Best engine for a hypermiler Z

[seanof30306]

For the past year, or so, I've been working at rechanneling my aggressive instincts away from going fast and towards economy. Surprisingly, it's worked, at least, for me.

 

Going slower, relearning how to drive, etc. drove me crazy, at first, but once I learned the techniques of hypermiling, it actually got interesting as i worked to do better and better at it. In order to hypermile, you have to be a lot more engaged in the process of driving; you can't just crank up the stereo and kick back anymore.

 

In my Jeep Cherokee daily driver, I've gone from 15-16 mpg to 22-23 mpg simply by changing the way I drive. That's not a lot, but I think it's pretty good for a 3900lb brick.

 

In recent months, I've begun riding my old Kawasaki KZ650 as a daily rider. Applying hypermiling techniques has taken me from 34-35 mpg to 47-48 mpg.

 

I've been planning on selling my '89 Firebird toy for awhile and replacing it with a 240Z for some time. I've always loved the way they look, and I fit better in a Z than any other sports car (6'5", 260). I'd originally thought about an LSX swap, but, I've recently realized it'd make a great hypermiler candidate, too. It's light, it's aerodynamic, it has manual steering and brakes, and there's plenty of room under the hood for any engine I'd want to swap in.

 

I'm thinking I'd want to swap in a non-turbo, 4 cyl gas engine with at least a 5 speed transmission (preferrably a 6 speed). Obviously, fuel injection would be preferrable, but I've run into problems with the PCM from hypermiling my Jeep, I think it's related to engine-off coasting and the VSS.

 

I'm just wondering if anyone else has thought or done anything along these lines.

[TrumpetRhapsody]

Are you just talking about just doing the speed limit and attempting to minimize acceleration to use less gas? I've never heard of "hypermiling".

[aziza z]

Are you just talking about just doing the speed limit and attempting to minimize acceleration to use less gas? I've never heard of "hypermiling".

 

http://www.google.com/search?hl=en&defl=en&q=define:Hypermiling&sa=X&oi=glossary_definition&ct=title

[Daeron]

I and my family have thought about it a great deal, for many many years. The easiest route depends on your definition of easy.. an old 2 liter roadster engine and bellhousing would bolt straight on to an early 240 transmission with the bellhousing removed, and you would simply have to figure out motor mounts and fuel injection.. or you could swap in the engine and trans from an s13 240SX or even an older, RWD 200SX.

 

Surprisingly, the aerodynamics of this vehicle are NOT the greatest.. but can be VASTLY improved with some work. See the Aerodynamics sub-forum for more details (You *might* still need to PM an admin for an invite into that sub-forum if it doesn't show up automatically)

 

If you REALLY want to make a SUPER cool high-mileage daily-driver, the S30 is a decent chassis to start with. Have you checked out the eco-modder forum yet? I am not sure what the URL is but a google search of the term I typed should bring it up.

 

If you do get into this, please post a project thread!! I would love to see what kind of results you attain.

[cygnusx1]

That's funny, I am doing a hypermile experiment with my 2002 WRX right now. It took all my energy to NOT challenge an IS300 in the twisties this morning. He came flying up on my rear bumper and I know what he wanted. I bit my tongue and kept the boost gauge in the vacuum zone.

 

I am just shifting at 2500, using half throttle at most, and cruising in the highest gear possible. I want to see how much gas I can save. I drive a total of 65 miles per day.

 

Back in the 90's I drove a 1990 Civic Hatch (rare sub base model) This car was STRIPPED. It had 60hp at the crank but it got 39 to 41mpg regularly. It was the Civic hatch with black plastic bumpers, one speaker, manual windows, no rear wiper, no intermittent wipers, no center console and what looked like a 1/4" tailpipe!

 

The 1984 200SX 4 cylinders were really good on gas too. I drove one 7500 miles in 15 days on a little road trip and got around 37mpg.

[seanof30306]

That's funny, I am doing a hypermile experiment with my 2002 WRX right now. It took all my energy to NOT challenge an IS300 in the twisties this morning. He came flying up on my rear bumper and I know what he wanted. I bit my tongue and kept the boost gauge in the vacuum zone.

 

I am just shifting at 2500, using half throttle at most, and cruising in the highest gear possible. I want to see how much gas I can save. I drive a total of 65 miles per day.

 

Back in the 90's I drove a 1990 Civic Hatch (rare sub base model) This car was STRIPPED. It had 60hp at the crank but it got 39 to 41mpg regularly. It was the Civic hatch with black plastic bumpers, one speaker, manual windows, no rear wiper, no intermittent wipers, no center console and what looked like a 1/4" tailpipe!

