40mpg (half) tank in the s10

[kir_kenix]

Well, I finally achieved one of my long term goals in the dime! I drove down to my dad's house to do a final walk over of his roof we will be slapping shingles on this weekend and decided to see what sort of mpg I could get. 207.7 mile round trip, avg speed of 42 mph on a tank of e10. I knew I had a really good tank going (SG indicating 39.7 on the return and 42.1 on the way down), but I didn't know for sure until I coasted through town and filled up. Hit the magic number of 40.25 mpg!

I installed a new lower grill block (my old one had disintegrated) and finally re installed my lawn edging air dam that got ripped off in the snow this winter before driving down. Didn't have on the flat wheel covers or I probably could have hit 41 or 42. Alternator disconnected on the way down, coasting in N on smaller hills and EOC on bigger descents. Temperature was in the mid to low 70's. 300 lbs of stuff (air compressor, nailers, misc. tools) in the box for the trip down...empty on the way back.

I was pretty ecstatic to say the least. I will not be able to duplicate this on a regular basis because of the amount of effort/patience required...but I now know it can be done at least. I would have been so bummed if I would have gotten 39.9 or something like that because I know there were so many times I made little mistakes on this trip: such as neglecting to put on the smooth wheelies, braking for a few lights I thought I could make, etc, etc.

It gives me some inspiration for my regular commute where I have been averaging just over 30mpg, and gives me a new goal to meet (45mpg!). Pretty sure I could do 45mpg on this trip if the weather was a little warmer, I didn't have junk in the back, went during daylight hours so I wouldn't have to plug in the alternator for the return trip, wheel covers were installed, and I finally completed my 2/3" drop. Guess this just gives me another reason to visit the family


Vehicle specs:
1997 Chevy s10 regular cab
2.2L
5 speed manual (3.73 rear end)
tires at 40psi

Mods (that actually helped):
LED's all around
Choroplast toneau cover
air dam
lower grill block
PS delete
Alternator delete
WAI
E fan
15 watt solar panel
recent tune up and front end alignment

Thanks for all the help along the way guys! Couldn't have done it without Ecomodder.

[elhigh]

Wow, That's Fantastic!

[MetroMPG]

40 in an S10 - impressive. Congrats!

[kir_kenix]

I'm pretty pumped for my next round of commutes. Now that I know it is possible to get this kind of mileage, I really need to work on getting better economy on my 35 mile trip to work. I would love to see 35-36 regularly this summer. In the past I've only topped 35 mpg on a handful of occasions and usually while on sustained trips.

[MarkM66]

So you completely removed the alternator, or just have in on a switch?

Nice work. Any pictures?

[Daox]

You're doing very well! I have the same engine in the sunfire, but with my automatic transmission its hard to achieve the mileage you're getting.

[kir_kenix]

Originally Posted by MarkM66

So you completely removed the alternator, or just have in on a switch?

Nice work. Any pictures?

I just have it disconnected via plug right now. It free wheels and improves my mileage somewhere in the 1-1.5mpg range (some folks are reporting much higher). Since it is a single wire, I will eventually wire up a toggle switch inside the cab so I can kill it on the highway and flip it on whenever I am on a descent where I am coasting. I have also noticed that my mileage severely drops if the battery is ever allowed to fall below 11.2 or 11.1 volts. I'm sure at this range that it makes the coils and/or plugs become less efficient.

"You're doing very well! I have the same engine in the sunfire, but with my automatic transmission its hard to achieve the mileage you're getting."

I imagine you must have the 3 speed then. I have no idea why GM thought it was a good idea to pair the 2.2 to a 3 speed. My neighbor has a Sunfire with the OD tranny, he says that he usually returns 32-35 on trips.

I've also dreamed about getting a Sunfire with manual everything, stripping the interior/door panels/seats/sound deadening, dropping a mildly built 2.2 Ecotec (no ps, air conditioning, etc) with a manual tranny and see what I could do for fuel economy. I'll bet a totally stripped Sunfire could get down to around 2,000lbs...coupled with a 135-175hp motor and a tall overdrive would be good for 60mpg with plenty of zip when one got on it.