Just snagged a 2003 buick century w/3100

[IsaacCarlson]

What are the top mods for mpg? I will up the tire pressure, delete power steering, a/c bypass, wheel skirts, belly pan, intake, synthetic oil/trans fluid.

Is anyone else thinking of something that I am missing. This will be a daily driver for my wife.

[RobertISaar]

if you're going to go that far, you might as well swap the 3.05 final drive and 35/35 chain set with a 2.86 35/35 set or go even further(37/33 chain with the 2.86 differential would allow 2.55:1 final drive.

[justme1969]

eco tuned puter would be best opening one shot.
I think all century are auto stick so above was best trans idea.
To get that gear down, unless you are primarily a city driver. and there isnt alot of extra room for larger tires under front.
A 3100 is a medium sized engine that acts large.
The chevy interceptor is a similar engine with better flowing exhaust, cooling, and puter.
There is also a cool mod for a Dual charged turbo/supercharged 3.8 buick engine, but it is more for drag racing.

[slownugly]

these engines get pretty darn good mileage even completely stock. (for an older v6 design) i got 31-33 driving 80mph on an 8 hour trip with my grandmothers 96 olds cutlass with the 3.1- ive had customers report similar mileage.

yea they sell some crazy aftermarket stuff for the 3.8. all different cams and heads. turbo conversion. i think i saw a late 90s pontiac grand prix gtp in the 9's

[pete c]

How exactly do you do a PS delete? Is it simply removing the belt? If so, I would not do it with a car of that size, especially if your wife will drive it.

If it is a matter of converting it over to a proper manual steering, it seems to me a lot of work for not much gain.

[hondaguy72]

Had the same car. The best technique I found was keeping under 60. I averaged around 30mpg on a 35 mile highway commute.

[mcrews]

I would hesitate to remove the ps and a/c if MY wife were driving.

come on....do the math.
a happy wife is worth the 2 bucks aday you'd save on in gas.....

[mcrews]

and there is always room for a slightly taller tire when it comes time to replace the tires.

[IsaacCarlson]

The p/s delete is easy. I did it on the olds. I take the vanes out of the pump and disconnect the lines, then refill the pump to lube the bushings and loop the lines at the rack with most of the fluid drained.

It was easier to steer the olds with the manual steering than it was with the power steering. Call me crazy but my wife loved it.

I have the 4t60 out of the olds if it will fit. That had a 2.84 final drive compared to a 3.05 in the century.

The 3800/4t60 from the olds will go in the century, and the 3100 from the century will be mated up to the 4t40 in the sunfire. Then the sunfire can be sold as a conversion for some college kid to play with, my wife can drive the century, and the money from the sunfire sale will pay for part of the cost of turning the pole shed into a house/shop.

There, I figured it out. What say you wise people of ecomodder?

[IsaacCarlson]

ok, I just had an idea.....

what if I sold the sunfire and 3100 as is and just let someone else put it together? I should be able to get a few thousand for the pair right? It would save me the time.