Saw this and thought you guys would like it ('94 Caprice wagon, 46mpg):

Vigo wrote: Trucks have it as well. Ram and F-series for sure, i am not sure about the GMs.

Cruzes, Colorado/Canyons and Silverado/Sierras, I know do.

The_Jed wrote: Another thing I like, even though I don't utilize any of the pulse-and-glide driving techniques, is that once you decide to try driving in an ecomodder-like fashion, you are driving with 100% consciousness regarding your actions. It takes you from being on autopilot on your way to work to saying, "Okay, if I stay at 25mph through this string of stop lights, instead of the posted limit of 30, I can time them so they're all green." Also you're acutely aware of braking distances and smoothness. My schedule prohibits racing 99% of the time so I make do with this sort of thing.

I teach my DE students that safe driving and efficient driving go hand in hand. Looking further up the road to anticipate changes, slowing earlier for stop lights and timing them for green, and anticipating cars slowing and turning can keep you moving avoiding unnecessary idling. Our Ford Fusion Hybrid even grows leaves on the IP as you drive better and gives an accounting of your drive. And yes it forces you to be more attentive when you are driving.

rslifkin wrote:

ProDarwin wrote: A Prius or Insight will knock down 46+mpg all day long driving it like you stole it, even with full HVAC control, etc. And they are probably no slower than a LT1 Caprice with that kind of gearing.

Off the line, no. But on a highway pull, the Caprice would eat the Prius 7 ways from Sunday (it wouldn't be any slower than stock, just in a lower gear to make up for the taller axle gears).

True. Nothing like using 2nd (in a 5spd) gear to accelerate on the highway! That gearing is insane.

I need to spend some time over there. Driving as much as I do, ecomodder may MAKE me money.

ProDarwin wrote:

flatlander937 wrote:

SVreX wrote: Hmmm... That makes me wonder why we haven't seen active grills coming from OEMs. With all the computer sensors, it seems pretty easy to create an operable shutter that triggers off the thermostat or fan circuit. Close the shutter for aero and fuel economy, open it when needed for cooling.

They're on the newer Mustangs and Focii. Pretty sure the Fusion as well?

Cruze Eco as well. Wonder if some home-made setup could be easily fabricated using pop-up headlight motors.

One of the Dodge Dart models - Aero? - has shutter grill, too.

I do find it interesting that these guys will start with some of the worst cars for this type of thing. A Prius or Insight will knock down 46+mpg all day long driving it like you stole it, even with full HVAC control, etc. And they are probably no slower than a LT1 Caprice with that kind of gearing.

It's strange how little overlap there is between hypermilers and other types of driving enthusiasts. One of the things i always enjoyed about my hybrids (im on my 4th and still own 3 of the 4) is that they get better mpg being driven quickly than many inefficient cars get while being hypermiled.

Having said that, i'm VERY intrigued by this wagon build and very curious to know how it drives and what it averages under non-hypermiling highway driving conditions. If it got 32+mpg being driven normally down the highway, i'd be more excited about it than i am by reading about how efficient it is while the engine isn't running.

There have been some fast AND efficient builds on ecomodder. Two of my favorites were a 200-something WHP civic that got 55mpg, and an 11-second DSM that got 40+ hwy mpg with an auto trans.

In reply to Vigo:

Considering they were rated at 25 highway when new, I wouldn't doubt 32 driven normally at 65mph with just the manual swap and silly tall rear end gearing, maybe just the manual swap.

Yeah, with the tall gearing, aero work, etc. it should be able to get into the 30s no problem on the highway if you're not going too fast.

Safe and efficient go hand in hand, except when you're a hyper - miler nutter who drafts semis at 18 inches.

Appleseed wrote: Safe and efficient go hand in hand, except when you're a hyper - miler nutter who drafts semis at 18 inches.

Aftermarket distance-sensing cruise control would be a really handy retrofit... "Car, please stay 50 (+/- 20) feet behind this truck. Thanks."

rslifkin wrote: Yeah, with the tall gearing, aero work, etc. it should be able to get into the 30s no problem on the highway if you're not going too fast.

"just under 1000 rpm at 55 mph." These guys do not exceed 55.

chuckles wrote: These guys do not exceed 55.

Yeah, most of them are pretty sluggish in that sense. One guy did aero-mod the heck out of a Civic specifically so that he could get good mileage while keeping up with highway traffic. IIRC, after all the work, it got the same mileage at somewhere in the 90 - 100 mph range that it did at 55 when it was stock

Appleseed wrote: Safe and efficient go hand in hand, except when you're a hyper - miler nutter who drafts semis at 18 inches.

