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-   -   Shifting question: First second then fifth, or use every gear? (https://ecomodder.com/forum/showthread.php/shifting-question-first-second-then-fifth-use-every-38010.html)

Spaghetti Man 11-29-2019 05:50 AM

Shifting question: First second then fifth, or use every gear?
 
I've gotten a Honda Jazz 2003 with about 251,000 km and first tank I've managed 40mpg with mainly 80-90km driving.

If I am starting in a 80km zone I will go from first gear, second gear then into fifth gear when I am around 60km per hour until 80km cruising speed.

If I am in 60km zone I go first, second then fifth gear around 50km per hour up to 60km cruising speed.

This changes slightly if there is a hill and I need a lower gear than fifth.

My sister says I should use every single gear and not skip any gears.

I think that's silly.

What do you think?

Fat Charlie 11-29-2019 06:53 AM

Skip all you want. Try neutral in bits where you don't actually need to be on the gas.

slowmover 11-30-2019 03:55 AM

I use a four ton pickup. Every gear, every time as per operators manual. And, unlike the majority of owners, the clutch is still original at nearly one quarter million miles.

It’s an attitude. If longevity matters most (true economy) the most conservative use is indicated. If FE matters most (false economy) a faster component degradation curve is accepted.

Choose well

.

iikhod 11-30-2019 06:44 AM

This obviously variates between cars but has anyone actually measured the consumption difference in skipping gears vs every gear in acceleration?

I myself accelerate with all gears. Cars generally go much smoother that way IMO.

Fat Charlie 11-30-2019 11:16 AM

Most vehicles rated below 4 tons aren't designed to haul loads well. They aren't even designed to haul groceries well. They're designed to appeal to focus groups with meaningless things like 0-60 times.

So yes, staying in the part of the band with the most power and climbing steadily through the gears will get your full load smoothly and safely to cruising speed. And because of herd mentality pushed by marketing demands, 2nd gear will take you up to or close to 60 mph: my little econobox will get to 50. Top gear should be a perfectly acceptable way to get from 50 or 60 up to whatever your desired cruising speed is unless you're loaded, on a hill or have some merging requirements. At which point, that's what all the other gears are for.

Automatics do the same thing, made even more pronounced if you engage their "eco" mode. Some manuals have even had a 1-4 skip "feature" to raise fuel economy. I haven't heard anything about it in more recent years, probably because the very few people who go out of their way to buy manuals resent an automatic system making gear decisions for them.

cRiPpLe_rOoStEr 11-30-2019 04:06 PM

Skip-shifting may be an effective fuel-saving measure for some vehicles, but I'm sure it's not an one-size-fits-all approach. Well, even though it seems newer cars have a smaller spread between one gear to the next, I didn't take the risk in the majority of the seemingly-underpowered vehicles I drove.

jakobnev 12-01-2019 07:04 AM

You have to skip-shift well, for example when performing a 2-5 shift you have to spend more time in neutral so the input side of the transmission has more time to slow down, in order to not force the syncro.

Daschicken 12-01-2019 04:30 PM

I tend to use every gear for the most part, adjusting shift RPMs accordingly.
As Jacob hinted at, to skip shift with minimal wear, let the clutch out in neutral and let the RPMs drop until they match for the gear you are going into.
60km/h sounds a little high for second gear, would that be around 4K RPM? Maybe more worthwhile to use 3rd as well.

oldtamiyaphile 12-02-2019 06:05 AM

Last time I daily drove a 1.6 petrol, my best tank was skip shifting 1-3-5.

Most 4cyl cars are so short geared that skip shifting is the way to go.

Remember some GM V8's had a shift lock out that forced you to go from 2nd to 5th to help economy. I don't have any car what will happily shift from 2nd to 5th though.

Tahoe_Hybrid 12-03-2019 07:12 AM

Quote:

Originally Posted by Fat Charlie (Post 612419)
Skip all you want. Try neutral in bits where you don't actually need to be on the gas.

