The power of hypermiling- 18 kml VTi prosmatic 2003

[ZainMahdi]

• There were two adult passengers (parents) + driver (me) in the car. A/C was not used.

• Some technical terms are used here (NICE-ON, DWB, DWL). An explanation may be found here.

• Early shifting: manipulating the accelerator pedal to shift gears as early as possible. I lifted my foot from the pedal at 10 km/h, 32 km/h, and 52 km/h. These were the minimum shift points for 2nd, 3rd, and 4th gear respectively.

• 'Lock up' refers to torque converter lock up. This car needs at least 70 km/h to go into full lockup; at lower speeds, it went into semi lock up in 3rd and 4th.

__This was my first proper fuel economy test. I have been hypermiling before without measuring my fuel consumption.

__The route started from GIKI main gate, Topi, KPK. The petrol tank was absolutely full; the car had made it to GIKI on a tank of CNG.

__The first 28 km consisted of many small towns and rural roads. Here, I used early shifting, NICE-ON, and DWB. The torque converter occasionally went into semi-lock up in 3rd and 4th gear.

__On the motorway, I used early shifting only once to get up to speed. Thereafter, I stayed in 4th gear right up to Kashmir highway.

__My techniques on the motorway were DWL, DWB, NICE-ON, and maintaining full lock up as much as possible.

__I aimed to stay around 100 km/h. In reality, my speed fluctuated between 80-110 km/h due to DWL. 80 was my lower limit, so that I could stay well into the lock up range.

__The "Hakla Climb" is a very steep ~4 km uphill just before the Islamabad exit. I tackled this by accelerating to 130 km/h beforehand, and then DWLing all the way up. By the peak of the climb, the speed had fallen to 70 km/h.

__I entered the exit at ~70 km/h, shifted to neutral, and completed the turn without using the brakes. Upon completing the turn, the speed had fallen to 60 km/h.

__From the exit all the way to the Kashmir Highway PSO pump, I used DWB, early shifting, DWL, and NICE-ON.

__The car was filled at the PSO pump before; it was filled here again to ensure accuracy. The whole trip was 89.9 km according to the odo; the fuel consumed was 4.95 liters (less than 350 Rs). The total fuel consupmtion was 18.2 kml.

__I will be happy to answer all questions, comments, and queries

[ZainMahdi]

TL;DR version:

__achieved 18 kml on my 2003 Civic VTi prosmatic, 35:65 local/motorway driving.

__used the most basic hypermiling techniques: DWL and DWB. Also used NICE-ON, which is a slightly more advanced technique.

__the myth of 10-14 max from an automatic Civic has been broken.

[mansoor_qadir]

I too got 19kmpl out of a 5AFE once but then dropped the idea as they say ''excess of everything is bad''.Whats the use of it being a hyper-miler of this level.
I mean its good but try to enjoy your drive a little or get a Prius.

[ZainMahdi]

Some limitations which prevented me from crossing 20 kml:

-20w-50 oil

-around 35 psi on the tires (I would have preferred 45-50 psi)

-headlights are not fully sealed; sunroof seal is also broken; the bonnet is bent very slightly, letting some air leak inside; the undertray is hanging from the car

-CNG kit still installed

-nervous parents as passengers, who didn't let me use FAS ( a really advanced hypermiling technique)

-no fuel economy instrumentation. In hypermiling speak, I was driving blind

-I stayed around 90-100 to avoid going too slow. 80 was my preferred lower limit (dropping to 70 at Hakla). My maximum speed was 130 at one point. I had misjudged the distance to the Hakla slope, and accelerated to 130 prematurely. When I saw the slope was still far away, I dropped to neutral, let it drop to 100, and accelerated to 130 again right before the slope.

[Xulfiqar]

trading transmission cost for mileage?

[ZainMahdi]

Surprisingly, the transmssion behaved really well when shifting from N to D. During my first N-D transition at 90, I expected the RPM to shoot up to 3.5-4k. It only went to around 2.6k, before quickly shifting to 4th and locking up. There was no unexpected jerk; it just felt like a downshifting from 4th to 3rd at say, 100 km/h. Not butter smooth, but not exactly transmission destroying-ly explosive.

[AsFand26]

I have no idea how you forced it to shift into 2nd at 10km/h. My 9th gen prosmatec stays in first at that speed no matter what.
plus, as @xulfiqar said, that shifting into N and D while moving damages the trans even if there is no hard jerk.

[usman_arooq2]

i'll try these in my khyber, specially the FAS one as there isn't much to loose even if i don't start again(no steering lock, no power steering and braking becomes mehran like instead) i often pop it outta gear without clutch if the tranny allows me to(usually with little to no accelerator input n absolutely no brake input) while approaching stop lights.

