Team-BHP - Max kmpl , and how to achieve it

agree: to some of the earlier posts. Its always a great feeling to hear your engine sing. And i guess everyone competent enough to drive a car would know that its practically impossible to shift your gears at 14.7km/hr ot at 45.8km/hr because you want to see how much F.E you can extract!!

But i just do not choose to be complacent with that feeling of practicality.:D

No offenses but i believe there is a lot more to learn out there though that deos not lead to sitting with tons of charts and ratios beside our driving seat.

Quote:

Originally Posted by gemithomas (Post 606981)

agree: to some of the earlier posts. Its always a great feeling to hear your engine sing. No offenses but i believe there is a lot more to learn out there though that deos not lead to sitting with tons of charts and ratios beside our driving seat.

Couldn't agree more with what you say.
Charts and printed guides will not help.
Learn to LISTEN to your car; it pretty much TELLS you how it is feeling.
Keep it 'singing' fit!

Quote:

Originally Posted by gemithomas (Post 605934)

:Shockked: So sorry. Did not notice that the alignment had gone haywire.

THis is the Speed at each gear that is recommended. GOt it from an old website when the adventure 1.6 was launched.

Gear_________ km/h
1 _____________ 7.7
2 _____________ 13.95
3 _____________ 20.34
4 _____________ 26.85
5 _____________ 33.55

I tried this out. And guess what you would be changing gears just below the 1500 rpm mark. And you wont feel that the engine is strained unless you are fully laden or you are going up a slope. Guess thats how turbosam manages to get these astonishing figures from the FIAT 1.6-es. But its quite difficult. You need to get used to such sedate driving. Turbo SAm. Is this your secret style of Driving?

On the other part. I read another thread where it is suggested that you zoom up in full speed till you reach the 5th gear. THe claim was that by doing so you are in the lower F.E mode for the least time and thus efficiency figures can be maximised. For example if you shift ot 5th at this 33.55 kmhr. You will be pressing the accelerator for much more time till you reach around 60km/hr and then only you might be driving with minimal acceleration. But in the other case we just zoom to 60 in seconds and then use minimum acceleration. Well That too seems sensible:)

i have never tried that way! i change much later<though i dont look at the needle>, i change when the engine tells me to change<not urges or begs!!>
generally with hi powered petrol engines u can pickup the speed quickly with wider throttle opening <still i dont zoom>. once u attain the desired speed u just coast in minimum accelerator which barely maintains the desired speed .
it takes lot of power to make one tonner move and reach 80kmph <acceleration>--- then it takes very little power just to maintain the velocity<0 acceleration>as its inertia has stored a lot of energy<mass*velocity>
thats why powerful engines with taller gear ratios give fanstatic crusing speed , on demand acceleration and great milage.:)

Quote:

Originally Posted by esteem_lover (Post 608881)

In that case, who would take care of the oil companies then ? Maybe they will start selling more coolant than petrol ? :)

what/why manufacturers dont do may have hundred and one reasons, what the basic laws of physics,hydraulics and fluid mechanics tell us matters.
hotter air will give lesser mass of air inside the engine , but will be able to extract more out of it .
production vehicles have to accept many compromises .more we understand them , more we can use them for our future projects!

Quote:

Originally Posted by gemithomas (Post 604573)

Just found thse specifications for the FIAT Adventure 1.6

Gear km/h
1 7.7
2 13.95
3 20.34
4 26.85
5 33.55

5th Gear at 33km/hr!!! Isnt that a little too low?

this is the ratio per 1ooo rpm it means in first gear it will attain 7.7kmph :) per 1000rpm
so at 3000 rpm it will attain 33.55*3 =99kmph in fifth gear!
thats the way the velocity ratio expressed in automobile engg!:rules:

Quote:

Originally Posted by ram_hyundai (Post 622428)

i am having a verna vgt which gives me 15-16 kml with a/c combined driving cycle .it has done 20000 km and latest tank full to tank full gave me 12 kmpl.

ram

Hi ram! That's a good FE figure for a Verna VGT, always depending on the traffic conditions.

Now,

Quote:

the a/c is super cool and i have noticed fumes -like fog comming out of the a/c vents .can this be an issue.

This is nothing to worry about. It happens when the compressor is frozen. Hyundai's a/c compressors are very powerful.

