(New member) How much can one optimize with no ScanGauge?

Discussion in 'Start Your Journey Here' started by Right Lane Cruiser, Apr 14, 2007.

  1. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Hello, all! I've really been enjoying reading the articles and forums at this site as well as over on greenhybrid.com -- I just added the 4.5 years of mileage data I have on my current car in the logs over the past couple of days.

    A little background... I learned to drive in a '70 semiautomatic VW bug. Since I payed for the gas I was interested in pulling as much out of it as I could. That vehicle belonged to my father and he never got much over 19mpg out of it but I regularly managed 26 with nothing more than slow starts and low speed driving. I got into the habit of filling up at the same station and at the same pump to try to normalize fill levels while driving this car, and started calculating mileage for every tank.

    When I headed off to grad school (for a year) I purchased a used '95 Hyundai Elantra (5spd MT) with 62,500 on the odometer. The car was rated for about 28 on the highway but during moderate temperature months I normally got in the 32-33mpg range. I did hit 35mpg in that car once. That one drank gas so fast with the AC on that I could actually watch the gas gauge drop as I drove and it had NO power from a stop if it was on. I got into the habit of turning off the AC to start, and started cycling it to try to keep the mileage up. I took this car with me when I moved to MN (from NC -- grew up in SC) back in 2000 and drove it until it decided to eat a wiring harness at the battery (rare shorted fuse). I had about 104K on it at that point. I got it fixed, sold it to my sister, and bought a 2002 Elantra brand new -- also 5spd MT. I figured this was my chance to break a car in right from the start. The '95 had been abused by a high schooler and I got it as a repo (had to rebuild the transmission not long after I bought it).

    I was pretty enthused when I managed to make a bit over 38mpg on a tank due to a trip to Detroit Lakes -- before the car was fully broken in, no less! That was likely due in large part to the low speed (no faster than 55 and usually no more than 50 on that trip as I had read I shouldn't go faster during break-in) -- though I did have a passenger and a trunk full of luggage weighing me down. I've been pushing for higher mileage ever since.

    Here's the rub, though. I don't have a ScanGauge and though I'd love to have one I just can't afford it at the moment. I'm getting married in 2 weeks and I've got no spare anything to spend and won't until I get everything paid off. The car is long paid off so it is just maintenance. So how much more fine tuning can I do without the feedback that gauge would give me? I've only got a tach, a speedometer, and a standard needle gas gauge, though I do have two trip odometers. I use one of those for tank mileage, and the other I've never reset and use to give 10ths on the odometer.

    Here's what I run currently:

    I use Havoline 5w-30 changed out every 3K miles. Not sure what the best synthetic would be for this car but this has worked okay so far for me.

    I run regular (87) unleaded gas. My current favorite for filling up is Costco. I fill up to the first cutoff, no more. I try to use the same pump every time.

    I rotate the tires every 6K miles. The first set was rated for 40K miles but I got 60 out of them before they needed replacing (I dislike hard driving and my tires show it I guess). I don't remember the brand of the current set but they are also rated for 40K and have a max rated pressure of 44psi -- I'm running them at 40 right now. How much higher could I go here and still be safe? I know 44 is probably where I should have them and I'm willing to fill to that level.

    I've been using engine off at long stops since 2000, but over the last year or so I've started FASing to allow unpowered coast to stoplights I'm sure won't change before I can get there.

    I've used DWB for some time to try to smooth out the speed variations caused by traffic.

    I tend to accelerate quite slowly and upshift at earliest opportunity to keep the engine at low revs. Here is where (in addition to an inability to do much with segment recording) I'm hurting most without the ScanGauge, I think. I'm not sure I'm running the engine optimally in this case. I typically upshift into 3rd at about 13mph, 4th at 21mph, and 5th at 31mph. I'll generally travel as slow as I can in the highest gear I can manage without lugging the engine. Any thoughts on improvements here? In 5th at 30mph I'm running at about 1100rpm, and at 50mph I'm just about 2100rpm. (Wish I had a tall sixth for high speed "loafing!")

    I prefer to drive about 5mph under the limit... slower if no one else is around. I camp out in the right lane usually (big surprise there, huh?) but will go faster if people can't get around me.