[Xulfiqar]

Surprisingly, the transmssion behaved really well when shifting from N to D. During my first N-D transition at 90, I expected the RPM to shoot up to 3.5-4k. It only went to around 2.6k, before quickly shifting to 4th and locking up. There was no unexpected jerk; it just felt like a downshifting from 4th to 3rd at say, 100 km/h. Not butter smooth, but not exactly transmission destroying-ly explosive.

the problem with almost any aatometick (except a few ancient full hydraulic shift) is that they need to stack the shifts to achieve a certain ratio - when the manual valve gate closes (shift out of D into N) all pressure to the required packs is released, this causes loss of drive and heating up as the clutches now have to spin down and depressurize without proper regulation.

Re applying drive whilst moving then forces all the ratios to apply and deapply to get to the required ratio again, this causes the clutches to overheat (trans wear happens at shifting point as the clutches have not stalled to bite 100%) - think of it as a lathe mill, once your stock is loaded into the chuck and you then move the clutch lever towards you engage the belt which at first slips (the belt wears the most as its slipping and you are trying to smoothly engage the drive - once the belt has bitten into the friction point belt wear is reduced by 95%) - a simple example only here.

[ZainMahdi]

These cars have adaptive tranmissions. When you drive usually drive them hard, the ecu knows that the driver is aggressive, and it will adjust the car's shift points accordingly. For the first few kilometers, even I was having trouble shifting that low, but the car adjusted itself eventually.

As for transmission damage, cleanmpg and ecomodders members use it frequently. As fas as I can tell, no member has suffered tranmission damage from coasting in neutral (automatic). Some cars, like Honda, and GM's new six speed models, can even be shut off in neutral without transmission lubrication issues. Near any automatic car can be coasted in neutral with the engine on, without damage. It is certainly less damaging than driving aggressively, redlining all the time, and frequently forcing the car to downshift a couple of cogs.

[ZainMahdi]

Another interesting fact about this car's fuel consumption:

My dad achieved 211 km from 8 kg of cng 3 years ago (purely GT road). I had told him about torque converter lock up and vtec-e (the economy cam profile mode). He decided to use it, and his fuel economy shot up.

He didn't use any fancy stuff like NICE-ON, FAS, DWL, or DWB. In fact, even I didn't know about these techniques back then, or hypermiling for that matter.

[Xulfiqar]

These cars have adaptive tranmissions. When you drive usually drive them hard, the ecu knows that the driver is aggressive, and it will adjust the car's shift points accordingly. For the first few kilometers, even I was having trouble shifting that low, but the car adjusted itself eventually.

As for transmission damage, cleanmpg and ecomodders members use it frequently. As fas as I can tell, no member has suffered tranmission damage from coasting in neutral (automatic). Some cars, like Honda, and GM's new six speed models, can even be shut off in neutral without transmission lubrication issues. Near any automatic car can be coasted in neutral with the engine on, without damage. It is certainly less damaging than driving aggressively, redlining all the time, and frequently forcing the car to downshift a couple of cogs.

GM six speed do not stack shifts, they have individual shift elements (hard items) to provide the ratio. Ecomodders do not rebuild transmissions or even work on their own cars, I actually rebuild automatic transmissions as a side income and I have repaired a lot of units where the owners shifted into N coasting down a hill - I usually repair Mercedes Benz NAG1 units as I find them fascinating. Nearly all of the stupid dodge charger and magnum owners who reported this had money for wheels n stickers but not for fuel, (that is beside the point here)

the point is that they damaged the unit, The expected life of a NAG1 is about 320,000 kms in service - including taxi service after which a friction parts rebuild is required to make it perform like new again. The above mentioned trans crapped out at 150,000 kms - by owners trying to outsmart the TCU.

IMO - if you shift to N whilst moving then coast to a stop and then shift to D again. But engaging D at speed will cause issues. Heavy or catastrophic wear will happen if you switch off the engine - which stops the transmission pump too. (cars towed with driving wheels on the ground - you can even google it)

the adaptive bit has no role here, the adaptation is only to ensure the transmission can stay in service longer - it records the driving input of about 50 acceleration and deceleration cycles and also a period of 20 start/stop cycles to determine what to record. This adaptation thing wont help in your shift to N while moving - as its invoking requirements are not met. meaning the transmission is actually a bit confused when D is applied again - it then would hard smack the ratios - in some cases the pressure regulator force motor (pressure regulator solenoid) can get a bit loopy from this act.

[ZainMahdi]

GM six speed do not stack shifts, they have individual shift elements (hard items) to provide the ratio. Ecomodders do not rebuild transmissions or even work on their own cars, I actually rebuild automatic transmissions as a side income and I have repaired a lot of units where the owners shifted into N coasting down a hill - I usually repair Mercedes Benz NAG1 units as I find them fascinating. Nearly all of the stupid dodge charger and magnum owners who reported this had money for wheels n stickers but not for fuel, (that is beside the point here)

the point is that they damaged the unit, The expected life of a NAG1 is about 320,000 kms in service - including taxi service after which a friction parts rebuild is required to make it perform like new again. The above mentioned trans crapped out at 150,000 kms - by owners trying to outsmart the TCU.

