CHIP Tunning to decrease performance

[Balal]

Hi there,
I was wondering, if there is any such thing as tunning of car ECU to decrease car performance and hence increase fuel consumption and less exhaust emissions!? handy for city driving !!!!!

Any input much appreciated!

Balal

p.s. I am not wanting to personally do it. just curious about it!!

 

[television]

The car is only economical when the engine is running at the peak of its torque.
If you retarred the engine, the head will over heat, if you advance it it will pink and need a higher octane fuel,, if you reduce the amount of fuel it will have no power.

I bought a recon ford 3 liter engine once, I put it in, it started and ran like a sewing machine, problem was that it had no power what so ever, it would not even pull away in first. The recon guys had fitted the wrong pistons (1" too short) and there was no compression, so if you reduce the compression the power goes down.
I fitted a car radio many years ago into an Austin A35, the guy came back the next day saying that the car did not go very well since the radio, I had taken off two spark plug leads to fit the supressor and forgot to put them back, but the car did drive.

Cars are made that shut down some cylinders for town driving.

Malcolm

 

[jberks]

The problem with town driving is not so much the engine design or efficiency, but the energy required to exceed the inertia from stationary combined with the fuel usage at idle.
Clearly a bigger cc engine needs more fuel to idle, so on that basis, a smaller engine has better town mpg and lower emissions. However, away from idle, larger engines can be more efficient if their lower rev torque better matches the requirements. Hence, a C180 is no more economical than a C200 overall, but the 180 will be better at idle and the 200 away from the line.
But no - there is nothing they can do with the ecu. All the performance boys actually do is increase the fuel flow. I doubt you could decrease it much as the manufacturers will have already done this as much as is safe.

 

[Balal]

Thanks for the reply ...

Well! my understanding of car ECU in present car internal combustion engine with fuel injectors (not the old carburetor ones) is that ECU monitors the exhaust emissions from oxygen sensors and senses the air coming in through air intake sensors and then controls the fuel injectors to inject just right amout of fuel in cylinder for the engine, along with right spark timing to work!!! right?!

and in chip tuning to increase performance, this ratio of oxygen and fuel in cylinder is increased to give higher combustion thus increase in bhp. ofcourse the spark timing is increased by ECU as well to support this combustion at every throttle.now, if this ratio of fuel, spark ratio and compression ratio is decreaed at times, would that not make car work at low revs in city ?!

p.s. car manufactors have this lookup table in CAR ECU with reading of optimal fuel to air ratio and spark timinngs built in it (that lookup table readings are modified by chip tuners- (correct me if i am wrong please)) !! they can have more than one type of look up tables but then the price of ECU would go up and probably they would have to employ a better and expensive microprocessor to do the job! I think in F1 cars, they have these chips that you can change performce while car is moving ... is that right assumption ?!?

 

[Glenn Smith]

modern engine actually run too lean to be as efficient and economical as they could if the designers didn't have emissions to deal with, most tuning chips work by increasing fueling to a point where the emmisions are beyond the limits, although they may still pass an mot, this usaully makes the car more responsive, more flexible, more powerfull and probably more economical!!! other chips increase boost pressure of turbocharged motors with a corresponding fuel increase to give more power, again emmisssions may suffer,

 

[Balal]

modern engine actually run too lean to be as efficient and economical as they could if the designers didn't have emissions to deal with, most tuning chips work by increasing fueling to a point where the emmisions are beyond the limits, although they may still pass an mot, this usaully makes the car more responsive, more flexible, more powerfull and probably more economical!!! other chips increase boost pressure of turbocharged motors with a corresponding fuel increase to give more power, again emmisssions may suffer,

True! .... the turbo charger compresses air and puts more cold air (as it has more oxygen) to be burnt in the cylinder. so more combustion means more exhaust fumes. soooooo does that mean if the air going in and the combustion ratio is decreased the exhuast fumes would be decreased ...

(to answer jberks concern ) ... lower the bhp and torque to the point just right to move the car.....would that not be good in city for fuel and emissions <in theory> ?!? I couldnt understand what you meant by fuel consumption at idling? should it not be just be low to begin with just to keep engine working?!

 

[Jay Kilby]

i do not know what car you drive Balal but somebody has already mentioned that the chip tuning people alter the look up tables for the fueling and timing of a particular car. modern MFR's have to build cars that work in all world conditions and all the worlds quality of fuel. so they do not map a car to it's most effeciant. by fine tuning the ecu knowing you will only use the best fuel will optimise and engine and it's performance hence more bhp, responsivnes and most cases better mpg. by de-tuning a car the engine will not be at it's optimum you have to account for all driving circumstances. if you have brought a big engined car to run around town then perhaps you have brought the wrong car and should have brought a supermini that is desinged for the job, small car, small engine who's tourqe is low down the rev range making standing start's easy. these cars are usually rubbish on the motorway and at 80mph (i know the limit is 70) would return a similar mpg to a 1.8 car.
lowering the bhp and tourqe would still reqire the same amount of fuel to make the bang strong enough to send the piston down the cylinder, you have to have a balance or you will end up with an engine that is a one trick pony only good at one thing like a hill climb car engine is set up to pull a car up hill so power and tourqe are usually lower in the rev range than say an F1 car designed to run on a relitivly flat circuit so power delivery is high in the rev range using the momentum of the engine to generate power and in comparison to BHP relitivly low tourqe.

hope that makes sence

 

[Jay Kilby]

Thinking about it to demonstrate a point get somebody with say a punto on a flat road hand brake of in netueral and push the car to a point were walking is easy while pushing. then get somebody with a big car like say C200 and do the same, then note how knakered you are after each push, this should help you understand why detuning a car would not help in city driving, because the engine would have to work harder to move the mass.