Fuel Cutoff, DFCO on the down hills

Fat Charlie 12-03-2019 07:24 PM

Sorry, engine braking is still braking. EOC on the downhills, DFCO when you need a little braking.

redpoint5 12-03-2019 07:35 PM

I often skip 3rd to 6th. The acura has silly close gearing, and people tend to accelerate slowly, so if I'm limited to the acceleration of the guy ahead, then I'm skipping some gears and loading the engine a little more.

Xist 12-04-2019 11:02 AM

People also choose vehicles based on bluetooth connectivity and Apple Play.

MetroMPG 12-04-2019 01:20 PM

I routinely shift 1-3-5 in the MPGiata. It's geared super-sporty-low, even wth the oversize rear tires I put on to get the RPM down a bit.

Sometimes I am seduced into the 1-2-3-4-5 routine, simply because it truly is a fun shifter to use. So I play race-car driver once in a while.

Then I reach 50 km/h / 30 mph and calm down. :D


I haven't driven the Mirage enough to figure out if skip-shifting will be par for the course, though I have done it more than a couple of times.

mpg_numbers_guy 12-04-2019 02:18 PM

If I'm accelerating above 30 mph I go through every gear. Otherwise for 20-25 mph I do 1-2-4, for 25-30 I do 1-2-3-5. Obviously this depends on hills where I usually have to shift closer to 3-3.5k RPM versus 1.5-2.5k normally.

Fat Charlie 12-04-2019 11:11 PM

Getting to highway speed, unless there's a real sense of urgency it's 1-2-5.

iikhod 12-05-2019 12:43 AM

Quote:

Originally Posted by MetroMPG (Post 612779)
Sometimes I am seduced into the 1-2-3-4-5 routine, simply because it truly is a fun shifter to use. So I play race-car driver once in a while.

Then I reach 50 km/h / 30 mph and calm down. :D


"This is not le mans!" :D

elhigh 12-05-2019 11:53 AM

First > Third > Fifth, when unloaded and on level ground.

It's really a question of the driver and the mission, so it's up to you to be aware of what you're doing to know when to skip, and if you should.

My truck with nothing in the bed, First is way low. Second would work but demands just a bit too much clutch slippage for my preference. Third, coming out of First, is low enough engage without lugging but still tall enough to comfortably pull all the way to 45mph, by which time Fifth is in the torque zone. Know your engine, transmission and loading and the shifts will suggest themselves.

My original clutch went about 200,000 miles, and I've been driving this truck this way the whole time. It was my second kid learning stick that killed it. And that was worth the sacrifice.

Ecky 12-05-2019 02:05 PM

Really depends for me. I have tall gearing and 6 speeds in the Insight, and a moderate-to-short 5 speed in the Fit.

My wife gets closer to 50mpg in the Fit during summer, and is averaging closer to 40 with weather hovering just below freezing, and ice/slush on the roads. She always uses all 5 gears but tends to slam through them quickly at low speeds, typically 5-12-18-25ish and accelerates with high load in 5th from 25. I'm not sure if she ever revs it above 1500RPM when accelerating before getting to 5th gear.

In my Insight I tend to vary my shift pattern. More often I use all of the gears. 6th isn't really appropriate until ~35mph where it's at ~1150rpm. Gears 1-2-3 are a hoot with the ~250HP engine so when I'm driving more spiritedly I'll hang onto 2 or 3 a little longer and then go straight to 5 or 6. 2nd is good for ~80mph and 3rd for 110 so it's not like I'm being forced to shift.

slowmover 12-08-2019 07:13 PM

Quote:

Originally Posted by elhigh (Post 612835)
First > Third > Fifth, when unloaded and on level ground.

It's really a question of the driver and the mission, so it's up to you to be aware of what you're doing to know when to skip, and if you should.

My truck with nothing in the bed, First is way low. Second would work but demands just a bit too much clutch slippage for my preference. Third, coming out of First, is low enough engage without lugging but still tall enough to comfortably pull all the way to 45mph, by which time Fifth is in the torque zone. Know your engine, transmission and loading and the shifts will suggest themselves.

My original clutch went about 200,000 miles, and I've been driving this truck this way the whole time. It was my second kid learning stick that killed it. And that was worth the sacrifice.


