Police Interceptor Part Duex  - "What Ifs"

By: Sheriff Buford T Justice 
last updated 7/24/03

96+ SHO Police Pursuit What If

Say one does have a POLICE INTERCEPTOR badge on their fender, actually let’s assume they have 96+ SHO and they would like to know how their car would run against a real police interceptor, just out of natural curiosity because we all know one can’t out run the police radio.

One could visit the National Law Enforcement and Corrections Technology Center www.nlectc.org and download the latest "Michigan State Police Test of 2000 Patrol Vehicles," year 2000 that is - because the choices for patrol are limited to 6 cars and 4 SUVs.

From quickest to slowest, for the year 2000 they are.

• Chevy Camaro (5.7L SFI) in stick or automatic.

• Volvo S70 T5 (2.3L PFI Turbo) sedan or Wagon.

• Chevy Impala (200 HP 3.8L V6) replaces the Caprice.

• Ford Police Inceptor (4.6L DOHC SFI) which is a Crown Vic.

• Jeep Cherokee (4.0L) – 2WD or 4WD

• Ford Expedition – (5.4L) 4WD

• Ford Explorer – (4.0L) - 2WD

So how do they run and compare to a 3^rd Gen SHO?

Times are in seconds.

All tests performed sans light bar and the normal trunk full of essential departmental junk. All cars top speed limited by chip, one should not assume any vehicle is out of steam at their chip-imposed limit.

Using numbers from the July 96 Road & Track SHO road test, the Camaro is noticeably quicker than the SHO. We could guess that.

The SHO is quicker off the line then the Volvo turbos, then the Volvo is faster at speeds above 65 mph. Is that odd? The SHO is not known to be fast out of the hole and my parent’s T5 feels like a beast off the line? The difference between a SHO and T5 Volvo is very small and may not be important; I have never seen a patrol Volvo in use. With mods the SHO might skunk the Volvo except at altitude where the turbo maintains HP levels. The Volvo sedan only weighs 3320 lbs. and makes the same HP as a 3^rd Gen SHO.

Next are the Ford Interceptor and the Impala. Either is 2 seconds slower 0-70. The Impala weighs 100 lbs. more then the Gen 3, the Ford Interceptor weighs 500 lbs. more than the SHO. They are 15-20 mph slower on top speed if they don’t have a light bar or other external junk (like antenna or A pillar spotlight). Both of the cars are chip-limited.

The 99 and prior Crown Vics had a 2.73 final gear ratio, which put it in the SUV performance category. It took forever for them to get to speed.

So how come they seem so quick? My theory is it is because the drivers don’t pay for their own gas or for repairs. Even at 2 seconds faster 0-70 – It is different situation winning a street drag by 2 lengths, or an unhappy patrol car one length off their rear plate. Ask me how I know this to be true. ;-)

The Jeep police SUVs out-run the Ford police SUVs. Neither can touch a SHO unless you choose to do a lot of off-roading in your SHO.

"Vehicles were driven on a 1.635-mile road-racing course containing hills, curves and corners and except for the absence of traffic simulates actual pursuit conditions" – ok, and they did not take the Ford SUVs on the track because Ford does not recommend them for pursuit work. Makes sense to me. One and a half miles in 90 seconds equals 60 mph so 1.636 miles in 1:20 or 1:27 indicates average lap speeds of ~ 70 mph. Note that the spread of times is only 7 seconds and if we assume the SHO is on par with the Volvo it again splits the difference between the Camaros and the Ford - Chevy sedans.

Using information from the MLECTC most recent (1999) test of Patrol Vehicle tires the Impala on best tires generates .694 "G" on a 200’ diameter dry test circle. The best Ford Police Interceptor was .688 "G" on the same dry test circle. Car and driver (July 96) rates the SHO at .79 "G"; and that is with the small OE anti-roll bar.

Best speed for the Impala for a dry 700’ slalom is 54.5 mph, the Ford Interceptor best was 53.41. Road and Track (July 96) reports the SHO speed for a 700’ slalom as 61.0 mph, much faster. Are the slalom laid out the same – are the times comparable? I don’t honestly know, I think they are.

I have 3 lessons I would like to share.

• One could assume from the above that the OE SHO should handle much better than either police sedan. I one had occasion to follow 2 MD marked cars across the MD pan handle (I-68) at speeds of about 100 mph for and extended period of time with my scanner on. They were having fun "doing the mountains" at a velocity I found it very challenging. They obviously knew the roads well and the cars were comfortable at those speeds. Flying blind into an interstate sweeper at 110 with a 1000-ft drop-off past the guard-rail is not as easy or relaxing as one may first assume.

• Second I have a poor man’s G meter. A 2" Saint Benedict hanging from my rear view mirror. It is a heavy bugger and spiritual advantages aside the tangent the angle chain makes from plum indicates G forces. Typical cornering forces are almost never near the theoretical .79-.80 limit. If you tried this, the first corner with an uneven surface, oil spot or dirt would send you into a guard-rail in a flash. Having an advantage and using the advantage under street conditions are two very different things.

