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Greetings. I've been reading all I can on the forums. Great information....thanks to all who have contributed. I have a few questions that are Ford Focus-specific. Hopefully some FoFo drivers are reading.

1. What are your suggested shifting RPMs (pretty much all flat driving)

2. The max sidewall pressure on my tires is 44 psi. These are 16" low-profile tires-will over-inflation to that pressure cause excessive wear?

3. This is the fastest-warming vehicle I've ever owned (reaches operating temp. within a mile, unless it's extremely cold)....is radiator blocking necessary/desirable (mild NC winters and all...)?

4. What is the most efficient 5th gear speed?

5. Will pulse & glide help me, esp. with such short, low speed trips?

6. Will FAS help, or is it more trouble than it's worth (no power brakes/steering)?

Most of my driving is short (<5 mi.) trips at speeds <45 mph. I thought I was a pretty gentle driver, but when I see some of the numbers on here...WHOA!!

Thanks for your help!

ME

Welcome, Menglish! I can't help you with your Focus-specific questions, but I'm curious: Whereabouts in eastern NC are you? Anywhere near the Outer Banks?

Greetings, Menglish! Welcome to CleanMPG. :)

You have some excellent questions -- let's see if we can address them. ;)

Be sure to read the articles on the front page first (Particularly Beating the EPA - The Why’s and how to Hypermile. (http://www.cleanmpg.com/forums/showthread.php?t=1510)), then we can look at your questions below:

Shifting RPM will depend upon the engine torque, the engine temperature, the load (terrain and desired acceleration), traffic conditions (which determine speed and acceleration profiles), road conditions (dry, wet, snowy/icy), and weather (wind, rain?). Generally speaking however you will want to keep your shifts at no more than 2k RPM. As long as you aren't lugging the engine, shifting at lower RPM can be better. In my car (with a 2.0l 4cyl car) I typically shift to 2nd as soon as the car is rolling about 3mph, 3rd at just over 10mph, 4th at 20mph, and 5th at about 26mph. That is with gentle acceleration that is intended to keep going to something higher than 45mph when I've got plenty of time to accelerate. Otherwise, I'm getting ready to P&G and I'll extend the RPM a little higher and then hang onto 4th until I hit 45mph -- then cut the engine off for a glide.

As long as the wheels are balanced and aligned properly you will experience BETTER wear characteristics at higher pressures. Your ride will be harsher, but handling will be substantially "sportier" than before. Cornering is better, stopping distances are better, grip is better, and rolling resistance is reduced so you'll see very nice improvements in FE. Because of the steel belt construction in today's radial tires you cannot cause them to "bulge" in the middle of the tread. The edges will lift up ever so slightly and the sidewalls will become more nearly flat. We do recommend you keep those tire pressures up to max sidewall because of these characteristics and recommend that you keep a close eye on them so that they stay that way. Temperature variations can cause pretty decent swings in tire pressure. Several of us range higher than max pressure and though we cannot legally endorse such a practice I can tell you that the benefits continue to improve as pressure rises -- and also that burst pressure for a tire in good physical condition (no nicks, etc) is somewhere in the neighborhood of 200psi. Slight (open to interpretation! ;)) overinflation is not anywhere near as dangerous as the general public believes. There is some excellent information about tire inflation in the articles on the home page of this site.

Radiator blocking can make a significant difference at the temperatures you are seeing. I started blocking mine when the temps got down into the 50s, but you do need to monitor engine temperature closely to be sure you don't have an issue with overheating. The ScanGauge is an excellent tool for this and I wouldn't recommend blocking at higher temperatures unless you have something like it to monitor the temps carefully. At winter temps, it shouldn't be an issue. I know that Blake (who lives close to Cary, NC) has had his block in place for a while now and it is helping him quite a bit.

Generally speaking the most efficient speed for the average car is around 40mph. This is when the engine is running fast enough to be efficient and wind resistance is low enough to balance out. Wind will alter this speed a bit, but 40mph is a great speed to target.

You bet P&G will help for shorter trips! I couldn't manage my numbers without doing that for EVERY trip I take. The more you can glide the better.