    Historically I've used coasting in neutral pretty heavily. Since it is a front wheel drive I put it in neutral and keep the clutch pedal depressed to get minimal friction. I'll do this anytime I need to slow down but not quickly. Recently I've been using engine braking a bit more as I then avoid using the brakes as much and I seem to have a bit more efficiency when I do this in particular circumstances but it is hard to tell when the only metrics I really have are distance on percentage of tank left and total distance on a tank. Is there some general guideline that would help me choose here, or am I mistaken about the (light) engine braking (no downshifting)?

    I did buy an engine block heater a few months back and started plugging in the car overnight to reduce the fuel hit during morning warm up. I couldn't do it before because the apartment garage didn't have an outlet -- but my house has one right in front of the car. :) Is there some temperature at which the block heater is no longer helpful in summer? (I do park in the garage -- got a three stall so I might at some future time have a more fuel-efficient car and keep this one for winter work if that might be more practical).

    Just recently (in the last couple of months or so) I've started using DWL with a significantly larger drop in speed. I saw an immediate boost that is pretty obvious in my graph over in the logs on this site. A few tanks ago I even came close to my best ever (39.7) but did it on my normal route!! :woot:

    For my current tank I've decided to try to go extreme (at least in my mind) on FAS by using that in almost every circumstance I would normally use a neutral coast. So far I've only got 96 miles on the tank but even with a bad bout of slow'n'go on the highway yesterday that caused my 40 minute commute to balloon to 1:15 I'm just barely touching the top of the full mark on the tank. For comparison, I'm normally between 70 and 80 miles when the needle touches that mark. The 39mpg tank I just pulled 3 tanks ago hit that mark at 92miles and I had pretty much perfect driving up to that point.

    Along with the FAS stuff comes a question -- where is the trade off here? In other words, at what point is the "glide" with engine off too short to make it worth it? I know this has a lot of variables to consider but I'd be grateful for any obvious hints.

    Finally, back to the title of this thread. How much more can I expect to optimize my driving for fuel economy without the wonderful instantaneous mpg readout? I see Wayne's accomplishments and I'm just blown away. Then I was scanning the mileage logs yesterday and spotted basjoos -- good grief!! That almost made me want to give up -- makes my piddling 39mpg look like a PeterBuilt!!

    This seems like a great group and I'm open to any suggestions, questions, and even derogatory comments. I'd be thrilled if I could achieve what would normally be considered (low) hybrid mileage before being able to afford a hybrid.

    Thanks for reading my (ridiculously long) first post!

  2. brucepick

    brucepick Well-Known Member

    Welcome to CleanMPG!
    Good work on your accomplishments so far!

    I can offer that I've done decently without a ScanGauge. My car is too early for one; it's an '89.

    Have a look in the articles and/or search here on tire pressure. I'm pretty sure the recommendation here is "max sidewall", in your case 44 lb. Measure with tire cold. Expect 1 psi loss per ten degrees F. so recheck if temps drop.

    My commute is 58 mi. each way and I tank up daily. This gives me fairly quick feedback on how I'm doing. I've been gradually adding new techniques to my bag of tricks, and also some new modifications to try to improve things.

    My car is EPA rated 19/24; my last tank was just over 29. I think that was somewhat atypical; it may settle back to maybe 28.5 mpg, all other factors assumed equal. MPG should improve further with warmer weather and other future improvements on my part.
  3. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Thanks for the response, Bruce! I've been watching for pressure drops due to temperature, but I'll certainly give the max pressure a try and see what happens. I'd dearly love to break the 40mpg mark!

    Sounds like your commute may be similar to mine? I drive about 60miles round trip. Most of it is highway and I drive it normally in the 50-55 range with dips for hills (of course).

  4. brucepick

    brucepick Well-Known Member

    Look into a grill block if temps are still cool in your area.
    Some searches should turn up some posts and experiences on that topic.
    If you put one in, watch your temp gauge closely especially at first.
    I think you may need to remove it in warmer weather.

    I just put one in on my own car. I left about 1/5 of the grill space open. Theres also a lower opening which is not blocked.
  5. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Does a grill block really make that much of a difference? I wasn't sure if I wanted to try that or not...

    How did you attach yours?
  6. GaryG

    GaryG Well-Known Member

    Don't do a grill block without a Scangauge to monitor coolant temp. PM me with an address and I'll send you my good working old one for free. Anyone working as hard as you to improve mileage has my respect.

