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I've been doing a lot of reading about hypermiling and decided to see what I could get out of my '95 Civic DX (Sedan, MT). I was wondering if anyone had any tips or techniques specifically for my car (so I can get optimal mileage).

First off, I don't have a ScanGuage, and I don't have the money for one either. Second, I'm not planning on taking this to the extreme (I'm not planning on trying to reach 50-60 mpg).

Suggestions are great, but I do have a few questions I'd like to specifically address:

1. Does anyone know the optimal speeds to shift (I have no tachometer)?
2. What is the optimal speed of the car (I've heard different speeds in different cars, ranging from 40-60mph)?
3. Indiana weather can get really hot and humid. My hair is also longer and gets in my face/eyes with the windows down (depending on my speed...it's annoying and definitely NOT safe). That, and I usually have others in my car. I want them to be comfortable. Is it ok to have the AC on if it is just too hot? If so, how much of a difference does it make leaving it on a lower setting compared to max?
4. I'm also into car audio, so I have the typical stuff: Nice component speakers in front, no rear speakers, one 12" sub (in 1 cu ft enclosure) and two amps (not too big). Overall, I'm drawing maybe 500 watts RMS while using my system. Outside of weight, does listening to music have any affect on your mileage? There's no way I'm getting rid of it or not using it. I'll compromise my MPG if I have to for it. I'm just curious how much it might do.
5. It is better to shift into neutral with P&G due to how much farther you can travel like that, correct?

1. Most people shift around 2100
2. Optimal speed would probably be in the 45 range
3. I keep my cars blower/fan on max in hot weather and cycle the a/c on and off while using the recirculate function.
4. A large sound system will obviously use your battery and that energy will have to be replaced by the alternator/gas. Things like your car's fan don't bother this much but I don't know about amplified audio. There are some music related threads on here.
5. Correct, unless you are coming to a complete stop, then it may be better to leave it in gear. This depends on whether or not your car has a fuel cut. You can try to test this by letting off the gas while keeping your car in gear, as your car decelerates, see if you can notice a "bump" somewhere roughly around 15mph (this would be your fuel kicking back in.)
This type of situation is also one where you can get a few moments of "free A/C" by allowing your a/c compressor to help slow the car instead of braking (all assuming that the car does in fact have a fuel-cut function. :)
Hope this helps!

^ he's on the right track.

Try to anticipate conditions ahead of you. WAY ahead. You're hauling more weight, so each use of the brakes or gas pedal will cost you even more than normal. Try to time lights and roll through the green instead of stopping. Even 5mph is better than a full stop.

It looks like your gear ratios are the same as mine, so
1st gear max 30mph
2nd - 60mph
3rd - 90mph
4th - 120 :p
5th - 150 :p:D yeah right! :rolleyes:

Redline is 6900 rpm for me, so 2000 rpm is about 1/3 of each of those points. That's shifting at 10, 20, 30 and 40.

I try to shift earlier than that. I typically shift somewhere around 5, 10, 20 and 35. You're not going to get lightning acceleration, but you'll get better mileage.

EDIT: Darn, ninja'd again! Yeah, what Andrew said as well!

Note that a 95 will not have the OBD-2 port, so it cannot use an SG at all. :(

1- I take it you're looking for road speeds for shifting, yes? I can take a guess--my Si has shorter gearing than the DXes do, but it seems to like slightly higher RPMs, so I am going to guesstimate that those things roughly cancel each other out. So, when doing a "pulse":
1->2 @ 10 MPH (or less)
2->3 @ 20 MPH
3->4 @ 30 MPH
4->5 @ 40 MPH
My Si is at 2500 RPM (+ or - a very little) in the lower gear at those speeds.

2- If you can run at 40 or 45 in 5th gear on a given road, that should be close to optimal.

3- There is no benefit from using the AC at a warmer setting than full cold. As phatalbert said, leave it on full-cold and manually cycle the compressor (that is, hit the A/C button until the car gets "cold enough", then hit it again until the car gets "too warm", and repeat). I found a 5+ MPG hit from using AC in my car.

4- The weight is probably the largest effect. I'd be surprised if you even took a 10% hit on FE from a full 500W full-time draw, and music is much more dynamic than that.