That can save a lot of fuel. Our race team had a chevy cube Van and an open trailer with a 350. Going to Florida one trip I would pull up behind a friend's enclosed trailer until the smiley face antenna ball on our van started to move forward. It took a bit of concentration but we saved a ton of fuel. Luckily I didn't follow him home since he fell asleep and drove out onto the median and had to be winched back to the road.

Drafting definitely works. Best mpg I've ever gotten out of the Jeep was drafting a friend's horse trailer (pretty low to the road). 26 mpg at 65 mph for 160-ish miles. Started out with a full tank and it took so long to get the gauge off the full peg that I thought I broke it!

For a comparison point, with no traffic and no wind, it might see 20 mpg at 65 on a really good day.

Back around 1980 there was a guy in Seattle selling plans to increase mileage. He was getting around 50mpg if I remember right in a late 60's Chrysler Newport w/440cid and A/T. I knew someone that bought the plans and the process was very familiar. Now this only works on a car with a carburetor. He ran an extension cable from the mixture screw on the carb to inside the car and had a knob on it. Ran a coil of copper fuel line inside the top radiator hose and added an exhaust temp sensor with gage. Preheated fuel atomizes better. Upon reaching cruising speed, set the cruise control and lean out the mixture until just at the point the exhaust temp starts to rise. Sit back and enjoy the astronomical increase in mpg. Why does this sound familiar to us aircraft mechs? Because every light fixed wing (like Cessna's for example) with internal combustion engine has this setup and has since the 40's at least, maybe before that. Except they use engine oil to preheat the fuel and fuel to cool the engine oil. We still do this on turbine engines. Liquid to liquid coolers. Does it work? Yeah, if you're willing to only get that mileage at cruising speed. Would get the same crappy mileage in stop & go. Would also have to readjust the mixture when you turn off cruise before turning off the engine.

In reply to wlkelley3:

You can do the same thing today with megasquirt. A little better actually, since you can get more timing out of it (allowing you to go leaner without it running hot). As I recall this sends the NOx numbers through the roof, which is why you don't see it done to that degree in factory efi cars.

Lean burn definitely helps mpg in steady cruising. For the Jeep, I've got the O2 sensor set up as a wideband controller feeding a narrowband output to the stock ECU. Stoich point is adjusted to be 15.7:1 instead of 14.7:1, so closed loop runs leaner. After making adjustments to when it is / isn't in closed loop and fuel / timing tables, it works pretty well (although it sometimes surges a little when you're right on the transition out of closed loop under throttle). And I'd estimate it was worth about a 5% mpg gain.

that's some seriously impressive mileage. On the last tank, I got only 12 mpg in my caprice wagon with the same transmission, 2.93 gears, and 'normal' driving, mostly in the city. I guess I need to play with my tune a little more.

gearheadE30 wrote: that's some seriously impressive mileage. On the last tank, I got only 12 mpg in my caprice wagon with the same transmission, 2.93 gears, and 'normal' driving, mostly in the city. I guess I need to play with my tune a little more.

Tune will make a difference, but in the city, driving style matters more than anything. Cutting extra weight out of the car can help a lot too. The tune, aero and gearing start to matter more on country roads and on the highway where you're holding a more steady speed.

In the same vein, an auto trans is a bigger mpg penalty in the city than on the highway due to losses in the torque converter when accelerating with it unlocked. An aggressive converter lockup schedule can help a bit with that, but you'll never be able to avoid it entirely. On the highway, it should be able to stay locked up 95% of the time with a torquey V8, so the penalty compared to a manual (with an equivalent highest gear) is much smaller.

Smaller, but still huge. The fluid pumping requirements and total weight of spinning parts is huge compared to a manual.

Safe and efficient go hand in hand, except when you're a hyper - miler nutter who drafts semis at 18 inches.

Back when i used to drive my Honda Insight on long highway commutes i found that you didn't have to be very close to a semi to get the drafting advantage. What i found is that there's a point behind the trailer where air converges back together. When you hit that spot you feel the turbulence (especially in a tiny car). I found that you just have to get the front half of your car past that convergence point. This could still be way over one carlength behind the trailer, sometimes two.

I know some people complain it is unsafe, but I think that mostly comes from being WAY closer than you need to be, or just not paying attention. I know you're staring at the back of the same thing for a while but i found it fairly engaging to keep the car just where i wanted it, and as long as you have enough presence of mind to start braking before you hit the semi, being behind a semi is pretty much the safest place to be since you're guaranteed to be able to out-stop it in a normal car as long as you are paying attention.