FAS is definitely worth it but you should be very careful to practice any new techniques -- particularly this one! -- should be practiced extensively where there is NO traffic so that you can learn exactly what the car will do when the engine is off. Power steering will be gone, but your brakes will depend upon stored vacuum for about 4 good pumps. I recommend finding an isolated area and run the vacuum out so you can find out what unassisted braking is like. It takes a lot more effort but it is doable. Typically you can extend the vacuum by just using gentle constant pressure. Constant pressure won't use up the vacuum so you can brake longer -- it is the cycles of braking that use it. If you run out, just restart the car. Also, whenever possible you should be bump starting the car at speed. This is faster and more efficient than key starting and won't impact your battery.

In warm weather I'm pretty sure that I could startle the heck out of you with mileage for the right kind of short trip. If there are a minimum of stops and traffic and agreeable terrain, you can really pull some astonishing numbers.

Once again, welcome! Keep asking questions and we'll do our best to help you improve your FE. :)

Hi and welcome to Cleanmpg!

Just to reiterate what Sean was saying, go ahead and pump those tires up. I'm running at 60 psi in my tires that have a max sidewall rating of 51. No issues at all.

Also, Being in the same area as you, I can say that I've been running with a 50% block of my radiator anytime the daytime highs are less than 75 degrees. I have a scangauge so I can monitor my coolant temps and the max temp my coolant gets to is 198 degrees, reguardless of if its 30 degrees outside or 75 degrees. That tells me that I can run more of a block in the wintertime without any side effects, but that blocking percentage is really based off your car. If I were you I'd get a scangauge because its a great tool for tracking instantaneous FE as well as tank averages and would allow you to keep track of coolant temps.

Since its cold here in NC right now, I'd say it would be completely safe to run at least a 50% block with no issues, but you definitely would want some way of monitoring temps if you want to run one in the summer or have more of a block.


As for FASing... You brakes are hydraulic and should have plenty of reserve leftover when you turn your car off for 3-4 applications of the brake. Steering at speed also isn't an issue because power steering is really only needed at really slow speeds ( < 5 mph).

Make sure you keep an eye on your battery voltages if you are FASing at night because headlights can considerably drain your battery down.

Another thing you can do is use the A/C sparingly, if at all. Although this isn't an issue right now since its winter time, during the summer it really helps once you get your car cool, to just turn on the vent and recirculate the air inside the car until it gets too warm for you. I know I went all last summer without using my A/C at all in my car. Getting your windows tint will also help keep the heat out of the cabin.

Best speed in 5th gear?

I'd say, the slowest you can go without lugging the engine or having other issues. I saw a recommendation once, saying that a car's optimum steady-state operation was at the lowest speed where you could drive in the highest gear without lugging.

This might well turn out to be 40 mph. But I'd still say, best steady state FE will be the speed where it will run in 5th without lugging.

A ScanGauge is really good for answering questions like these definitively for your car.

Well I can say about best speed for FE varies depending on the cars gearing on the road your on. I know in 5th gear on my car I can go ~28 mph without lugging the engine on a flat road but I get better FE when going ~35-40 mph. Your cars Cd has a huge effect on this. While drag isn't a huge issue at slow speeds, its still a concern. Obviously the faster your going, the more drag plays a role since drag increases with the square of speed.

Remember there are two variables when calculating your FE.. your fuel consumption and your distance traveled using that fuel. The faster your going the more miles your traveling per unit of fuel used. The total amount of fuel burned might be less be a tiny bit less at lower speeds, but if you can go further distance for just a bit more fuel it might work out to be a higher FE.

The only real way to know is to have some sort of instantaneous FE gauge (ie scangauge)


What it really boils down to is getting into the engines peak efficentcy range, which is different for engine and transmission combination and isn't always right above the lugging point.

Whatever you do, just keep playing around with it. I know when I first came here I was averaging 60mpg tanks and my last tank was 85mpg. Now that its taken a turn for cold, I'm having some difficulty but my FE is MUCH better after learning some tips and putting them to practice. Also, I know it might be hard to not compair yourself to others numbers, but everyones commute is different and short commutes do not make it easy to get super high numbers... I have no doubt that if I was driving over 20 miles for my commute each day, I'd easily be averaging in the 80's right now. Seeing how my commute is like yours (< 5 miles a day) I can definitely feel your pain.

Thanks guys for all your replies. I just ordered the SGII and hope that I can monitor it to adjust my driving habits somewhat. As I suspected, the most efficient driving would probably be the highest gear the vehicle will pull in at the desired speed. I think I do pretty well at slow, even acceleration (usually in 5th by 30-35 mph). I guess the SGII will help me see what the most efficient speed in 5th would be.