High reasonability. But the door open to, “man & mission“, is an escape clause negating the rest. (I get what’s being said). Below is general, not specific to the man or his post:

First on mine is a granny when solo (1200-lbs above ship weight). All that’s being done is getting momentum started. And, at that, it’s great. The First to Second shift is immediate. Just a few feet (is how it feels).

“Normal” for a vehicle is when loaded close to spec.

“Abnormal” (driver only) is NOT how to establish driving habits.

If I drive as if my trailer is always in tow (not an 8,000-lb truck, but an 18,000-lb combined rig where the tractor MUST pivot far outward on turns), anything solo makes problem-solving easier. The only corner I cut is a decrease from an almost 90-degrees. After all, one can never steer by following the front wheels. It’s always the pivot off the Drive Axle.

Driving is about timing. The order thence is Steering & Braking. Throttle Use is a far distant third.

The throttle exists to get you to the gear best suited. It doesn’t have much other use.

Best suited (means) fewest possible changes from lane-center while steady-state.

If that means a higher rpm than thought ideal so as to emphasize engine braking on a suburban feeder road, then such it is.

Weather shouldn’t much change the equation. Nor should load (see previous). Only traffic volume is the wild card. As the requirement for separation distance never changes (time, and speed, to impact).

So I can’t see the point of gear skip. Faster component wear PLUS habit incommensurate with loaded vehicle versus traffic volume problem.

What I’m speaking of isn’t “virtual”.

The belief that skill & awareness will overcome consequences is what’s not supported statistically, is the virtual construct.

The premise, “there are no accidents”, covers this.

(Brakes won’t and don’t solve operator-error problems)

.

slowmover 12-08-2019 07:27 PM

With the trailer in tow — on rural South Central U.S. Interstate — I have to know:

1). At what road speed I can downshift from OD to Direct to maximize braking effect (as a diesel has no closed throttle engine braking); so as to,

2). Undertake any high speed emergency maneuvers contemplated.

As I already know I can undertake throttle-on violent shoulder to median and back wheel cranks at 55-mph, I can’t really be traveling faster than an rpm which allows a downshift so fast it happened yesterday.

Have to bring the engine back in at under 2900-rpm (redline).

As that would be a speed I might (unlikely) undertake to pass a drunk, I don’t sweat it.

But I do bring it up for your own vehicle and habits. No wheelspin, full steering control.

Take the test. A normal load of 75% or better. Wet road.

A severe downslope highway exit with a turn near the end under icy conditions.

A kid can learn to upshift easily. What separates him from men is the dangerous conditions downshifts where brakes alone are a VERY bad idea.

Some of the tankers I drove were 18 shifts on the way up, and another 18 on the way down. Bright, sunny days with no traffic or hills. (Eleven shifts and barely above 20-mph and a big intersection).

Proficiency is up and down. Thus, “every gear every time”, is a basic.

.

Tahoe_Hybrid 12-09-2019 10:20 PM

Quote:

Originally Posted by Fat Charlie (Post 612738)
Sorry, engine braking is still braking. EOC on the downhills, DFCO when you need a little braking.

haha the vehicle is so heavy it speeds up since the engine braking is only enabled on M4 mode it runs

DFCO on Regeneration braking instead


Also mine is differ then the normal hybrid models i can run EV mode to 29MPH while others it turns on at 25mph :eek:


I can also trick the REG unit to regenerate while i'm speeding up on the down hill at 88 mph it can generate 60KW sorry not 1.21 jiggawatt

kurzer 12-20-2019 07:24 AM

to get from 2nd to 5th, u have to use the 2nd gear mutch longer, wasting fuel for reving the engine. i use every single gear asap.
skiping gears is a good help for drivers, who are afraid of lower revs. so they can learn about the performance.
and maybe its good for lazy drivers.

but, in some cars i would skip 1st gear, usually.

PaleMelanesian 12-20-2019 11:42 AM

Sometimes I use 12345. If it's downhill I start in 2. Sometimes I'll go 1-2-4-6, oh wait I don't have a 6th Aaaargh I guess 5th will do.

Seriously the gears in this car are so short it's ridiculous. 5th gear hits 2000 rpm at 40 mph.

T Durden 12-20-2019 05:38 PM

Wouldn't it be best to shift so that you are using your engine's "Island of Efficiency"?