 

The 1984 200SX 4 cylinders were really good on gas too. I drove one 7500 miles in 15 days on a little road trip and got around 37mpg.

 

 

I really like fuel injection for the mpg and reliability, but am a little afraid of it for hypermiling.

 

One of the techniques they use is called "auto-stop", where you coast with the engine off. One of the reasons I like the S30 is no power brakes or power steering, which lets you auto-stop safely.

 

As I was studying the different techniques, I experimented on my Jeep Cherokee. On my way in to work, there a downhill that runs for almost a mile and a half, right into the highway exit. I found that I could crest the hill, throw it into neutral and shut it off and coast all the way to the light, shedding only 5mph or so before getting to the exit.

 

Soon after I started doing it, though I started having problems with the Jeep. Under normal highway driving, the converter would intermittently lock and unlock. Also, while it starts perfectly when cold, if it's been running even a few minutes, and you shut it off, it won't restart unless you floor the gas. Kinda kills the whole idea of coasting.

 

I reset the PCM, and the problem with the converter cleared right up. Haven't solved the restart problem, though, and no one on the Jeep Cherokee forum or the Hypermiling forum I'm on has any clue. It's made me wary of hypermiling a car with a VSS, which is the only thing I can figure auto-stopping would affect.

 

Here's the clean mpg forum, if anyone's interested.

 

http://www.cleanmpg.com/cmps_index.php

 

Over the past few months, I've transitioned to my '79 Kawasaki KZ650 as daily transportation. It got 36-37 mpg, but, using hypermiling techniques, I've been getting 44-45, and the jetting is still too rich; there's a lot more there.

 

Oh, and on your hypermiling experiment? The biggest gains I've seen came from simply slowing down. I normally drove 75-80 on the highway. it took some work, but I've managed to slow it down to 60. You never realize how many crazy people there are on the road till you quit passing them.

 

Last summer, I had to make a 206 mile round trip several times in the same week. I decided to run it late at night, and to set the cruise on a specific speed each time and leave it there. Here's what i got.

 

50 mph: 25.21

55 mph: 23.89

60 mph: 22.46

65 mph: 21.33

70 mph: 18.87

 

The next biggest gains came from retraining to eliminate jackrabbit starts, and shutting it off at stoplights, drive-throughs, etc.

[cygnusx1]

I've seen the show that featured a hypermiler. Some of his techniques were too dangerous IMHO. I just want to correct your statement above.

 

The S30 does have power brakes. They are vacuum assist and will lose vacuum after one or two pumps with the engine off.

 

It's not worth saving $15 on a tank to endanger lives. Be careful. Instead of using weird driving techniques, focus on picking an efficient engine, and get a custom programmable fuel injection system onboard. Then spend your energy programming the engine management to run as lean as possible. Maybe incorporate a "lean switch" or even shut down cylinders with a fancy valve opening mechanism. Similar to what some of the automakers are doing.

[seanof30306]

I've seen the show that featured a hypermiler. Some of his techniques were too dangerous IMHO. I just want to correct your statement above.

 

The S30 does have power brakes. They are vacuum assist and will lose vacuum after one or two pumps with the engine off.

 

It's not worth saving $15 on a tank to endanger lives. Be careful. Instead of using weird driving techniques, focus on picking an efficient engine, and get a custom programmable fuel injection system onboard. Then spend your energy programming the engine management to run as lean as possible. Maybe incorporate a "lean switch" or even shut down cylinders with a fancy valve opening mechanism. Similar to what some of the automakers are doing.

 

I agree on the brakes. On a non-power brake/power-steering car, though, there's nothing at all wrong or dangerous with the auto-stop technique. I do it all the time on my bike and it is 100% safe.

 

As far as lean-tuning, that can get very dangerous. You can lean an engine well past Stoich, and it'll run great on a flat road, but run into even a slight uphill, or romp on the gas by accident or in an emergency, and you can find yourself with catastrophic detonation.

 

I've been fooling around with my GM TBI Firebird for a number of years. The forum I belong to has an avid group of tuners who have long-since hacked the ECM's and began burning their own chips. In the past several years, we've moved beyond chip burning to emulators, wideband, and on the fly tuning. My TBI originally had 3 fuel maps; it now has 24, and more timing tables than you can shake a stick at. Recently, a couple of guys have gotten greedy, taking their "economy modes" into the stratosphere, and they've done a lot of damage. Even though they have multiple tables, those 20 year old OBD1 ecm's just aren't agile enough to react in time when you rolling along at 19:1 and hit a hill.