About engine temps...would a warmer thermostat have the same effect as blocking the radiator? What would be the max temperature be? Wouldn't want to overheat, and I AM still making payments on the car.:D

I'm still unsure about P&G. I understand the concept; it's just that I don't know what speed I would/should "pulse" to and at what rate (hard/gentle/medium acceleration), and what speed I should "glide" to before pulsing again.

I feel kinda funny about FAS as well. When would FAS be appropriate? "Popping the clutch" for restart....I dunno. Hard on the clutch/transmission? I don't think I'd have a problem with the steering/braking...it just seems like the gain's not worth the pain (but what do I know).

Oh...one more thing. When you fill up, what's your method of being consistent with the fill level. I saw a TV show once on mileage that suggested the only absolutely reliable method would be to fill until gas stays visible in the filler neck. Doesn't seem particularly safe (although I've been doing that for years), but I do get a significant increase in mileage/tank. Usually takes >100 mi. for the gague to budge from F as the gas in the neck is burned.

JimboK...down farther south...between J'ville and Wilmington (sort of).

Thanks again

ME

A hotter thermostat will not help like a radiator block will. Your warm up time will be the same and its still too much cooling area to let the engine stay hot... espessialy if your FASing. A radiator block reduces the amount of air flowing through the radiator to reduce its cooling effectiveness. Remeber your cars coolant system is designed to keep your car in operating temps during the most extreme of temps (ie going up a mountian in california when its 120 degrees outside.) Driving like a hypermiler means there is nowhere near the need for such a large cooling system. I've heard numbers thrown around in the 210-220 range as the maximum safe temp. I'm sure it varies with engine though. I'd have no issues with my car running it that high. Also, when FASing air is still blowing through the radiator cooling off the coolant and the engine isn't running, which means your getting out of operating temp. A radiator block helps stop this. You can also use your heater to control excess heat if your really worried about it. I know with my current 50% block I'm seeing temps ~198-200. If I turn my heater on to the lowest setting, within 30 seconds my engine coolant goes down to 180. I could run more of a block and just watch the scangauge and run the heater more if the engine starts to get a little hotter than I like. I'd personally would like to have temps around the 210 range, but I'm going to have to make a new radiator block for that.

FAS would be appropriate anytime you would be coasting down a hill, coming up to a stop light or sign, or anytime you see traffic backed up. If you want to try P&G driving you'll be FASing a LOT. Personally I havn't really got the hang of P&G yet but I'm still seeing ok numbers driving without using it. "popping" the cutch is the way to do start the motor back up, but another way of saying is bump starting. If your really worried about clutch wear just put it in the highest gear (5th or 6th) and let the clutch out, then change it over to whatever gear you want to be in. The transition is silky smooth for me when I bump start in 5th in the Insight.

FASing certainly is worth the gain! On my route from my house to the parents house, Theres a hill where I start my FAS and I can coast the rest of the way from there into my parents driveway. Its about a 3/4 mile long glide. I know my MPG numbers on my segment gauge usually jump by SEVERAL numbers. When I set my previous PR on the commute before I got my MIMA, I was sitting around 110 mpg's for the drive before I started my FAS. It jumped to 121.2 mpg's when I ended up in the driveway. Anytime you can take advantage of a hill to keep your vehicle speed up with the engine off, I'd do it. It works even better if your coming up to a stop light as your going to have to stop anyway... why waste the gas running your engine up to the stop? Turning off your engine while waiting at a stoplight also helps alot as long as the stop is > 10 seconds. Idling your engine is fuel being burned while providing you no movement.

As for Fill method, I just put whatever in and get it to a round dollar figure. Making sure you fill up the same amount really isn't that big a deal since any variences will average out after several tanks of figuring out your FE.


EDIT: as for P&G driving, I can't help you there as everytime I've tried it, I got the same numbers as I would have just driving normally or ended up with less. Obviously I havn't figured it out quite yet ;) Every car will be different in terms of how fast to accelerate and what speed to glide at, but since your getting a scangauge you can use the TPS gauge and the GPH gauge to monitor your pulse rate. Also there is a pretty good guide in here somewhere about using P&G in a HCHII that should pretty effectively describe the idea. The pulse points and speeds may not be the same for your focus but you'll get the general idea.

http://www.cleanmpg.com/forums/honda/t-pg-techniques-for-the-hch-ii-4521.html

http://www.cleanmpg.com/forums/showthread.php?t=5845

Are two threads about P&Ging in the HCH-II

After I read them I had the general idea of how and why to do it ;)

The 5 mile trips are killing you at your skill level at this point.

