The 40MPG Crown Victoria Challenge

[Frank Lee]

In the absence of a BSFC chart I'd shoot for 1000ft/mn piston speed at cruise... just because.

[roflwaffle]

I don't think we even need BSFC maps. Just about every engine I've seens from a 1L 3 cylinder gasser to a 7.5L diesel from a semi gets decent BSFC at high load/lower speeds compared to crap at low loads. Gear it so it's at about half load at least and someone should be good.

[Frank Lee]

Yeah but you don't want to lug it either, even if you're only asking for 16 HP. Frinstance the Sport Coupe is already at 1000ft/mn at 50mph... could gear it up a skosh but not much.

[roflwaffle]

That's true, and it's pretty easy to figure out whether or not something is going to be operating at 500rpm or something. My pickup will do 25mph/1100rpm with a light foot, and it's a carb'ed i4, so a fi v engine should be able to do better.

[XJguy]

You are starting out with a car that has a fairly good aero package. Don't let its large size make you think otherwise. One thing that was implemented in later models -up to current is a new trunk lid that incorporates a bit of lip/spoiler. This was done to improve aerodynamic efficiency. An addition of some aluminum angle bar adhered to your lid, should act as a Gurney flap and bring you the same result...a clean break for passing air.

I would further enclose the rear wheels, vent all 4 wheel wells, vent the radiator through the hood. Remove any mechanical fans for electrical ones. Swap out the heavy cast iron brake components if so equipped, and substitute for light weight aluminum. Police Interceptor models have many high performance parts that may actually weigh less, being made of aluminum alloys instead of steel.

A lowered car is only more aerodynamic if it is done so in lieu of an underbody that is smooth. With a smooth underbody there is little need to lower the car (aside from handling). However you do have to compensate for the gapping holes of the wheel wells, which should be a close tight fit to the wheels. With a car that is very low you start experiencing a ground effect in which the car is sucked down into the pavement, which increases traction, but also drag....if not managed by a proper venturi and or spoiler/wing, at high speeds it can render you airborn.

If I am not mistaken behind those plastic fascias is a heavy steel bumper...that too can be nixed for nothing, or a lighter home made option, or trimmed, dont know if any year models cane with aluminum back there as so many new cars now do.

[ranger40mpg]

I'm starting my ford ranger 4 litre standard shift project. Mine is an 09 2wd. So far I'm running synthetic oil in it and have added a bak-flip over the bed. Stock it got 27mpg to a canadian gallon. After just the 2 mods it's very close to 30mpg at about 100 to 105kph. I've also inflated the stock goodyear wranglers to 40 psi. The ride is choppy already so I don't mind. I'm driving 4500kms to British Columbia and will post my mileage at a later date.
I have a question to ask. Has anyone put that 69 dollar power chip in their Ranger 4 litre and what have your results been. Thanks guys and I'm looking forward to bangin heads.

[comptiger5000]

Considering that mine will effortlessly accelerate at 1/2 throttle from 37mph at around 1100 rpm in OD with the TC locked, I'd say I could gear it A LOT taller and still cruise comfortably. It's only at 1050 fpm turning 1760 rpm at 60mph now though.

I figure I could probably be fine with throwing a gear vendors on it and turning about 1370 at 60mph. It would need to downshift on most hills, but it should pull fine. The 4.6 Ford doesn't have a ton of low end torque (especially in car applications), so 1300 or so at 60 is probably the lower limit before power drops off too much, potentially causing it to be running under enough load to hit fuel enrichment.

[Big Dave]

Just a word of encouragement.

I just spoke with a guy who has a 94 Caprice. The Chevy B-body is very similar to the Ford Crown Vic. Maybe a couple hundred pounds lighter. 305 cubic inch TBI V-8. 4L60 automatic. 2.56:1 gears in a GM 10-bolt axle.

He claims AVERAGE 29 MPG and the car is essentially unmodified.

So 40 MPG is not that far off.

Roughly average hypermiling
A ruthless weight reduction program
LRR tires (orobably Goodyear Fuel Max or Michilin HydroEdge)
3.08 or lower gears
A diesel engine
T-56 transmission
Grille block, belly pan, fender skirts, MoonEyes, some sort of rear deck treatment

That should get you there.

This guy's success tells me I could get 30 out of my Imp with a gas engine (L92), a T-56, and some aero mods.

[Frank Lee]

Well, 33% is a ways off...

Good luck beating much smaller cars with smaller engines and manual transmissions that have to struggle to hit 40...

[Big Dave]

I have achieved a 40-50% improvement in my truck's MPG with just driving, gearing and some light aeromods. I started out with a diesel and a stick. A 40 MPG Crown Vic would get huge improvements with a diesel engine and a manual transmission.