I found my Insight's island to be between 2000 - 3000rpm, so I'll shift at 3000 for first and second gear, and the revs drop to about 2000. By the time third gear gets to 3000, I'm moving fast enough to shift to fifth. So 1,2,3,5 for me.

*I'm not using my hybrid battery though.

Ecky 12-20-2019 07:19 PM

Quote:

Originally Posted by T Durden (Post 613658)
Wouldn't it be best to shift so that you are using your engine's "Island of Efficiency"?

I found my Insight's island to be between 2000 - 3000rpm, so I'll shift at 3000 for first and second gear, and the revs drop to about 2000. By the time third gear gets to 3000, I'm moving fast enough to shift to fifth. So 1,2,3,5 for me.

*I'm not using my hybrid battery though.

I always had my best numbers shifting as low as possible.

Fat Charlie 12-21-2019 07:42 AM

Using the island of efficiency and every gear would be right for me if I were under load. Like pulling a yard of topsoil. But even my puny little 1.5l is overpowered for the task of driving me and maybe some groceries around.

Getting up to highway speed involves winding it up through second, then using either third or fourth to get to cruising speed. One end of my drive has an onramp where traffic is unpredictable, I may need to be going anywhere from 60-80 to merge easily. The other end is uphill from a light, where railroad tracks dictate a shift. I'd grab fifth there, but it's an uphill and I generally have cars behind me. The 1.5l isn't so overpowered that accelerating uphill in fifth from 45-50 is polite to others.

Plasmajab 12-24-2019 05:05 PM

Ill toss in a spin on it.

For my ranger:

1st 3.91
2nd 2.24
3rd 1.49
4th 1.0
5th 0.8

1st - 2nd =1.67
2nd - 3rd = 0.75
3rd -4th = 0.49
4th - 5th = 0.20

So lets do a 1 - 3 -5 shift.

1-3 = 2.42
3-5 = 0.69 (Nice)

So shifting from 1st to 3rd is a pretty huge drop in my ranger. You'd have to rev it pretty high to get to 3rd happily, but 3rd to 5th is not as huge of a gap.

In my ranger, 1st gear pretty much is like a "Bull low".. Enough to get the truck rolling but little else.

All the numbers are greek to me. Ill have to do some real world testing. Personally on my western star. YMMV. Basically shifting when the engine is in its peak torque curve with as little rpm as required.

So without "splits"

3rd 1000rpm
4th 1100rpm
5th 1200rpm
6th 1300rpm
7th 1400rpm
8th 1500rpm

For my western star, 1000-1700 is where it makes its peak torque. Basically keeping the engine running in the lowest part of the torque band. But I wonder how this would effect a regular car or truck. Of course the rpms would be higher.. But I think Im going to test this out. Thankfully I just so happened to fill my tank.

slowmover 12-25-2019 05:10 PM

Quote:

Originally Posted by MetroMPG (Post 612779)
I routinely shift 1-3-5 in the MPGiata. It's geared super-sporty-low, even wth the oversize rear tires I put on to get the RPM down a bit.

Sometimes I am seduced into the 1-2-3-4-5 routine, simply because it truly is a fun shifter to use. So I play race-car driver once in a while.

Then I reach 50 km/h / 30 mph and calm down. :D


I haven't driven the Mirage enough to figure out if skip-shifting will be par for the course, though I have done it more than a couple of times.


I think you (used to, before millions of cretins invaded) be about pack center in this.


I was running tanker with a quite unstable load a few years back. 18-gears up and 18-gears down. Every time. Anything to keep from waking up that monster. ALWAYS at or above 40-tons.

On a major metro street (six lanes) meeting another thus a quite large intersection, I’d have 11-12 shifts completed before clearing that intersection at 22-mph. With 6-7 to go to hit 50-mph.

Y’all crack me up with the impatience. Shifting is just a rhythm. Didn’t any of you learn to sing or play music (means nothing Electric needed)? Did you only learn to perform three bars out of a number?

Correlate the other actions of your life. The ancient, “in it, but not of it”, admonition. For which your car will thank you.



.

wdb 12-25-2019 05:15 PM

Accelerate briskly and skip shifts.