• Someone who would know said the police don’t chase drivers, they just follow a driver from a safe distance and wait for the pursued to make a serious mistake, then swoop in and collect the pieces and do the paper work. Recommended follow distance is a few hundred yards. If the police spot a car a few hundred yard, a two car length performance advantage does not amount to much. Ya can’t out run the radio …

From MLECTC again "As can be seen from the California pursuit data for the 3- year period of 1994 through 1996. A collision occurred in 26 percent of all pursuits. Over one-half of all pursuit-related collisions occurred in pursuits lasting 1 to 2 minutes; more than 73 percent occurred in pursuits lasting 1 to 4 minutes; 83 percent of the collisions occurred in pursuits lasting 6 minutes or less."

In case you don’t get it, the chance of a person wrecking their car and getting in a huge amount of trouble running from the police is real high. My argument is that the SHO is a better car, not that running from the police ever works. Ya can’t out run the radio…

so …

Hey, lets be safe out there!

DISCLAIMER, this study was undertaken out of academic curiosity, nothing here should be interpreted in any way as encouragement to do anything stupid, reckless, irresponsible and criminal on public roads. Those sorry criminal pukes dumb enough to run from law enforcement will be caught, prosecuted. Running from the police is illegal, immoral and not very smart. Those who do risk their life and the lives of police and other innocent bystanders deserve whatsoever they get in court. If you read this and go out and hurt somebody the chair is too good for you.

From the National Law Enforcement and Corrections Technology Center for model year
2001:

"Ford beefed up the Police Interceptor with a new 235-horsepower 4.6L V8 engine and reconfigured last year's rear axle ratio of 3.55:1 to 3.27:1 for improved fuel economy. Ergonomic and safety improvements include improved seats with power lumbar adjustment offered on the driver's side, a weapons cut-out feature added to both front seats, and optional adjustable-position accelerator and brake pedals. For personal safety, Ford engineers have designed an advanced restraint system that works via a combination of seat belt pretensioners, dual-stage air bags, and seat position sensors that adjust air bag deployment speeds. The sensors monitor both the seat position and the passenger weight of the seat occupant. "

AM General Hummer has a 0-90 time of NEVER but is rated for pursuit work.

Ignoring the SUV's because they don't change much and are not all that fast.

Top Speeds

Hummer  -88 mph  (0-80 in 49.27 sec) (snicker)
Camaro (Auto) 159 mph  (0-100 13.93 sec)
Camero 6 spd - 159 mph  (0-100 13.35 sec)
Impala - 124 mph  (0-100 25.40 sec)
Tahoe 2wd - 98 mph
Tahoe 4wd - 98 mph
Cherokee 2wd  - 111 mph
Cherokee 4wd  - 111 mph
Ford police interceptor 129 mph (0-100 24.61 sec)
Ford police interceptor (CNG) 123 mph (0-100 37.02 sec)
Ford excursion 4wd  94 mph (0-90 in 26.34 sec)
Ford Expedition 4wd  106 mph (0-100 in 34.32 sec)
Explorer 4wd  106 mph  (0-100 36.22 sec)

0-60 for the new ford police interceptor is 8.7 sec
0-60 for the new Impalla is 9.2  sec

A stock V8 SHO should beat the PI by almost a second.

This is good news the new police cars are dawgs.

None but the Camero can brake with a stock SHO.

The new PI has 20 more HP, but taller gearing. 0-60 is unchanged but 0-100 is almost 2 sec quicker.

I feel much safer now. I hope you do too!


Buford T. Justice

Tim,

In re: 96 SHO v8 vs police vehicles, you forgot one huge item:

During all MSP tests, the cars are tested with one driver, one passenger, and a full tank of gas.  It says so right up from in the full test reports (but not in the test briefs on the NLECTC website).  MSP tests ALL the cars that way because it more adequately represents the weight conditions of a single driver + police equipment (radios, guns, evidence collection bag, tools, prisoner cage etc).

So when you take the SHO performance data, you can't just use the best-ever data taken on a drag strip with a minimal fuel load and just a driver.  You need to revise the performance data to reflect a full tank in the SHO and having one rider up front.

I don't know what the average weight of a cop is, but I usually assume that the  driver + passenger + full fuel  will add roughly 500 lbs weight to the curb weight of the auto.  I also don't know if the curb weight listed in the MSP data already includes the full tank.  If it does, one could assume adding 400 lbs of weight to represent the driver + passenger.

Now I've used modeled data, using either CarTest or QuarterJr, then added 400+ lbs, and retested the software, and I've compared it to the results from MSP tests from 1989 up to 1996, especially for the Caprice 9C1 (with several different v8 engines depending on the model year: LO3, LO5, L99, and LT1), the Tahoe, the Ford Crown Vic (with several flavors of 4.6 sohc and a 5.4 sohc just for kicks), as well as the Camaro and 2000 Impala police models.

The software simulations match very closely in all acceleration aspects, the MSP test data for ALL of the above vehicle (as it should), so long as the extra driver + passenger weight is included.  One also has to factor in the air temperature on the day of the test, since warm or hot weather reduces engine performance.

