10 MPG (61%) Improvement

[24601]

Originally Posted by dirtydave

What techniques are you using? That's a huge jump.
And what's next ?!#!

Avoid heavy traffic, choose routes with fewest traffic lights and turns, avoid idling (bye bye drive thru), monitor rpm/throttle position/engine load. Use momentum when possible.

There are some mechanical and aerodynamic changes on the horizon that I'm going will push me solidly beyond the 30 mpg threshold.

[Baltothewolf]

Originally Posted by 24601

Avoid heavy traffic, choose routes with fewest traffic lights and turns, avoid idling (bye bye drive thru), monitor rpm/throttle position/engine load. Use momentum when possible.

There are some mechanical and aerodynamic changes on the horizon that I'm going will push me solidly beyond the 30 mpg threshold.

Yea aero does make a difference. My best friend has a '91 crown vic and he got 34mpg once driving 65 on the freeway (he used to drive around 400 miles a week to work and back, same as me). I think he more averaged around 29-32 depending on how his right foot behaved.

[racprops]

OK First I have a 2000 Mercury Grand Marques more or less stock and I can get 27/30MPG if I stay under 70 MPH and 24/26 around 80/85 MPH high way.

I am running a 99 P71 CPU, and "stock sized" tire and rim to 18 inch wheels and tires...(same size as original)

And I can get it to do 34/35 MPG under 70MPH IF I can stand running 16.7 to 1 Air fuel ratio..but it does lose a lot of power doing that.

So far I have not figured a way to do that FR automatically so it is a pain to set it up and to return it to stock.

Question is there any newer 6 speed autos that will fit behind the 4.6??

OR better yet either a second Over Drive or two speed rear end giving it 8 speeds?

Rich

[David Philips]

You see that how and where you drive is huge. Bigger than an axle change can get you I'd bet. You're saving two gallons every 100 miles. Percentage wise you cannot get that big a gain yet again. I'd go with the 2.73 and go with the auto trans. Most all auto trans lock up fairly soon and they'll give you better response at low speed and very low rpm because the torque converter will let the engine rev a bit. A std trans with a 2.73 would be dog and tough on clutches. When you do the axle swap start with some test cruise runs at say, 55, 60, and 65 mph and you'll be astounded how the higher speeds hurt your mileage especially with a big vehicle like the CV. I'm guessing at 60 mph you can easily do 30mpg day in day out.

[serialk11r]

A Crown vic? Now *that* is a car I'd pour money into if I had one. It inspires fear in the hearts of other drivers on the road and cops think you're one of them. I don't know how much money it would cost, but have you considered engine mods? Shaved heads and reground cams should buy you some gas mileage. Definitely go for the manual transmission if you can, if not maybe install a manual lockup switch if possible.

[racprops]

Has anyone checked to see how much an air brake the rear bumper cover might be?

A manual lockup switch what for, light throttle and it locks up by its self and will unlock without a down shift on slight loads/hills.

These cars are very well set up stock, and yet can HOT ROD with a lot of cars, I need a posi because I can burn rubber TOO easy..even with wide performance tires.

Now that the summer heat is over I will be trying to get that extra 5 MPG....

Rich

[RiderofBikes]

The only thing i can think of off the bat for this particular vehicle and its drive setup, would be an aftermarket Under/Overdrive unit. Granted this is a hefty $ addition... even a simple rear end change could add up just as quick.. Probably not the most ideal since you have to manually engage/disengage the unit, if this setup was controlled by an computer controlled setup, kinda like a FI boost controller setup in corilation to Boost pressure:throttle position, or speed:gear. This would probably be better for larger vehicles.

[racprops]

I would like to put in a posi rear end and add a simple second over drive...

And perhaps do a rear bumper cover tuck.

And I will be working on the engine and fuel system.

Rich

[bikeprof]

Hmmm, many of the lost MPG's of this "boat" are in the AERO mod section to get it to 30MPG+.

1.Cover the rear wheels
2.Tire deflector tabs
3.Underbody coroplast cover(signs, free signs...!)
4.Front air intake closure

many more but these would be a great place to start

BTW, way to go teaching your right foot to ease off