And put an undertray on your Jazz -- you will be flabbergasted at how it makes the front of the car so much more well behaved. Not to mention trimming a few tenths off the MPGs.

And put the lightest wheel/tire combination you can find on it. They get so much more nimble and tossable with light feet!

A properly outfitted Jazz makes hypermiling fun.

slowmover 12-25-2019 05:29 PM

Quote:

Originally Posted by Plasmajab (Post 613849)
Ill toss in a spin on it.

For my ranger:

1st 3.91
2nd 2.24
3rd 1.49
4th 1.0
5th 0.8

1st - 2nd =1.67
2nd - 3rd = 0.75
3rd -4th = 0.49
4th - 5th = 0.20

So lets do a 1 - 3 -5 shift.

1-3 = 2.42
3-5 = 0.69 (Nice)

So shifting from 1st to 3rd is a pretty huge drop in my ranger. You'd have to rev it pretty high to get to 3rd happily, but 3rd to 5th is not as huge of a gap.

In my ranger, 1st gear pretty much is like a "Bull low".. Enough to get the truck rolling but little else.

All the numbers are greek to me. Ill have to do some real world testing. Personally on my western star. YMMV. Basically shifting when the engine is in its peak torque curve with as little rpm as required.

So without "splits"

3rd 1000rpm
4th 1100rpm
5th 1200rpm
6th 1300rpm
7th 1400rpm
8th 1500rpm

For my western star, 1000-1700 is where it makes its peak torque. Basically keeping the engine running in the lowest part of the torque band. But I wonder how this would effect a regular car or truck. Of course the rpms would be higher.. But I think Im going to test this out. Thankfully I just so happened to fill my tank.

I doubt you drive much differently empty or loaded. It’s a bad habit to change up for the temporary empty condition. No one cares about your non-revenue miles. Just the loaded ones. Same rules apply (vehicle design).

Thus (for anyone, but around here they’re not interested in economy), you’ll want to load that personal vehicle to 80% of sticker or higher. 13-weeks minimum (calendar quarter; valid habits change with zero deviation) of record-keeping.

Be a good idea to load it per above and take it out for a hard highway run. Heavier, if you can manage it (trailer for higher aero resistance). An Italian tune-up preceding a habits change is necessary.

It’s “fun” to do the Kevin Rutherford thing, so in your personal vehicle you want a feedback gauge to use. An engine hour meter, as metro driving is about

Never idling & Never Stopping

as, it’s your Average MPH that’s at stake.
Higher = Better.


When to Shift
How to Shift

will fall into the decision previously-made to emphasize engine/trans braking for that road stretch. Street type plus traffic & weather. The, “Do Not Exceed”, reference you establish. IOW, a 50-mph road on which you never exceed 45 as that’s a shift point that takes you from Direct into OD.

Then — inside of that — is finagling with some rpm changes.

Empty, anything goes. But it has no meaning. It’s Y x 0. Nice guys here, next to none are serious. The loaded tests are the baseline against an empty by which to know the percentage gap to close. One has to work the drivetrain and brakes plus steering to affect a loaded vehicles momentum in a positive manner. Penalties are immediate. (As they should be). “Empty” pickup only exists on paper, is another way to say it.

TARE, is useful, sure. So is sub-60/mph on cruise. Those numbers represent the possibilities. They just aren’t real.

IOW, the difference between Town & Country can disappear given reasonable use. I took mine to under 10%. Same 1200-lb load. (Truck in sig. Stock. Minimum-allowed tire pressure.) 24-MPG Highway. 22-MPG city.

A plan is required. UPS “No Left Turn” Routing. An errands loop where the farthest point was reached by freeway FIRST. Work back to house. Etc. Accomplish the necessary, but with lowest fuel burn and never compromising safety.

The Key: Once you know the gear choice that promotes throttle-off slowing so that you never have to come to a stop, the rest is an easily-managed daily drama. It’s acquaintance with the roads (as you already know) that make those predictions easier.

Just pretend you’re humping around town for YRC in a day-cab & pup. Just none of that heart-stopping blind-side backing, ha!

.