 

[Balal]

Thanks Jay Kilby...

well! The reason for asking this question is for pure research and development pruposes in academics. So the engine in question is large engine, and the idea is to de-tune it in city and super tune it on motorways and maybe have a setting in between it as well, thus development of car ECU thats reconfigurable at run-time!

I am reading about such ECUs now, but couldnt find if there are already such cars that have such ECU in them!! anyone kwows any car ECU that does it already !?

 

[Balal]

Thinking about it to demonstrate a point get somebody with say a punto on a flat road hand brake of in netueral and push the car to a point were walking is easy while pushing. then get somebody with a big car like say C200 and do the same, then note how knakered you are after each push, this should help you understand why detuning a car would not help in city driving, because the engine would have to work harder to move the mass.

i think i know what you trying to say....its like at say 1st gear, we use it to move car from stationary position and it has more power and high revs....but we certainly dont need that much revs to start moving slow in city center not unless you are starting a race at traffic light!

 

[Jay Kilby]

Balal,

interesting thought you have and i would say it can be done if enough money were available, we already have lexus and toyota producing hybrid cars petrol/electric!
there is nothing stopping you from running multiple ecu's that could be switched from within the car according to the driving conditions. however you would need to consider the fact that it is not all down to the ecu, on a normally asperated engine for example being tuned for hill climbing i would use a different cambs and valve clearances, carbs/injection than for a engine in a rally car. you need to understand the difference between the two power ratings on an engine namely BHP & Tourqe. in simple terms BHP delivers speed and tourqe gives you the ability to maintain speed under load a hill for example. if you take any car and hold a constant speed in a set gear at 40mph on a flat, then as you start to go up hill do not depress the accelerator it will slow down, how much the car will slow will depend on how much tourqe the engine is producing.
for your research i would have a look a honda type r engine they have effectively done what you are trying to acheive by using a clever variable valve timing system effectivly two engines in one. below 5000 rpm the car runs like an normal car being very efficiant around town with enough BHP and Tourqe being delivered low in the rev range. now over 5000 rpm the clever bits change altering the valve clearances and timing to deliver much more BHP (these engines rev to 9000rpm) also the peak tourqe moves up the rev range but does not increase as dramaticly as the BHP. so whilst these engines are powerful in BHP terms you have to work them to benafit fall below the 5000rpm and you have to wait for the system to kick in again.
so in theory you could change ecu settings on the fly but only within the paramiters of how the engine was constructed....it's intended purpose if you see what i mean. you may benafit by speaking to sombody at superchips they would be able to tell you how much you can use the ecu to move things around in terms of peak BHP and tourqe.
please keep me posted on your results.

 

[Jay Kilby]

i think i know what you trying to say....its like at say 1st gear, we use it to move car from stationary position and it has more power and high revs....but we certainly dont need that much revs to start moving slow in city center not unless you are starting a race at traffic light!

You are nearly there but i was refering to the engine, when you add gearing it is simply a way of increasing road speed, the engine is producing no more power, it is just the gear ratio is making the mass easyer to move. you could pull away in second but the load on the engine would negate what you are trying to acheive.
back in the late eightys.early ninety's f1 teams used a gear system that kept the engine revving at its peak power while the gearbox changed the the gearing. if you can imagine the gears on a push bike it essentually went up that but the engine revved and it's peak at all times. just something else to consider.

 

[Balal]

Thanks Jay for such a detailed answer...

Balal,

interesting thought you have and i would say it can be done if enough money were available, we already have lexus and toyota producing hybrid cars petrol/electric!
there is nothing stopping you from running multiple ecu's that could be switched from within the car according to the driving conditions.

Well! I can (or our lab for that sake) can only deal with ECU part of the engine (on chip system designers), so the only thing I can modify is the chip, we develop a single chip thats reconfigurable at run time so to give feeling of multiple chips each running separtly(keeping it non technical ) .... so my idea is to just have one chip that would be reconfigured when needed for differnt performces (without changing the air intake,pison displacemnt,exhaust system etc) ... would assume them to be optomised and compatible to run with low performance ecu settings ( like the limp mode in car).

for your research i would have a look a honda type r engine they have effectively done what you are trying to acheive by using a clever variable valve timing system effectivly two engines in one. .....

I am meeting the automotive engineers at the mechanical department soon to talk about their opinions about it, and what engine shall or can we alter performance by just configuring ECU. As I said, I can only deal with electronics of car that can be controlled by some chip or microprocessor etc. so have to rely on them for their input in someway..

so in theory you could change ecu settings on the fly but only within the paramiters of how the engine was constructed....it's intended purpose if you see what i mean.

finally this point of yours is what my whole research will be based on in this project (if i got the go ahead from the guys above).
as in worst case scenario, even if we cant de-tune the chip, we can always have a setting for normal (manufacture setings) aaaand the super tuned setting (that the tuners do with chip) for motorway driving!!!!

chipping (tunning of chip) is already done to increase performce, so thats do-able. I was hoping to get opinions on what de-tunning would do or its feasablity from everyones experiences.... sooooo once again Jay Kilby, Malcolm, jberks and Glenn Smith thanks alot. much appreciate your input .

Will update if it ever went any further thn a project proposal