 23-tooth speedo gear. Really wakes up the car, makes nice dual tire burnouts & the speedometer is dead-on accurate. Chris got 4.10s which are nice as well. Project "Lounge Lizard" went with 3.73s, so i followed suit. I had them installed at Ford Performance Specialists. 

  1. Ford -- My brand of choice. As far as I can tell, very nice.

  2. Richmond -- Another good brand...anyone have these ??

  3. Auburn -- If you are going to spend some money, these are excellent.

  4. Torsen -- These guys make a great limited slip unit.

• Drivetrain
  Get the Ford Police Interceptor Aluminum Driveshaft...a nice mod. Get a driveshaft loop put in there while you are at it. Hi-po Ford SVO U-joints couldn't hurt, either.

Superchips & Guages:

• reinhartautomotive.com Dennis chip is the best bet to my knowledge currently (05/01/02). The programming is top-notch by one of the best Ford perf / tranny experts in the US. Talk to Dennis, he will hook you up.

• Diablo chip is the very good as well.

• Superchips
  This is a VERY average mod...not much difference as i found. for the Vics & Marquis cars...turns your car into a "sport" version to some degree. I had the superchips.com brand flashed & installed at Ford Performance Specialists where they actually soldered the chip on, shimmed it to a perfect right angle & taped it in place. The stock "flash" has these changes -- firmer shifts, removed top speed limited, advanced timing (you will have to run 93 octane) and increased rev limiter a bit. NOTE: If you are in the market for a chip, check out this info from www.PerformanceFord.com (a superchip reseller): A brief review of Ford's EEC-IV vs EEC-V ( 'Electronic Engine Control' 4 & 5) and how they relate to superchips....plus Crown Vic cilivian VS. Police Package calibration differences!!!

  The Ford EEC-IV (eek-4) is an older processor style which had limited input/output pins and very limited diagnostics abilities. The EEC-IV had limited memory storage and many of the calibratons that were programmed into these modules were extremely small, limited in function and thus performance abilities. It should also be noted that these older EEC-IV "ECM's" (Engine Control Computers) had permanent performance calibrations installed. Thus, if a recall or similar performance problem was attributed to the ECM, the entire unit had to be replaced.

  With the modern Ford EEC-V (eek-5) there are over 100 input/output pins, it contains more than double the memory ( for calibration storage ) of many older EEC-IV units, and has live data logging and extended diagnostic capabilities when used with diagnostic scan tools. Also, the memory in these EEC-V units is called FLASH memory...meaning: the internal calibrations in your Ford/Lincoln/Mercury vehicle's computer (now called PCM, Powertrain Control Module) can be updated by connecting up to the diagnostic port inside the vehicle and downloading new calibrations. By the way, PCM is now the commonly used name, as these EEC-V computers now control both, the complete engine and complete transmission functions.

  While this FLASH memory provides many enhancements over older, slower "EPROM" style memory chips, it does provide a challange sometimes, for automotive performance enthusiasts, though. As with the EEC-IV system, whatever 'box code' or program code was listed on your ECM's label, you were assured that this is what program was loaded into your ECM. Nowadays, with the EEC-V and it 'ReFlash' capabilities, a vehicle owner could order a performance enhancing chip and run into trouble as the code he ordered, based on the outside labels, doesn't really match what is inside!

  Here at www.PerformanceFord.com we pride ourselves on selling only the best: Superchips Inc performance modules. As is the case, we program performance enhancements into our chips based on our customers 'box codes' which are found on the outside of the ECM/PCM and sometimes can be found in 1997+ vehicle's door jambs, by the hinges, or under the hood by the shock towers, on a white 1" sticker. See our website for full color photos and example computer codes, etc. Since these external labels are NEVER changed when a PCM is reprogrammed, a Superchip that is made for a code, VXX2, for example may not start a vehicle, as the true code may be VXX3, or VXX4 (example only).

  Also, with EEC-V Ford has found new ways to regulate limits on vehicles, when regulating the engine top RPM and vehicle top speed limits. Since these new challenges appear everyday to us, you must be careful when selecting a performance company that provides you with knowledge and cutting edge performance. Currently, Ford has introduced as many as two or three methods (or checks) to control an engine RPM limit or vehicle top speed limit; thus, if the performance tuning company does not know or understand how to modify ALL these different parameters, certain tuning changes simply wont take affect, as not all the limiter / checks are modified. Result: you will retain your stock engine rev limit or low vehicle speed limit, sometimes as low as 85 MPH as we have seen in the newer Ford Ranger series.

  Now, onto what we promised: Crown Vic cilivian VS. Police Package calibration differences.