Tahoe_Hybrid 01-03-2020 04:39 AM

Quote:

Originally Posted by slowmover (Post 613889)
I doubt you drive much differently empty or loaded. It’s a bad habit to change up for the temporary empty condition. No one cares about your non-revenue miles. Just the loaded ones. Same rules apply (vehicle design).

Thus (for anyone, but around here they’re not interested in economy), you’ll want to load that personal vehicle to 80% of sticker or higher. 13-weeks minimum (calendar quarter; valid habits change with zero deviation) of record-keeping.

Be a good idea to load it per above and take it out for a hard highway run. Heavier, if you can manage it (trailer for higher aero resistance). An Italian tune-up preceding a habits change is necessary.

It’s “fun” to do the Kevin Rutherford thing, so in your personal vehicle you want a feedback gauge to use. An engine hour meter, as metro driving is about

Never idling & Never Stopping

as, it’s your Average MPH that’s at stake.
Higher = Better.


When to Shift
How to Shift

will fall into the decision previously-made to emphasize engine/trans braking for that road stretch. Street type plus traffic & weather. The, “Do Not Exceed”, reference you establish. IOW, a 50-mph road on which you never exceed 45 as that’s a shift point that takes you from Direct into OD.

Then — inside of that — is finagling with some rpm changes.

Empty, anything goes. But it has no meaning. It’s Y x 0. Nice guys here, next to none are serious. The loaded tests are the baseline against an empty by which to know the percentage gap to close. One has to work the drivetrain and brakes plus steering to affect a loaded vehicles momentum in a positive manner. Penalties are immediate. (As they should be). “Empty” pickup only exists on paper, is another way to say it.

TARE, is useful, sure. So is sub-60/mph on cruise. Those numbers represent the possibilities. They just aren’t real.

IOW, the difference between Town & Country can disappear given reasonable use. I took mine to under 10%. Same 1200-lb load. (Truck in sig. Stock. Minimum-allowed tire pressure.) 24-MPG Highway. 22-MPG city.

A plan is required. UPS “No Left Turn” Routing. An errands loop where the farthest point was reached by freeway FIRST. Work back to house. Etc. Accomplish the necessary, but with lowest fuel burn and never compromising safety.

The Key: Once you know the gear choice that promotes throttle-off slowing so that you never have to come to a stop, the rest is an easily-managed daily drama. It’s acquaintance with the roads (as you already know) that make those predictions easier.

Just pretend you’re humping around town for YRC in a day-cab & pup. Just none of that heart-stopping blind-side backing, ha!

.

the 60MPH rule is point less depending on the vehicle a good example is going 75mph Actually uses less fuel then going 55 or 60mph


at 75mph it's 14-15mpg on the DIC reported 4th gear v8 mode

as going 60mph will drop it to 3rd gear..the DIC says 9-11mpg


ON a hilly area



if you say go slower 40-45mph on flat land will yield 31MPG in EVT mode

the Op will have to find the Sweet spot on his vehicle

Silent Blood 07-15-2020 06:45 AM

Quote:

First second then fifth or use every gear?
It depends on the road nature and the gradation of the transmission. When I drove downhill, I often use the 2. th gear, then shifting directly into the 5. th (ans highest) gear.

Charlie Cheap 10-29-2020 04:56 PM

When I built my last 1940 Ford coupe (I have owned 5) I built the 289 out of a 67 Cougar with a 3-speed standard. Everyone asked why a 3-speed rather than a 4-speed. I explained it was better to get into high gear as soon as possible, without lugging the motor, for best economy. With the big car flywheel that was about 10 pounds heavier than the Mustang/Cougar, with 2-barrel, 2.79 gears, 29" tall rear tires, and the engine built for torque at highway speed RPM, it worked great on the interstate. To get 24/25 MPG with 250 HP in a 1940 Ford coupe with tilt steering, multi-speaker stereo, Air Conditioning, cruise control, custom upholstered bucket seats, and Black Lacquer paint that looked wet, was another fun car I drove for 12 years.