IMO - if you shift to N whilst moving then coast to a stop and then shift to D again. But engaging D at speed will cause issues. Heavy or catastrophic wear will happen if you switch off the engine - which stops the transmission pump too. (cars towed with driving wheels on the ground - you can even google it)

the adaptive bit has no role here, the adaptation is only to ensure the transmission can stay in service longer - it records the driving input of about 50 acceleration and deceleration cycles and also a period of 20 start/stop cycles to determine what to record. This adaptation thing wont help in your shift to N while moving - as its invoking requirements are not met. meaning the transmission is actually a bit confused when D is applied again - it then would hard smack the ratios - in some cases the pressure regulator force motor (pressure regulator solenoid) can get a bit loopy from this act.

Interestingly, I have only seen neutral coasting adviced against in two car manuals: Subaru Impreza, and all MB models. Chryslers are also known to cause problems shifting from N to D; I have read the gears and RPM bounce all over the place; the ECU expects a N-D transmission only during a complete stop. The speed greater than a dead stop confuses it.

Other than these cars though, I have yet to read about any problems with NICE-ON.

The bit about the adaptive transmission: that was in response to AsFand, who asked how I could achieve a 1-2 shift at 10 km/h.

[Xulfiqar]

Interestingly, I have only seen neutral coasting adviced against in two car manuals: Subaru Impreza, and all MB models. Chryslers are also known to cause problems shifting from N to D; I have read the gears and RPM bounce all over the place; the ECU expects a N-D transmission only during a complete stop. The speed greater than a dead stop confuses it.

Other than these cars though, I have yet to read about any problems with NICE-ON.

The bit about the adaptive transmission: that was in response to AsFand, who asked how I could achieve a 1-2 shift at 10 km/h.

chrysler use the Mercedes Benz NAG1 in all their older chargers/300s/magnums/challengers and also in jeep cherokees - They have now bought 8 spd RWD torqueflite transmissions and are using them in select models - the FWD 8 and 9 speeders are from ZF - do a moving D-N shift on any of the above and prepare to open your wallet.

[ZainMahdi]

chrysler use the Mercedes Benz NAG1 in all their older chargers/300s/magnums/challengers and also in jeep cherokees - They have now bought 8 spd RWD torqueflite transmissions and are using them in select models - the FWD 8 and 9 speeders are from ZF - do a moving D-N shift on any of the above and prepare to open your wallet.

One solution for that - no MBs or Chryslers for hypermilers :).
Actually, NICE-ON was only part of my techniques. The techniques that helped my fuel consumption best were slow acceleration, DWL, and DWB. Even MBs and Chryslers allow their use.

[ZainMahdi]

i'll try these in my khyber, specially the FAS one as there isn't much to loose even if i don't start again(no steering lock, no power steering and braking becomes mehran like instead) i often pop it outta gear without clutch if the tranny allows me to(usually with little to no accelerator input n absolutely no brake input) while approaching stop lights.

FAS is a very helpful technique. It is also very advanced, and you might want to practice on an empty road first to see how your car reacts without power. On my Cultus, the brakes last about 3 applications before the vacuum assist runs out.

Be very careful not to switch the ignition all the way to off; the consequences can be fatal. You don't want the steering wheel to lock out.

If you want to regularly use FAS, you might also want to learn how to bump-start. This will save the starter from wear and tear; the clutch is more robust than the starter.

[usman_arooq2]

FAS is a very helpful technique. It is also very advanced, and you might want to practice on an empty road first to see how your car reacts without power. On my Cultus, the brakes last about 3 applications before the vacuum assist runs out.

Be very careful not to switch the ignition all the way to off; the consequences can be fatal. You don't want the steering wheel to lock out.

If you want to regularly use FAS, you might also want to learn how to bump-start. This will save the starter from wear and tear; the clutch is more robust than the starter.

PS khyber never came with steering lock, I know how to bump start but servicing starter motor is cheaper than clutch and after driving mehrans anyone can manage without power brakes while vacuum pressure lasts 2-3 pedals.

[chdemon]

hypermiling..... getting 1-2 km more at the cost of time and so many other factors. i hate it.

[ZainMahdi]

hypermiling..... getting 1-2 km more at the cost of time and so many other factors. i hate it.

• So this car normally gets 16-17 kml in mixed driving? That's what you are basically saying.
• As for time, it cost me about 10 min extra for the whole trip. I was actually trying to keep my speed a bit high, to maintain 4th gear and torque-converter lockup.