Just keep working it. You will find your shift points of interest. :)

Im a fas'er and load driver for the most part. Then I have a evil side that likes WOT. All you have to do is look at my tank logs. :) As much fun as sport fas'ing can be at time. Well ,,, there is more fun to be had with the engine on. I'm sick I tell you sick... LMAO

As for the tires. Keep them rotated and do what you want with the psi. I run the 17's on my Mazda 3 between 50 and 55 psi. They are wearing poorly. But not because of tire psi. I keep the tires on the wifes Accord at 44 psi. They are wearing great. She isn't a aggressive driver at all. Its up to you....

Enjoy your mpg...........

psy

I let my evil side out on Friday when I got the crx going again. Fas is not an option when driving a car that barely starts, and the battery dims when not on the throttle. I imagine my FE on that car was pretty bad, but atleast it was warmer out so the engine was not cold.

Thanks for all the great suggestions. I've inflated the tires to max sidewall pressure (44 psi), added a bottle of injector cleaner on the last fillup, trying to be more conscious of situations where coasting is possible, and even figured out a couple of places in my usual routes where FAS will be possible. Tomorrow I block off some of the radiator (where's that darn aluminum foil?).

I know those short trips are killing my mileage, but the grocery store is only 2.5 miles away, work 3 miles away (and I'm too old and fat to bike there). I'm actually trying to come up with a reason to take a longer drive to test all these newfound techniques.

Anyways...thanks again!!

ME

Reminds me about what one of my professors said about "peak" or "max" anything...

"Max MPG" = the mpg you are guaranteed to never achieve.

Hi Shifty35:
Reminds me about what one of my professors said about "peak" or "max" anything...

"Max MPG" = the mpg you are guaranteed to never achieve.___That was funny :D :D :D But we will all keep trying anyway ;)

___Good Luck

___Wayne

Reminds me about what one of my professors said about "peak" or "max" anything...

"Max MPG" = the mpg you are guaranteed to never achieve.

I've been trying to think of a roadtrip, and there's a little town near Greensboro called Climax.....um...nevermind:eek:

Ahem. Anyway, to update...the SG arrived yesterday:woot: Spent today calibrating it. To my suprise (and delight), the car's trip odometer underreports mileage, which means I've been getting better FE than I was thinking:Banane31:

Ok...three smilies in one post...SOMEONE STOP ME, PLEASE!!!!

According to the SG trip odometer and gas pump, with my testing various driving conditions today (interstate, town, country roads) I managed to get 48.12 mpg. I'm as pleased as punch. Can't wait to try and raise that figure, now that I have some idea what speeds yield the best FE for my car.

Road trip tomorrow to Oak Island (about 170 mi. round trip). Should be a great chance to see what sort of numbers I can expect in the future.

Thanks again for all the great suggestions.

ME

Oak island is a great place! I love the outer banks. Be sure to post any pictures if you take some!

Pics...will do

By the by....is there a way to get the green FE report thing to auto update when tanks are added?

Thanks

ME

Hi Menglish:

___The tank update is usually just a few minute wait. Let us know if you have not already seen the change.

___Good Luck

___Wayne

Hi Menglish:

___The tank update is usually just a few minute wait. Let us know if you have not already seen the change.

___Good Luck

___Wayne

Someone suggested to me to clean the cache. That works every time and you should then see the change right away.

BTW, there are a lot of things that will work to improve gas mileage, but it is a good idea not to try them all at once. I think that if you have your tires pumped up and you are doing slow accelerations and stops, you should add just 1-2 new tricks at a time. Try them and work to perfecting them. I think DWB (driving with buffers) is kind of a key technique, and the basis to be able to do a lot of other ones. Then I think that driving with load (DWL) and coasting in neutral are right up there, etc. FAS is based on neutral coasting, etc. etc.
The thing is is not so much which things to try first though but to really take it easy and learn new things and not get overwhelmed. There is a lot to learn.

--des