26.2 mpg Toyota Previa. Go Golden Egg!

Thank you. I have the 15" alloys...was thinking about getting Rotas though, in flat black, they weigh 11lb each, just need to find the tires... I've been researching a little, and a few are ELRR but they are loud or reviews say they wear out fast. The tires that are quiet, aren't that low RR...

I consistently get 20mpg city/22-24 highway, with all but one of the rear seats out (the one furthest back, not the boat anchor captain's chair, I keep it tuned up, proper tire inflation and lighter than stock wheels and LRR tires. I couldn't give up my AC and power steering, and all the other stuff for a 3 mpg difference. You must live in a cold part of the country? I drove a Honda civic for three years that got 40mpg. I finally sold it because I was constantly roasting in it, sweating upon arrival at every destination with wet clothes, because it had no AC. I bought the previa because I had one before and mostly to have a car with AC, and the one I had before got the same decent mpg. Its not like the domestic vans which get 16/20 mpg if lucky.
Seems like a lot of extra work, just to save a few mpg. That and if you aren't a mechanic (I'm not, I'm a girl, I wouldn't have a clue how to do any of this stuff), you can't find anyone to do these mods. I'd be more interested in what things I can remove from the body itself (non mechanical) to make the car lighter, cause that seems like it helps a lot. I had that goofy spoiler removed with the plastic tracking and motors for the middle sunroof, holes filled in and spot painted, that took a lot of weight just off the roof and it looks a lot better too, as those spoiler/sunroof combos make the van look top heavy. The body shop sealed up the middle sunroof too.

[orange4boy]

I live in near vancouver BC so I rarely have to use the AC.

You have probably done all you can for weight reduction. The only other things I would suggest is the spare tire under the rear bumper and the jack and tools under the passenger seat. If you have On-star or AAA then you could risk a flat without a spare. Some people keep their gas tank low to save hauling extra gallons of gas around. Fill the back with helium balloons? Some people also remove all the carpet and panelling but that looks like crap in my opinion. I like my previa so I keep it looking good.

Some kind of fuel efficiency instrumentation can also help a lot.

It's too bad there are no ecomodding shops around. You can bet if the price of gas stays high there will be.

[Jeff]

Not to be a "one-upper" but I got 26.48 MPG in the rain, moderate traffic between Federal Way and Olympia today. The only 'mods' I have made are to air the tire up to 44 PSI and remove the two bench seats. I do make sure to go about 1mph slower than the average traffic speed, just to avoid any unnecessary braking.

To be fair though, I used two different gas stations (pre trip was Chevron and post trip was Costco). So possibly the first pump filled a little more than the second (I always let the pump go until it shuts off automatically) which may have skewed my results. Also my trip consisted of approximately 95% freeway travel.

One of these days though I'd like to try sealing over all the unnecesary seams in the body (maybe use a little tape?), and removing the luggage rack from the top of the vehicle. Or maybe try the golf ball dimple effect (seen Mythbusters lately?) except in a plastic thermoformed panel version.

[Domman56]

K&N air filter time Automatic 2 MPG at least

[AlaricD]

Originally Posted by orange4boy

1) No alternator, running on 2 deep cycle batteries.
2) Electric cooling fan
3) All accessory belts off (no p/s, a/c, fan, alt.)
4) All passenger seats out.

On my own Previa, I would probably prefer to have some sort of A/C clutch type mechanism for the alternator, so that I could engage the alternator at will. This would give the batteries a little more range (at the cost of fuel economy, but one could engage it on long downhill sections).

Do you use a battery isolator at all? It seems like you could potentially be in a lot of hurt if your batteries give up while on the road. Maybe even carrying a solar battery charger could help just a little, even though they would add some weight.

[orange4boy]

Not to be a "one-upper" but I got 26.48 MPG in the rain, moderate traffic between Federal Way and Olympia today. The only 'mods' I have made are to air the tire up to 44 PSI and remove the two bench seats. I do make sure to go about 1mph slower than the average traffic speed, just to avoid any unnecessary braking.

I guess you didn't check my fuel log. I usually get about 35 mpg on the highway driving at about 55. 90 day average is currently 27mpg. I live on a very hilly island and most of my trips are short. I used to get 15-17mpg on the island.

One upping is what ecomodder is all about. You highway mileage is darn good for a mostly stock Previa.

One of these days though I'd like to try sealing over all the unnecesary seams in the body (maybe use a little tape?), and removing the luggage rack from the top of the vehicle.

Officially referred to as basjoosing. I used foam weather stripping from home depot. Almost invisible. Comes in a bunch of sizes. Luggage rack delete - good.

[orange4boy]

On my own Previa, I would probably prefer to have some sort of A/C clutch type mechanism for the alternator, so that I could engage the alternator at will. This would give the batteries a little more range (at the cost of fuel economy, but one could engage it on long downhill sections).

The A/C clutch idea is oft talked about but I've never seen one done. Would be cool to have. Most people have gone the much simpler route of a switch to the field coils to disable it.

I have a spare battery, amp meter and voltage meter. I have run low a couple of times but only ran out once. My charger unplugged somehow during the night so I only had 30% left to get home. 120Km I had to stop at some point didn't have enough juice to restart. I would have been fine if I didn't have to shut off the van on the ferry. A nice gas station attendant let me charge up with my 25 amp charger for a while and I was on my way in about 20 minutes. Now I have a 50 amp charger so I only need half the time to get enough to get home.

Once you learn about amp hours and get used to your system it becomes just like making sure you have enough gas. I never worry anymore. Just the one accident.

[AlaricD]

Originally Posted by orange4boy

The A/C clutch idea is oft talked about but I've never seen one done. Would be cool to have. Most people have gone the much simpler route of a switch to the field coils to disable it.

That may be the more "efficient" way to do it-- the clutch system may add much more rotating mass. I guess that's getting all into the deep theoretical here, though. Still, either way it'd be nice to be able to recharge a little. It'd be interesting to have an automatic system monitoring the battery state to override and start charging.

[Burnt]

I just finished a cesarean section for previa (I'm on call today); I have to say that's one of the worst names for a car I've ever heard

Does the car look like a placenta sitting on a cervix?