    Last edited: Apr 14, 2007
  7. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Wow! That's an EXTREMELY generous offer, GaryG! :eek:

    PM on it's way.
  8. tbaleno

    tbaleno Well-Known Member

    Looks like you are pretty much doing all the right things. Don't worry about too much air in your tires, it won't be a problem. Go with max sidewall to start.
  9. worthywads

    worthywads Don't Feel Like Satan, I am to AAA

    I'm a newbie here that has an older scangauge, purchased just before the II came out, and don't know if any improvements have been made to help but there are a few serious problems that the scangauge has as follows.

    1. Scangauge I will not identify fuel cutoff during engine braking, it will show open loop mode with the engine at a high enough temperature (must vary by vehicle) which won't be reflected as 0.0 gph or infinite mpg. With significant open loop engine braking you will actually see worse scangauge MPG estimate than coasting in neutral, though in reality you are using less fuel with engine braking.

    2. During FAS scangauge will not accumulate miles traveled. For instance my commute is 9.8 miles with no FAS. With heavy FAS on my commute home yesterday Scangauge said 6.7 miles and 28.9 mpg, but I traveled actually 9.8 miles or got 43.4mpg.

    I don't know if the SG II overcomes either of these shortcomings?

    I don't know if scangauge doesn't record miles during FAS on all vehicles or just my Tacoma?

    I'm on my first tank of FASximization and it appears that I'm improving my MPG based on good old odometer and gas gauge, the scangauge isn't helping at all.

  10. basjoos

    basjoos Well-Known Member

    You can get great mileage without a Scanguage if keep a good mental model of how your engine, transmission, and the physics of automotive motion work, and you apply the many techniques mentioned on this website. I also don't have a Scanguage (or even a tach) on my Civic CX (although I finally broke down and have ordered a SuperMID which will provide both functions). Of course, my car is hardly stock anymore, since I have aero-modded it to the gills for better mileage at the interstate speeds that I normally travel at. With my car, a grill block was good for about 3 mpg.
  11. GaryG

    GaryG Well-Known Member

    My wife Rhonda just came to me and gave me a kiss for giving you that SG. She seen it on her computer also. We have been married since 1976, so we might as well stay married till for ever I guess. Hope you do the same with your new bride.

  12. diamondlarry

    diamondlarry Super MPG Man/god :D

    Sorry for being late:eek: , but welcome to CleanMPG! It sounds like you are already off to a great start. From the sound of things, it sounds like the gearing in your car is very similar to my Saturn's. I turn ~2400 rpm's at 55 mph. I'm guessing that your car has the potential to run close to or above 50 mpg with some work.

    Congratulations on your upcoming wedding! GaryG has some very wise advice for you to follow. I haven't been married as long as him yet but on Good Friday we celebrated 22 years of what I would say have been happy years. Sure there have been a few dips here and there but, just like getting good FE, a good marriage takes dedication and hard work. Good luck to you and your new bride!
  13. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    tbaleno -- thanks for the tire info! Is there ever a circumstance higher than max sidewall would be recommended? Or is that just one of those "Try it at your own risk!" type deals?

    worthywads -- Good things to know about the scangauge limitations. I'm not sure my vehicle actually implements fuel cutoff during engine braking. I've not been able to determine that so far. As long as I know what the limitations are I should be able to make VERY good use of the info. :)

    basjoos -- Those are some wild additions you've done to your car! They certainly seem to be effective. You've obviously got a great feel for this stuff -- how did you determine the optimal rates for your FASing? Do you use it for high speed pulse and glide as well?

    GaryG -- Thank you so much for your kind words and your kind offer! My fiancee was touched by your words, too.

    diamondlarry -- Never too late to chime in! 50mpg?! That seems so far out of reach right now... Boy if I could hit that I'd be :bananapowerslide: ! Any key suggestions to help me get anywhere close to that?