5- Yes, as phatalbert said.

-soD

Ok, it looks like I've been shifting properly for the past year or so then (5, 20, 30, 40).

I'll have to try cycling the AC on and off. But do you lose any more mileage by putting the blower on max as opposed to a middle setting (not the temp setting)?

I figured my audio system (and the weight of it) would make a difference. I doubt it's 10%, though. My MPG hasn't really dropped since before I had it all installed.

Currently I'm really working on P&G, or just coasting as much as possible. That and really watching/thinking ahead to avoid having to stop.

Usually every other day I drive out to my girlfriend's house. It's about 10 miles away from my place and is mostly highway driving. The speed limit is 55mph, though most people drive 60-65mph (which I normally did too). Driving 45mph could potentially be dangerous on that highway given how people drive on it (only two lanes total as well). I think the slowest I'd feel comfortable and safe driving would be the actual 55mph limit.

The rest of my driving is all in town, but mostly just to work and back. Thankfully I have minimal stops and mostly straight, flat driving to and from work (maybe 2-3 miles?). I do that 5 days a week...none of my other driving follows any sort of pattern. I may drive on the interstate once every two weeks or so (usually 25-30 miles to where I'm going). Our speed limit on that is 70mph...and once again, people driving on it would make me feel unsafe going below that.

Remember, I'm not going for anything extreme. I'm just trying to plan ahead how I should drive based on where I'm going (and when) and my specific car.

:D sorry dave. But you do add some good points there.

You do lose a tiny bit by putting the blower on max, but you're saving by running the compressor less. The compressor uses WAY more than the blower does.

Have you pumped up your tires? That'll make a difference without any technique. I'd recommend the sidewall max - usually 44 psi.

I haven't had the chance to pump them up that much yet. I likely will eventually, but my dad swears it's worse for the tires and my safety despite whatever anyone may say or show him. I just hope he won't find out if I do.

I also don't want my ride to become uncomfortable with the tires being inflated that much...

I haven't had the chance to pump them up that much yet. I likely will eventually, but my dad swears it's worse for the tires and my safety despite whatever anyone may say or show him. I just hope he won't find out if I do.

I also don't want my ride to become uncomfortable with the tires being inflated that much...

From my experience it's not uncomfortable at all. I have mine at the rated 51psi and have no comfort issue. Tires being pumped up to max causing a safety issue would have tire manufacturers in a bunch of law suits...otherwise the tires would be max rated at about 75% of what they are. Essentially, I'm saying that if the tires were unsafe at max sidewall, then the max sidewall wouldn't be that high.

Just to get things straight, with P&G, is it better to have a quicker/faster pulse (within reason) than a slower/longer one?

Oh yes hans, you pulse at 3/4 gas pedal press or 75% throttle pressure. No wimpy acceleration when you pulse and glide. You pulse pretty hard , then glide either with your engine on or off.

Oh yes hans, you pulse at 3/4 gas pedal press or 75% throttle pressure. No wimpy acceleration when you pulse and glide. You pulse pretty hard , then glide either with your engine on or off.

On a '95 Civic DX shifting around 2000rpm? :D

No wimpy throttle pressure, then. :p Yeah, the acceleration won't be anything amazing.

Read the BSFC article in my signature for some technical stuff.

What about when you have to dive over the 50-60mph range...I tried P&G there, but my gliding wasn't very long compared to the pulse. Air resistance and friction seem to make it almost pointless. In town, going under 45mph, I can glide/coast for quite a long time, so I know I'm doing that part right.

Considering the Civic can't do a very good pulse on faster highway speeds, and it gets dragged down easily by the air resistance/friction, is it better to just keep a consistent (but not too quick) speed?

Steady speed at 65 gives me about 45mpg. P&G 50-65 mph gives me 63-66 mpg. I did one highway run at 45-60 P&G and got 75mpg, but that was in ideal conditions - 75F and a tailwind.

The real problem isn't so much the air resistance, it's the RPM. 2500 rpm at 55mph, and 3000 at 65mph. 2500 is really the limit of good mileage. P&G helps overcome that.