Ecky 10-29-2020 06:39 PM

Quote:

Originally Posted by Charlie Cheap (Post 635004)
When I built my last 1940 Ford coupe (I have owned 5) I built the 289 out of a 67 Cougar with a 3-speed standard. Everyone asked why a 3-speed rather than a 4-speed. I explained it was better to get into high gear as soon as possible, without lugging the motor, for best economy. With the big car flywheel that was about 10 pounds heavier than the Mustang/Cougar, with 2-barrel, 2.79 gears, 29" tall rear tires, and the engine built for torque at highway speed RPM, it worked great on the interstate. To get 24/25 MPG with 250 HP in a 1940 Ford coupe with tilt steering, multi-speaker stereo, Air Conditioning, cruise control, custom upholstered bucket seats, and Black Lacquer paint that looked wet, was another fun car I drove for 12 years.

I'll admit I'm skeptical of less gears = better, as evidenced by manufacturers adding more and more gears to chase economy, but those are more than decent numbers for a car of that era.

~

Today I found myself using 2nd to 6th a couple of times. 2nd gear will do approximately 78mph but the engine has gobs of torque, so I took 2nd from a stop out to around 35 and then straight into 6th. I'm certain this wasn't best for economy, but it was certainly lazy, and I got around 47mpg on my return commute, all city driving in the rain with the outside temperature in the 30's.

cRiPpLe_rOoStEr 10-29-2020 08:02 PM

Quote:

Originally Posted by Ecky (Post 635010)
I'll admit I'm skeptical of less gears = better, as evidenced by manufacturers adding more and more gears to chase economy

Sure the one-size-fits-all approach doesn't apply, but sometimes a higher amount of gears is not so effective regarding fuel savings and overall performance improvements. Some newer manuals have an excessively narrow gear spread, and a shorter differential ratio is needed in order to give it a minimally reasonable responsiveness from a standstill.

Michaelflat1 10-31-2020 11:04 AM

I too have a Honda Jazz... 2007.
5 speed manual, i do not believe in skipping gears usually.

For constant acceleration, change up gears as early as you can, holding 2nd gear to 50kmh for example means you are holding that gear too long... Unless you are rocketing up to 50kmh at optimum load.

On my jazz, city driving i upshift really early and keep the engine loaded. With careful use of throttle (not too much, not too little) i have these shift points:

1>2nd ~7-8mph (1800>1100rpm)
2nd>3rd ~15mph (1700>1200)
3rd>4th ~20mph (1400>1100rpm) (going off memory all these rpm figures so maybe wrong)
4th>5th ~25mph

These are ultra low RPMs for accelerating... but using torque pro i'm not using too much throttle (which would cause engine knock) and acceleration is not awful.
I've achieved indicated 70+mpg (UK) just around town at 3am after dropping friends home. The jazz seems to really like low RPMs (mine's a 1.3 idsi)

Effective use of DFCO also is good, you need to be above 1500rpm to activate DFCO in jazz, so i find myself dropping a gear / dropping 2 gears when i need to slow down. (rev matched too... dragging the engine rpm up with the clutch kills momentum)

MetroMPG 10-31-2020 12:19 PM

Welcome to the forum, Michaelflat1!

What size engine is in your Jazz?



How did you determine the fuel cut-off point (RPM) - does the car's gauge show instant fuel consumption?

Stubby79 10-31-2020 12:24 PM

First, second, fifth.
...is how I drove my small displacement cars. Ie Miata. You could get up to any legal speed in 2nd, so I would use it to get to speed ASAP and then straight to 5th for economy, and because I didn't need to accelerate any more.

Couldn't skip more than one gear in the 'metro, mind you.

First, third, sixth.
...is how I drive my Z. The close gear ratios and big engine make using all the gears pointless, unless you're trying to have fun. Feels like you're driving a normal 4 cylinder car, if you shift like that at lower RPMs.

The idea, from an economy stand point, is to keep the engine under heavy load as much as possible.

There engine/trans doesn't care what gear you put it in, unless you bog down the engine, or end up over-revving it while down-shifting. Drive how you want.

cRiPpLe_rOoStEr 11-01-2020 01:27 AM

Quote:

Originally Posted by Stubby79 (Post 635217)
The close gear ratios and big engine make using all the gears pointless, unless you're trying to have fun.

This might explain why I hardly had any chance to skip-shift, as most of the cars I drove had small engines, even though the gear spread was quite too short for my taste on some.


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