___We are adding items as fast as we can and just haven’t had time to get the basics down for new users just yet. Sorry about that … The Glossary is a great start. Here are parts of an unfinished hypermiling article yet to be published that may help as well?
Basic Advanced Techniques
FAS = Forced Autostop: A Honda hybrid will AS (Autostop) in various scenario’s although it is very limiting to a given condition. To high a speed, to cold, not enough SoC (state of Charge), not enough speed since last AS, Defrost or A/C on except for the AH and HCH-II in specific conditions, etc. will not allow AS … Forcing an AS, aka FAS, takes these limits out of the equation. Shift to N, let the Tach stabilize, key back to IG-I (shuts down the ICE and electronics), key back to IG-II to reboot the electronics and coast to a stop or pre-determined lower speed depending on conditions. Recover by starting up ICE via key to IG-III, release to IG-II, and engage transmission with a rev match to continue on your way. Pro’s include a very noticeable increase in FE over any short distance trip and is required in a few areas of the US as well as much of Europe, ie. sitting at a stop sign for > 15 seconds or at a stop for > 5 minutes … Con’s include powerless coast, power brake assist is lost after a few uses, power steering is lost although at speed, you do not need it, is illegal in some locales, and possibly both gear reduction starter from excessive ICE starts and pre-mature wear from re-engagements of the transmission at speed.
D-FAS = Draft-Assisted FAS: When approaching a proper point to invoke a FAS, a draft target can be selected to increase the glide distance on the back side of the FAS. You have a speed of 65 mph, a draft target is up ahead doing 57 mph. You invoke FAS and glide into the distance draft, then into the close-in, fall back into the distance, and fall back away into a naked Glide. Pro’s include extending Glide distances significantly thus increasing overall FE (Fuel Economy) if performed properly. Con’s include having to use brakes if you came into the draft target too hot, a close-in draft is dangerous, and the wear issues included above.
P&G = Pulse and Glide: A technique used to increase the FE of any automobile under the right conditions significantly above your automobiles EPA city/highway. In a nutshell, it includes a FAS in many hybrid and non-hybrid automobiles to a lower target speed (some hybrid’s can be influenced into this mode of operation with the right application of multiple accelerator pedal inputs), reigniting the ICE, re-engagement of the Tranny with rev match, and re-acceleration to a higher target speed, repeat. Pro’s include maximizing FE in a low speed suburban or city environment (speed limits less then 45 mph). Con’s include lowering your overall average speed (more time to get to point B), a lot of work given the undulations depending on the type of hybrid or non-hybrid you are driving, and both gear reduction starter and pre-mature transmission wear from re-engagements at speed depending on the automobile being analyzed.
HS-P&G = High Speed P&G: The P&G technique was originally created to pull extreme FE from the HSD and eCVT equipped hybrids (Toyota’s and Ford’s) below 41 mph. The HS-P&G technique is used for many Honda hybrids and all non-hybrid’s if their transmissions can be re-engaged at speed. Instead of a 39 – 32 mph std. P&G range (just an example), you can step up the speed range to 70 – 55 mph (another simple example). Pro’s, increasing FE depending on temperature, weather, traffic, and road terrain conditions. Con’s include lower overall average speed, more work then any other technique other then the warm-up P&G, safety issues with a powerless Glide (see above), caveats in regards to different manufacturers if this is even possible or not … and when applied incorrectly, can actually lower your overall FE.
Warm up P&G = Exactly as stated. During warm up, your automobiles FE is at its absolute worst (open loop ops, high RR (rolling mechanical resistances) in colder temps). To attempt to alleviate some of the FE hit, you begin P&G’ing almost immediately but at lower and increasing speed ranges. P&G speed ranges are significantly reduced and stepped up as you arrive to higher speed arterials, state routes, and then Interstates and highways. Here is just one example as you are leaving your home via the subdivision or local street when conditions allow … A range example could include 0 – 15 mph, FAS to 10, 10 – 20 mph, FAS to 15, 15 – 30 mph, FAS to 20, 20 – 40 mph, FAS to 30, 30 – 50 mph, FAS to 40 … Again, this was just 1 example of what may be performed under a specialized local driving condition and temps until the automobiles in question is up to full temperature. Pro’s include alleviating the warm up FE hit to far above what would normally be possible and help to maintain your overall FE even though you are in effect warming up the car. Con’s include the most work of any technique posted so far, a lot of wear on a cold ICE, lengthier warm up time, and in some cases, more emissions due to the NOx spike on multiple re-ignitions. All other ICE-Off caveat’s also apply.
DWL = Driving w/ Load: Instead of relying on CC (Cruise control) to maintain speed, you rely on your I-FCD (Instantaneous Fuel Consumption Display) and accelerator pedal for those automobiles that have them to stay locked in at a given fuel economy. An example would be when climbing an overpass. Instead of holding a steady speed up, over, and down the other side, you allow speed to droop as you climb while maintaining load or FE on the ICE and climb back to initial target after the decline on the backside. Begin the overpass climb at 65 mph, drop off speed as you climb, reach 62 mph at the crest, increase speed on the decline back to 65 mph. The technique depends on elevation delta’s and traffic conditions. This can be simulated in a non I-FCD equipped Accord or other automobile by locking in the accelerator pedal when approaching the overpass. Just hold the accelerator steady into, up, over, and down the back side at the same exact angle while arriving at the same initial target speed after the overpass has been cleared. There are slight accelerator pedal changes that can maximize the technique for those with I-FCD’s but the locked down accelerator will work well for those just starting out and with a lack of an I-FCD. An even easier easy way to understand the technique is to drive like a roller coaster coasts over the peaks and through the troughs. Pro’s, increased FE over any small terrain delta with a minimum of work. Con’s. There is thought and user input involved as well as slightly lowering your overall average speed to a given Point B.