    Thanks also for your words about marriage. We intend to be married a long time and though she thinks I'm "weird" and tells me to "Just drive normal!", she knows I'll devote the same attention to detail, effort, and dedication to our marriage.
  14. Chuck

    Chuck just the messenger

    What I think Gary is trying to say is ScanGage gives you a precise coolant temperature - your vehicle may not until you have a crisis. My Insight's coolant gage is the same at 195F and 227F. :eek:
  15. tbaleno

    tbaleno Well-Known Member

    A lot of us run higher than max sidewall, but we prefer not to recommend it to people just starting out because the benefit isn't as great as getting all the basics down.
  16. Bruce

    Bruce cheapskate

    If you don't have a Scangauge, you could calibrate the pips on your fuel gage to get a bit more instant feedback but it takes a bit of work...Note the mileages at each pip or 1/2 pip, subtract them from your final mileage at the fillup, figure out the MPG at your fillup and use (mi)/(MPG) to find out gallons remaining at each pip. Average these figures over several tanks, and you should have a pretty good idea how much gas is at each pip. You can then use this to extrapolate MPG for a trip, especially if you use a substantial fraction of a tank in a single trip.

    If you want to maximize the mileage in a tank, you should find out your gas tank size and compare it to your fill amounts. You can use miles from the last pip (or low fuel light) and your MPG figures to figure out how much further you can safely push it. I know it's time to fill up when the engine cuts out going around a corner. :)

    Fuel gage pips should be more accurate than the SG for figuring out how much gas is actually remaining, since the SG depends on a consistent fill and consistent usage patterns. If you have an inconsistent fill and a large change in driving style from tank to tank, the SG can easily be off a gallon by the end of a tank; it's good practice to calibrate your fuel gage whether you have a SG or not.

    Wayne claims 8 seconds. I usually give it 10 to be sure.
    Last edited: Apr 15, 2007
  17. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Delta Flyer -- I couldn't stop laughing when I first spotted your avatar! :D That's a HUGE difference not to see on the gauge! I wonder why the resolution is so coarse?

    tbaleno -- Gotcha. I'll jack 'em up to the max (44) and then see about maybe getting up to 50 or so. The tires have about 24K on them now (rated for 40K) but since I got 60 out of that first set with a similar rating I'm not too concerned about tread wear. Have you noticed any accelerated wear with the higher pressures?

    On a different note, has anyone experimented with getting a custom gear ratio transmission constructed for his/her car? (Should I start another thread for this?) I'm constantly wishing for both taller gearing and one more (6th) gear on the top for high speed cruising so I could keep my rpms a bit lower. I was SERIOUSLY disappointed when I test drove a 6spd Hyundai Tiburon and found the final gear ratio was the same as a 5spd. I had just assumed all along that the 6th gear was for higher speed cruising but then discovered the only point was to keep the engine rpms to a narrower band by stuffing more gears into the same ratio range. It annoys me that the automatics come with a taller final ratio than the manuals, too...

    Along those lines, does anyone know of a car that comes/came with a 6th gear that really is another overdrive gear for high speed driving?
  18. Bruce

    Bruce cheapskate

    Chevy Corvette, at least c. 1990 when I had a summer internship with the group. Top speed was in 4th gear; 5th and 6th were to maximize FE at highway speeds...if you put it in 5th at full throttle at top speed, it'd slow down. It had a 350 V8 and would turn around 1500-1700 RPM at highway speeds.

    This appears to be the exception rather than the rule, unfortunately...apparently, most modern trannys with more speeds have closer ratios rather than a greater range. :(
  19. tbaleno

    tbaleno Well-Known Member

    Most people notice extended life and lower tread wear with higher pressures. This is contrary to what a lot of the old school people like Pat Goss of motorweek fame say. The problem is that these guys have been around for a long time and never updated their knowledge based on technology today vs 50 years ago. So, while 50 years ago inflating a tire would cause wear issues that just isn't the case today. The only issue is stopping in snow as far as safety or wear is concerned.

    I think the corvettes actually make good use of their top gear to get good highway mileage.
  20. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Bruce -- I thought about trying to calibrate gallons left on the tank but didn't get serious about it because there are wild variations (sometimes > 1/8 tank) depending upon how much I've got left due to turns. It's depressing to see the needle drop (even though I know it is temporary) when I go around right hand turn...

    tbaleno -- I wonder if that is part of the reason I got such good wear out of my first set of tires? I kept them at 36 most of their life and had them at 38 toward the end. I was told that most people only got about 20K or so out of them, but we all know how bad most people are about keeping their tires properly inflated. By the way, I believe the manufacturer wanted to have them at 32psi!!

    So has no-one had a custom built transmission installed for improved fuel economy? I've no idea how much something like that would cost but it seems it could be a worthwhile effort...

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