  While we worked hand in hand with Superchips and did additional research in obtaining information on the main differences between a civilian crown vic and a police package crown vic, all efforts were made to double check the info and figures. If you believe a typo or other error is present or just want to comment, please inform Geoff, the webmaster, or link up to our site and email us.

  The fuel calibrations are extremely similar at part and wide open throttle (WOT). The ignition timing calibrations are extremely similar at part and WOT. The engine rev limiters are set near 5300RPM's in the Civ. and near 5800RPMS' in the police. The vehicle top speed limiter is 25% lower in the Civ. vs. the police. Most civilian crown vics appear to come in 2.73 gears vs. the 3.27 police pack. Major differences are seen at heavy throttle / WOT transmision shifting! Wide Open Throttle shift points are 400 - 700 RPMS higher in the Police Pack, depending on gear. Downshift points vary dramaticaly at heavy throttle / WOT! The police pack allows much earlier downshifts (as if in pursuit)... The police pack downshifts occur anywhere from 5 -12 mph earlier vs. civilian, depending on gear.

  Enjoy this data, we worked hard on researching it, we hope the wait was worth it! Note: Not all civilian vs. police package C.V.'s will carry the above similarites, but this at least gives us an idea... 

• Guages
  I am looking at the 2 or 3-pod a-pillar Mustang GT set-up from Autometer. If you want the tiny tach in there, try Intellitronix guages. The regular 2", 2+1/16" Autometers are very nice. How to install from Steve with the '99 Marquis: "Finally had a chance to use the heat gun to reform the late model autometer a-pillar gauge to the '99 Crown Vic and the results came out a lot better than I thought. Never in my wildest dreams did I think you could do this but the autometer pods fit like a glove....I'm thinking about doing it one more time this time with the 3-meter a-pillar pod that autometer sells through Jegs and Summit. One word of caution and that is to take the molding off the pillar then reform the pods to the stock piece taken off the car else you will scorch both the headliner possibly setting the vehicle on fire. I now just have to hook up the electricals and find a convenient hole through the firewall to cable up the oil pressure sensor but this is a project for this weekend provided the weather holds up."

• Crown Vic FAQ: http://www.crownvic.org/FAQ.html. an older version is below:

  What gears should I put in my car? 

  Gear choice depends on several things, it's a trade-off. The more gear you get, the faster you can accelerate, to a point. The trade off is that your gas mileage will suffer with each step up on the gear chain. Most civilian Crown Vics come with 2.73 gears, 3.27 in the performance and handling package (99-00 Vics with P&H get 3.55's). Police interceptors get 3.27's from the factory, which was upped to 3.55's for 99-00. All Crown Victoria's come with open differentials, which means you will only leave one mark when you try a burnout. 3.55's should be the minimum you should consider to up the performance of the Vic. 3.73's are a much better choice and are still very good with gas mileage. 4.10's would be about as far as I would go on a lightly modded Vic due to the fact you run out of revs at around 4250rpm. Regardless of which gears you choose, consider it a good time to replace your differential at the same time, the labor is not extra when doing a diff and gears at the same time. If you can, locate a used Mustang GT posi differential for $50-75. Most performance shops have these lying around after they get replaced. Most shops will charge between $150-200 for installation, add an extra $100 if your bearings are shot. You will need a 23 tooth speedometer gear to switch to any of these gears. With 3.55's, your speedo will read about 3mph slow at 65mph. With 4.10's, it will read about 3mph fast. 3.73's will read about perfect. Electronic speedometer compensators are available from Abbott for around $120.

  Is a K&N air filter worth it?

  A K&N air filter is worth about 0 as a performance gain. The flat panel filter can be a pain to clean, and gums up rather heavily in a small area, reducing airflow. Paper filters are cheap and do not require cleaning. Also, if a K&N filter is over oiled, it will secrete residue onto the mass air sensors, which will cause incorrect readings and subsequent pinging. If you want some real HP from a filter, consider a conversion to a K&N cone type filter. Depending on the year of your car, this may require a new mass air meter calibrated for the increased airflow. Proflow makes a mass air meter for the Crown Vic. It is the ProM75mm, and can be calibrated for stock or cone type air filters. Cost is about $200. Performance gains with stock air box and filter are negligible. Gains with ProM and cone filter are noticeable. Proflow can be contacted at www.pro-flow.com. K&N cone filters and a bracket that will allow you to attach the new filter to your stock air box mounting points can be purchased from Vortech at www.vortechsuperchargers.com. Be sure to specify that you need a replacement mass air bracket and K&N filter for a 96-00 Mustang GT S trim kit. The bracket is $20, the filter is $40.

  Will a performance chip give me more HP?