[cygnusx1]

I watched a hypermiler run through a rest area at 50+ mph to avoid stopping in traffic. He had no intention of touching his brake pedal and almost t-boned an unsuspecting driver in the rest area. That's what I mean by unsafe. Most engines can tolerate running leaner than they are set from the factory. If you find a spot where the engine can run extra lean and still run well, you can tune that in and drive in that zone. I'm not talking about running 20:1 or anything. Just a bit leaner than stoich. There is a point where you can go overboard. Obviously, the trick is to get it right and keep it there. The tough part is avoiding "tweaking" disease and going too far. I know I've been there. Me, I am going to do what the Europeans have been doing for decades, drive smaller, lighter, low displacement vehicles. My next DD is going to be SMALL. I am only afraid of the "other" people driving the giant SUV's.

 

Here is a list of typical cars you can rent in Italy where gas is around $10/gallon.

 

Vehicles found in the Economy class typically include the Fiat Punto, Opel Corsa, Volkswagen Polo o similar, all with a/c, stereo, airbag on the driver side.

 

Compact

Vehicles found in the Compact class typically include the Alfa Romeo 147, Ford Focus, Volkswagen Golf o similar.

 

Intermediate

Vehicles found in the Intermediate class typically include the Alfa Romeo 156, Citroen Xsara Picasso, Volvo V40, or similar.

 

Standard

Vehicles found in the Standard class typically include the Volvo S60 or similar.

 

 

There is no Best. For mileage, smaller, lighter, more modern, is better.

 

 

Fiat Punto = 60mpg.

http://www.usedcarexpert.co.uk/reviews/Fiat_Punto_Review_200

[johnc]

Hypermiler? Hypermilling? Did someone just invent a fancy term to describe driving like an old lady?

[seanof30306]

Hypermiler? Hypermilling? Did someone just invent a fancy term to describe driving like an old lady?

 

The higher gas goes, the younger and hotter that little old lady seems.

[seanof30306]

I watched a hypermiler run through a rest area at 50+ mph to avoid stopping in traffic. He had no intention of touching his brake pedal and almost t-boned an unsuspecting driver in the rest area. That's what I mean by unsafe. Most engines can tolerate running leaner than they are set from the factory. If you find a spot where the engine can run extra lean and still run well, you can tune that in and drive in that zone. I'm not talking about running 20:1 or anything. Just a bit leaner than stoich. There is a point where you can go overboard. Obviously, the trick is to get it right and keep it there. The tough part is avoiding "tweaking" disease and going too far. I know I've been there. Me, I am going to do what the Europeans have been doing for decades, drive smaller, lighter, low displacement vehicles. My next DD is going to be SMALL. I am only afraid of the "other" people driving the giant SUV's.

 

Here is a list of typical cars you can rent in Italy where gas is around $10/gallon.

 

Vehicles found in the Economy class typically include the Fiat Punto, Opel Corsa, Volkswagen Polo o similar, all with a/c, stereo, airbag on the driver side.

 

Compact

Vehicles found in the Compact class typically include the Alfa Romeo 147, Ford Focus, Volkswagen Golf o similar.

 

Intermediate

Vehicles found in the Intermediate class typically include the Alfa Romeo 156, Citroen Xsara Picasso, Volvo V40, or similar.

 

Standard

Vehicles found in the Standard class typically include the Volvo S60 or similar.

 

 

There is no Best. For mileage, smaller, lighter, more modern, is better.

 

 

Fiat Punto = 60mpg.

http://www.usedcarexpert.co.uk/reviews/Fiat_Punto_Review_200

 

Here's the thing ... why can't someone make one of those econoboxes look cool? They's sell a lot more of them over here if they didn't look like dorkmobiles.

 

A buddy of mine is obsessed with the Smart Car. I think it's a pretty good idea, except it gets 20mpg less than it should, for what you give up. 40mpg, for that? Give me a break.

 

I'll take my old CRX HF .... 50 mpg all day long.

 

What I'm trying to do here is take my project car, and instead of striving for max hp/tire frying/little old lady scaring, striving for mpg. My daily rider will be a motorcycle, and I'll keep my jeep till the wheels fall off. This is just the thing I tinker with.

[cygnusx1]

Beauty is in the eye of the beholder.

 

Johnc, here is a video showing proper hypermiling techniques.

 

[johnc]

BMW did a lot of research in the early 1980s regarding proper engine design and driving technique for max fuel economy. A lot of that research is appropriate to this discussion.

 

Some of their findings:

 

1. Reducing engine rpm increases fuel economy via the reduction of friction losses.

2. Increasing throttle opening reduces pumping losses which increases fuel economy.

3. Steady state cruise can go as lean as 20 to 1 with proper engine management.

4. Gearing has a significant affect on fuel economy.

 

The result of these findings was the Eta engine series. They were designed to produce good low end torque, had internal friction reductions (light valve springs and oil ring tension, etc.), and had specially designed ECUs that went real lean at cruise.