So that's a long-winded FYI.  The Taurus SHO data seems what you might get for a driver-only acceleration run.  You can very easily duplicate my methods, by taking the SHO test data, putting it into CarTest or QuarterJr, tweaking the model until it closely matches the results, THEN add 200 to 500 lbs to the car weight and then rerun it.  I say 200 to 500 because the model data you use may, or may not, already have a driven included.  It should already include the driver, so you might need only add the weight of the rider plus a full tank of fuel. Rerunning the model will then give you the data you need for comparison to the MSP test data.

As a final data point: I know my '94 Chevy Caprice LT1 (engine) 9C1 (police package) ran 15.0399 @ 91.99 mph at 602 ft above sea level, in 75+ deg humid weather, with a 230 lbs me plus full size spare, toolbox, jack, a briefcase, and two children car seats.. and that was at 122k miles on the odometer.  I have the time slip from Lebanon Valley Dragway in Lebanon NY from 1999 to prove it.

My run was, and is, typical for a stock 94-96 Caprice or Impala SS with  LT1.  This corrects to 14.96 @ 92.5 mph at sea level, but not temp corrected.  I also ran the car a second time and ran 15.12 @ 90.9 mph, when the engine was heat soaked and with a leaky right front tire.

The best MSP test for a 94-96 LT1 Caprice was 16.02 @ 88 mph (1996 data) in the quarter mile, so the difference between the MSP data and mine is significant:  1 second and roughly 4 mph.  All the other acceleration metrics are similarly affected by the excess weight in the MSP test trim.

I'll add that the braking tests are ALSO done with the extra rider and whatever fuel is still in the tank (still close to full).  So the extra weight also affects (lengthens) the stopping distance, but it would be difficult to try to predict by how much.

I'll lastly add that most of the vehicles tested have speed limiters. In fact, the Camaros are limited by the MSP drivers to NOT exceed 160 mph for safety reasons.  Almost all of the vehicles are have computer-based soft fuel shutoffs (at the injectors) to limit the vehicle speed to the tire ratings.  The Ford Crown Vic (police interceptor) is limited to 130 mph, even though it ran 135 mph during the 1996 test.  The Impala 9C1 could run 130-131, but it is limited to 124 mph.  The other reason is that once a lightbar is installed, the vehicle top speed(s) will likely drop by 5+ mph anyway.

The police cars are not as doggy as you might think.

As an afterthought, go find the quickest test of an 2000-2001 Impala LS with the 3.8 v6 and 4-wheel disc brakes.  0-60 is around 7.5 sec, and the quarter in 15.7 sec.  These times are close to the V8 SHO.  The braking might be a wash, or even favor the Impala LS.  SHO wins in top speed because it has 230 hp, whereas the Impala only has 200.  The torque/weight ratio for both cars is very nearly the same, and the size & frontal areas are similar, so the acceleration should be similar (which it is, for similarly tested conditions of weight and fuel).

FYI and HTH.

- Ken, still waiting for someone to put a sohc 5.4 into a Crown Vic

______________________________________________________________
Kenneth D. Rolt, Ph.D. '94 Caprice 9C1
mailto:kdrolt@alum.mit.edu callsign: KB1FFM

7/24/03

Tim

I figured I'd read this article to see how they would (in theory) perform against the SHO... I read some things, and I can't really vouch for them all, BUT I can say the Crown Vic is governed higher than the site that you got the info from says. I've been in many different models of P-71 Police Interceptors over the years, and I've never had one to lose steam anywhere near 129. All the ones I've ever been in were governed at 142, although after the light bar most of them wouldn't touch it. The highest I had seen a speedometer go was DEEP into the 130's, approaching 140, but due to the conditions that night we were unable to break the 140 barrier.

However, I can tell you that the Chevy Impala's DO shut off sooner. But, for whatever reason I believe that the governers that are listed on that site are actually for the normal family cars... Because that was where the non-police package interceptor at the local PD that the assistant chief of police is driving, and he came to me, and asked me to remove his governor... I asked why, and he explained to me when he ran outta juice, the crown vics pulled so far ahead he had to give up on the chase.

*Also there is a diablo modified interceptor in town that'll peel the paint off the doors of any other ones in our area, and they say he is faster by a long shot. I can't wait to get in it. :-D.

AND I wanna get into the police Camaro's, with that low roof, and the long doors, that could pose a little problem for it's purpose... However, for specifically high speed pursuits, I can't see it getting much better.

Oh, and the officers don't pay for their own gas here unless they are using the vehicle for personal use (clocked out). Also the repairs on the vehicles are not the responsibilities of the officer, thank God for that. And, most of the labor is free on the account of there being so many mechanically inclined "trust-ee" inmate, who are working for 'jail money' (which ultimately probably means cigarettes)

Marcus McKinney

Thank you very much, I value your input. The page covered 2000 & 2001 models so if your PI is 2002 or 2003 or 2004 your results may vary.

Tim

see also 2003 Police Interceptor Update

Your welcome, and I'm happy to be of service. The years varied from 1996 to 2002, covering several years in between. I am unsure of the new impala's police package, because I've only seen one civilian model that was used as such, it DID however shut off early, as I stated earlier... Nice cars tho :-D

Marcus