  The simple answer is NO. In stock form, most chips will not gain any horsepower. What a chip can do is adjust engine and transmission parameters for gear changes, shift points, etc. A stock Crown Vic has shift points set at apx 4000rpm, and rev limiter at 4500rpm. Chips like Superchips raise your shift points and rev limiter approximately 500rpm. Good, but we can do better. My recommendation is to follow Ford lead. On the 99-00 police interceptors, the shift points have been raised to 5000rpm and the rev limiter raised to 5250rpm. Chips can also be used to increase shift firmness, but their effects are barely noticeable. See below for recommendations on shift kits. Chips will also advance your engine timing to run on 92 octane. The gains are worth maybe 3-4hp and you are forced to buy expensive gas. Pass on the timing advance and get a timing adjuster from Steeda which is adjustable with simple tools. $150 from www.steeda.com. A chip can also be used to remove the top speed limiter which is set on most Vics to 106mph.

  Should I get a cat back exhaust?

  If you have a single exhaust Crown Vic, yes, get the cat back. If you have a dual exhaust Crown Vic, save your money and just weld in some new mufflers. Flowmaster mufflers are cheap and widely available. Choose three chamber versions for sound similar to a stock Mustang GT, or 2c chambers for a deeper throatier 5.0 sound. Performance gain from a muffler change is nil. Going from single to dual exhaust will gain you 15-20hp. An addition modification for a extra 10-15hp would be a custom X pipe with high flow cats. An "X" crossover costs about $90 and can be purchased at www.drgas.com. Dr Gas also sells the high flow cats with a package along with the X crossover. A muffler shop can remove your stock cats and H section and replace it with 2 ¼ inch pipe. Exhaust pipe larger than 2 ¼ is useless at the power levels a non supercharged Crown Vic will make and will only cause lost low end torque.

  Can I replace my 85mph or 120mph speedometer?

  Yes, Ford makes a 140mph speedometer for the Crown Victoria police package, and it can be swapped in. It is available at your local Ford parts counter for around $275.

  What are underdrive pullies?

  Underdrive pullies replace your crank, water pump, and alternator pullies with ones that "underdrive" several of the accessories freeing up engine horsepower at higher rpm's. Any pulley kit for a 96-98 Mustang GT will fit the 92 and up Crown Vics. The best kit available is made by ASP and is a "balancer" kit. While other kits require you to remount your old crank pulley on the new one as a harmonic balancer, the ASP does not. Also, the ASP doe not affect your vehicle charging system. Some pulley kits will read low voltage when in gear and your foot on the brake at a stoplight. Unless your running a competition sound system, this really isn't a concern. Pullies range from $120-$200 for the ASP "balancer". Expect gains of 5-10hp with this modification.

  Should I get a performance throttle body?

  Performance 70mm throttle bodies are worth about 1hp. I do not recommend them. The Ford and BBK (apx $170) ones fit the newer Crown Vics, but I do not know if they fit the older 4.6 with the forward facing intake.

  What type of performance plug and wires should I get?

  Any 9mm wire is pretty good. Also consider the 10.5mm & 10.4mm Taylor wires that are on www.brothersperformance.com. If you are looking for longevity, get a platinum spark plug. If you want better performance, get a standard issue non-platinum plug. I recommend NGK TR55, Motorcraft Coppers or Autolite 768 plugs. They are cheap and get the job done. Gap your plugs at .054. Any high performance wire set from a 96-98 Mustang GT will fit a 92-97 Crown Vic. Don't go overboard though, anything over 9mm is overkill. Don't expect too much performance from a wire and plug. Better wires last longer, cheaper ones fail faster, that's the main buying point.

  Do I need an aluminum driveshaft?

  If you plan on going with 3.55 gears or more, consider the Ford police package aluminum driveshaft, $260 from your local Ford dealer. It will help reduce the any vibration and humming your new gears will make. The faster you go, the faster the driveshaft spins. The lighter aluminum version will let your engine spin a little more freely and possibly add some hp.

  Should I cross drill my brake rotors?

  No, crossdrilling your brake rotors will only lessen the surface area the pads have to work with and make the rotors more prone to develop cracks. Stick with either stock Ford rotors (stay away from the aftermarket cheap crap) or Powerslot slotted rotors. www.powerslot.com I recommend Carbon Mettalic brake pads, you can get these at www.galls.com for about $100 for a full set.

  What shocks and springs should I get?

  Heavy Duty Bilstiens or for an even firmer ride, Koni's. Whatever you do DO NOT buy KYB shocks, they are terrible. Springs are a very limited choice. Eibach makes the only kit that I know of. It is part number 3532.140 and can be found at www.eibach.com and list for about $220. The springs will drop your Vic by about 1-1 ½ inches. The only other choice is police package springs. They will firm up the ride very well, but do not lower the car and are very expensive, like $400+. Also consider Tokicos...now on the Marauder & other Panther cars.