 

Gearing was tall and the dash upshift light was programmed to get the driver into 5th or top gear as quickly as possible. The throttle control was also non-linear so the driver got larger throttle openings then normal with any resulting surge controlled through the ECU.

[Daeron]

another thing to point out is that many, if not most OE fuel injection systems cut injector output entirely at zero throttle. Take your foot off the gas, and no fuel is being injected whatsoever. (below a certain RPM, usually around 4 grand) In other words, if you see a red light ahead that you know will be green soon enough, and let off the gas 1/4 mile away and AVOID hitting the brake, approaching the red light at 20 mph as it turns green, you are using the least possible amount of gas.

 

 

It IS amazing how much more effort it takes to drive for efficiency than it does for power/performance. I deliver pizzas in a town on the outskirts of our baby metropolis down here, and and 3/4 of my delivery area is a large, essentially rural area. I have up to 12 miles one way that I can drive into that turf, and more than once I have forgotten to get gasoline as I was leaving the store. 20 miles later, when I am still 5-8 miles out, I realize that I am in dire straits, and once or twice I HAVE actually run out of gas.. but three or four times I've made this mistake and just cut the radio, and ignored everything else but driving with as steady and light a throttle foot as possible. Believe me, it feels almost like I am in a fighter plane over enemy territory with a fuel leak, because it is MORTIFYING to call work and have them send someone with a gallon in a can to me.

 

 

IMHO, CRX HF is the BEST car to tinker with for ecomodding. The shape of the car is already SO close to ideal, that with minor work making a boat-tail on the back, and cleaning up a few body lines, you can easily get up over 50mpg as you already mentioned. Installing an engine and EMS specifically designed for economy? Well, Honda already did that, but its GOTTA be able to be improved upon.

[johnc]

It IS amazing how much more effort it takes to drive for efficiency than it does for power/performance.

 

You've never driven on a race track at 10/10ths for 45 minutes. Get your competition license and do a Spec Racer Ford rental at the next local SCCA event or rent a shifter kart and run a 30 minute heat race.

[cygnusx1]

I started hypermiling my WRX last week and quit today.

 

Normally I drive like a bat out of hell, on boost, passing and cruising at 5000rpms just to hear the boxer. I get around 23mpg. This past tank I went easy, low revs, no passing, no racing....I grannied over to the gas station at lunch time and got 25.3mpg. Screw it. I'm going back to lead foot. Look out!

[Nick56289]

I agree on the brakes. On a non-power brake/power-steering car, though, there's nothing at all wrong or dangerous with the auto-stop technique. I do it all the time on my bike and it is 100% safe.

 

Id just like to say that turning of your bikes engine while you are still riding it so that you can coast is extremely dangerous and no one should ever do it. Bikes need to be able to accelerate to remain stable and it is especially important to be able to roll on the throttle to put weight on the rear wheel in a turn. If you needed to get out of the way of a car or turn quickly you would be in a world of hurt. Proper throttle control and steering will get you out of more situations than the brakes in a car, but this is 10x more true on a bike. I doubt the safety of doing this in a car, but doing it on a bike is a recipe for disaster.

 

 

Sorry I had to chime in on the safety issue here. Ive been riding a long time so ask me how I know. I agree that driving techniques are a huge factor in obtaining good fuel economy but you should not sacrifice safety. Focus instead on aerodynamics, weight, and a good engine choice.

[naviathan]

I started hypermiling my WRX last week and quit today.

 

Normally I drive like a bat out of hell, on boost, passing and cruising at 5000rpms just to hear the boxer. I get around 23mpg. This past tank I went easy, low revs, no passing, no racing....I grannied over to the gas station at lunch time and got 25.3mpg. Screw it. I'm going back to lead foot. Look out!

Yeah for all 2.3 extra mpg I'd rather have fun when I drive.

I bought the wife a 2004 Suzuki Forenza for a good gas mileage little mommy car. We got 27.5mpg on the first tank and that wasn't babying the car. And it needs a MAP sensor. Gotta go pick one up from the dealer...Damned Suzuki, everything is dealer only except the O2?!?! Anyhow, for $5500 I can play with my Zs and my Ranger and still have the wife's for good gas mileage.

[Pete84]

Do you have any idea how your A/F's are?

 

I remember reading an comparison several tuner cars, and a WRX by Crawford Performance had a specific tune for mileage that really lowered the A/F's, but a bit far, think they said there was some white some. . .

Perhaps a special burn to help out with the mileage?