When the a/c compressor gets defrosted, that is when the compressor is turned off for sometime it'll be good again! No worries!

cya
A

Quote:

Originally Posted by Absar (Post 622738)

Hi ram! That's a good FE figure for a Verna VGT, always depending on the traffic conditions.

Now, This is nothing to worry about. It happens when the compressor is frozen. Hyundai's a/c compressors are very powerful.

When the a/c compressor gets defrosted, that is when the compressor is turned off for sometime it'll be good again! No worries!

cya
A

the fumes are due to condension of the moisture present in the cabin air.a/c compressor should never get frozen!
if u mean the cooling coil<evaporator in auto lingo>is freezing , then the a/c grill temp should be measured at first speed .at 50-60 kmph to check the a/c cut off function . if its not cutting off much below 0 deg centigrade then the thermo-switch/ice sensor should be checked, resetted as iceing on the evaporator coil hampers the cooling ability of the a/c system. :)

before any rocket-science techniques are applied, there is a very simple technique to get really great FE. which is to anticipate while you drive remembering that computer cuts-off fuel if you don't press accelerator pedal while in gear and rpm is more than idle rpm.

- whenever you have to slow down (speed breaker, signal, corners, etc.) do it gradually in gear by letting off the accelerator instead of accelerating and then hard braking in the last moment.

- whenever you are going down a slope, shift into the highest gear that gives adequate speed without pressing the accelerator pedal.

- turn off engine if the idle time is more than 60 seconds, remember that coasting in neutral or idling consumes fuel

hi , im from chennai and drive a 87k kms zen 2003 mpfi . before 1 year the fuel economy was 14kmpl with a/c and 16kmpl without a/c & now around 10kmpl so i dont drive with a/c these days and without a/c i get 13kmpl.can u help me ways to increase the fuel economy.
car running with knn air filter,engine decarbonised,fuel injectors cleaned,and regular servicing at 4k kms..
recently had a problem with the car>>engine gets off when changing gear(down shift) but rectified(it was due to loose connection in ignition cables) im feeling vibrations in cabin(since few days only) and got the engine rubber hoses replaced,the vibrations hav decreased a litttle but can still feel it. how to prevent it ?
plz help .. please:

Quote:

Originally Posted by androdev (Post 622987)

thats right , the fuel cut off rpm is different for each e.c.u.manufacturer.and it varies with models too .
for fiat palio the conditions are-- more than1700rpm+ accelerator pedal released completely+coolent temp above 50 deg c+battery voltage above12 volts+car is an gear<transmission engaged>
the fuel injection resumes as soon as the rpm drops below 1100 rpm:)
more u know the ruling and over-rulining parameters of the programming more u can use it for the desired goal.
coasting in neutral sure consumes pertol but it keeps the brake booster vaccum maintained.
closing the accelerator completely+keeping the car in gear is a great way to control the car in gear but
1>if your car is a carb version and if it doesnot have a fuel cutoff circuit like uno 1000, it will just gulp lots and lots of fuel because carb doesnot have a closed loop system, it works on venturi effect. more the pressure difference between the fuel in the float bowl and the jets in and around venturi more the petrol is sucked<or pushed by the pressure diff>in the engine.
2> when the car is coasting in gear+accelerator off position, the very high vacuum in the engine<i should be saying cylinders and combustion chambers>sucks a lot of oil from the valve guides and around the oil and compression rings.
so every thing has pros and cons , use them judiciously and reap the fruits!!

Quote:

Originally Posted by yasw_anth (Post 623097)

if your zen<4cyl> is a mpfi one then the engine should not die even if two cylinders die!

i think the problem of valve timing missalignment is the culprit.
get the timing belt replaced if not done already<generally 3 yrs or 50 k kms by belt mfg. quotes> and get the timing set perfectly preferably with the dial guage.
get the wet any dry compression checked .
then get the valve +tapette clearance adjusted WHEN ENGINE IS COMPLETELY COLD<AT LEAST 6 HRS IN OFF POSITION>
then check out the fuel return pipe function.
. fit the stock air filter . reset the ecu . assuming all the other things are good u should be getting better milasge than the new one <factory zens come with valve timing wondering +/- 5 deg >
NEVER EVER DO ANY chemical DE CARBONIZING AND CHEMICAL FLUSHING TREATMENTS they just screw the engines.:Frustrati