The 40MPG Crown Victoria Challenge

[gabi]

so why are underdrive pulleys not good?
i'm actualy thinking to get a set,most people love them.
i also have a crown vic,but the police interceptor where the idiling is set higher,i think underdrive pulleys can only help in my case

[Christ]

Frank, that's missing the lawn chair, and that thing has HORRIBLE aero!

[Frank Lee]

I was looking for the pic of the Hot Rod mag article from 30 years ago where they gradually stripped a car and did 1/4 mile drag runs. Ultimately there was nothing left but the running chassis, the firewall, and the driver's seat. My cousin did the same thing to some old heap and nobody could beat him.

[comptiger5000]

Underdrive pullies will help a little, but not a whole lot. The problem is, they slow down the water pump and alternator, which when keeping the rpms down for fuel economy can present problems, depending on low rpm alternator output, etc.

[UFO]

You realize gains with underdrive pulleys when your typical rpm range is high, like the street racers like to do. The power gain is miniscule, but they look cool with various colors of anodizing.

[darcane]

Originally Posted by mystere485

this is true, it will be used for highway driving, 2000+ km trips at a time.

there are members getting 24-25 mpg with no mods in their crown vics. Ok, so we use that as a base. First mods:
LRR tires and light weight rims
Replace the engine fan and clutch with an electric assembly
underdrive pulley
build a front air dam and belly pan
block off the bumper intakes and replace the grille with 1992 style model
HAI
tune-up, oil and trans fluid change
get rid of the spare, jack, replace the front bench seats with newer buckets
Replace rear side and quarter glas with plexi
lower car 2 inches

If feasable, swap intake and exhaust manifolds and switch to PI heads.

should these mods not get me to 30 mpg?

Aero:

• build a front air dam and belly pan
• block off the bumper intakes and replace the grille with 1992 style model
• lower car 2 inches

These will help, I'll be optimistic and say 10% gain here.

Weight loss:

• get rid of the spare, jack, replace the front bench seats with newer buckets
• Replace rear side and quarter glas with plexi

This will have minimal impact on highway mileage. Weight has more impact on city driving (start/stop) and lots of hills. I'd guess less than 1% gain.

Other:

• LRR tires and light weight rims - could be 2-3% if combined with higher tire pressures.
• Replace the engine fan and clutch with an electric assembly - no impact on hwy mileage over working mech. fan with clutch.
• underdrive pulley - small gain, less than 1%
• HAI - small gain, less than 1%
• tune-up, oil and trans fluid change - no gain, this will only make up for a loss of mileage you may have.

If feasable, swap intake and exhaust manifolds and switch to PI heads. - small gain, probably not worth the cost.

Optimistically, I'd put you in the high 20's with what you listed. 30mpg would be a stretch.

You say some are getting 25mpg with those... Have you put any miles on it yet? What do YOU get with it?

Higher tire pressure and driver education are the free mods you should start with. Get an Ultra-Gauge or Scan Gauge (I didn't catch the year, it's 96+ right?). Then start picking the low hanging fruit, lighter wheels, aero wheel covers, grill block, etc. Once that is done, see where you are at and go from there.

[Christ]

Originally Posted by UFO

You realize gains with underdrive pulleys when your typical rpm range is high, like the street racers like to do. The power gain is miniscule, but they look cool with various colors of anodizing.

You don't gain any power at all with underdrive pulleys... they reduce parasitic power loss. Yes, there's a difference.

[slowmover]

I'd go for 30-mpg. Keep the virtues of the road cruiser intact and make only small, reasonable changes in gearing and aero.

An 800-mile trip (1300 kms) at $4/gl at 40-mpg = 20-gls, or $80.

The same trip at 30 mpg = 26 gls, or $104

Pack a lunch and eat at a picnic area. Save the $25 this way. Or take a paying passenger.

The virtue of the CV is that a well-maintained one lasts many, many years and miles.

[dcb]

I'm not really familiar with the use of the term "virtue" in this context

[UFO]

Originally Posted by Christ

You don't gain any power at all with underdrive pulleys... they reduce parasitic power loss. Yes, there's a difference.

It's a net power gain. How is that different?