DWB = Driving w/out Brakes: In its simplest form, you drive as if you do not have brakes
If you have degraded or no brakes for whatever reason, you will increase buffers in traffic like you may never have considered previously. In heavy traffic and traffic jam conditions, this will allow you to maintain some speed before throwing away energy to heating up the pads/shoes. With larger buffers comes the ability to maintain a very slow speed while most others are in a stop and go jam. You can use this in any traffic tie up or heavy congestion. Pro’s include higher FE, less wear on the ICE and braking systems, and easier on your mental state. Con’s include drivers around may continuously fill your buffers and thus you will again back off to recreate them. It may actually tax your mental state depending on your aggressiveness.
PP = Potential Parking: When entering a parking lot of any description, seek out the highest spot in said parking area. What this encompasses is looking for the highest elevation (Potential) and usually Fas’ing to bleed off speed so you DWB into said spot. On egress, you have a downhill slope to help you accelerate in a FAS or with ICE-On thus increasing your overall average FE. Pro’s, decreased fuel consumption and usually easier egress as you are usually in the back of the mall, grocery store, whatever. Con’s, usually farther from the store entrance and thus a longer walk.
Face-Out = As described. When parked, you want your egress to be as clean as possible. Instead of ICE-On, Reverse, Brake, Drive, pull forward, you pull in to whatever parking lot, area, Face-Out. What it does is eliminate Reverse or any unintended fuel use to spin around. Some can use this technique even from their home with limited or no fuel consumption with a FAS based turn around Face-Out. If your drive allows (mine does) you are in a FAS coming into your drive, pull into the highest spot, coast back while spinning the car around 180 degrees to a slightly lower spot. You are now Face-Out for your next days or drives egress. Even if you do not FAS, it is best to spin your car around when it is already warmed up then in the morning from dead cold. Your fuel consumption at dead cold is much higher then when warm. Pro’s, lower fuel consumption. Con’s, have to be careful that someone would not pull in behind and limit your ability to load your trunk. Higher fuel consumption if used with a FAS incorrectly.
RR = Ridge Riding. In inclement weather, you ride the center and white line edges to alleviate some of the drag caused during rain and/or wet conditions. In most cases during rain, the center crown or ridge will have the least depth of water to plow though as will the right or left edges of your lane. You can see the changing depths ahead and adjust your track as conditions change/allow. You want to ride the ridges whenever conditions make it imperative to do so. In the snow, you will generally want to ride the most traveled tracks as they may be clear of snow, slush, water vs. riding the lanes with a snow cover or accumulation. Pros, maximizes FE in the worst conditions. Con’s, requires quite a bit of concentration to maintain the wheels within a tight area of roadway.
___There are a few more but this should get you started …
___Slowing down is your first priority to maximizing your HCH-II’s FE. Setup may be the second with the specialized techniques making the EPA ratings look downright paltry by comparison to what your car is actually worth.
___Here is an initial setup guide … Also yet to be published
Tire pressures are a very important key to higher fuel economy. The higher the pressure, the lower the rolling resistance, the higher the fuel economy. The absolute minimum you should use is the drivers side door or owners manual recommended tire inflation criteria. This is what the EPA and your car manufacturer sets tire pressures to during the EPA city/highway testing. MAX sidewall is what I would recommend for most as it is well within the safety limits of your car and tire and allows better FE then the pressure listed in the driver’s side door. I can discuss but cannot personally recommend upwards of 25% higher then MAX sidewall as there are legal constraints we all have to live with. That being said, 50 + #’s leads to even higher FE. Pro’s, higher FE, lower tread wear, more even treadwear across the treads width, shorter braking distances in a variety of conditions, and in many cases, even better handling. Con’s, higher NVH (Noise, Vibration, Harshness).
Oil types and amounts are another important key to higher FE. A proper amount of a low kinematic viscosity oil can do wonders for not only longevity of your ICE but the FE your automobile may be capable of. You should use a viscosity oil that is within the band of your automobiles lubrication requirements. That being said, not all oils are the same. If your automobile allows a 5W-20, you should be OK using a high quality Synthetic 0W-20. Mobil1 0W-20 has the lowest kinematic viscosity as well as superior wear and breakdown properties vs. ANY non-synthetic I know of. About that level … I recommend that instead of filling the case up to the high level mark that you instead use just enough oil to bring the level up to between the high and low marks. You lose capacity in case of a leak and have a very slight increase in oil temps but gain a slight amount of FE with a slightly lowered strain on the ICE’s frictional components.
Actual Post was done by xcel, Added now by Tiger: 4/25/2006 5:18 PM