the mitsu 4g18 engine are better for city driving. this is known for a very long time d. the campro are meant to be driven in a more sporty way. its just the way it was design.

3. An engine is most efficient at peak torque. At this point, you are getting the most power from your engine compared to fuel being consumed. Your statement that a car running at low rpm would consume less fuel is misleading. Assume 3 identical cars heading to the same destination. 1 fella drives at a very low speed (60kmh=2000rpm), the 2nd guy drives at the speed that matches peak torque (120kmh=4000rpm) while the 3rd guy drives flat out (160kmh=6000rpm). When compared, most likely the 2nd guy will get the best fuel consumption, because he keeps his engine running closest to peak torque. But even this analysis is still subjective, i'm just giving a best case scenario. It would be best to test each car individually to find the point where it gives best FC, but chances are high this will be somewhere near peak torque when at constant speed.

You're being rather unfair to the campro, as i mentioned...it has a lousy torque curve for a engine suitable for city driving. Iinm, it has a slightly higher than average maximum HP for 1.6L class and from what I've seen, its quite good on the highway.

I don't think u understood my analogy. I in fact said that car number 2 (at 4000rpm which is nearest peak torque) would probably get the best FC, simply on the assumption that at peak torque, you get the best power for fuel consumed.

i think u got me wrong.. wut i meant was tht the torque peak much later at the band.. not earlier like 4g18. btw.. all NA cars need to rev higher to draw out the power.. im not a car idiot..

As i know the horsepower constantly increase when RPM roll up,n normally would achieve peak HP at 6-7K RPM.
Is tat means for fastest acceleration,we should drag to 6-7k RPM b4 shift to higher gear?

For example:
we drag the 1st gear to 7k RPM to archieve Peak Horse power,
Then shift up to 2nd gear n the RPM dropped to 5k RPM,then we drag again to 7k RPM to Peak horse power,
N repeat n repeat...
So in this way we can maintain the peak HP,n btw Fastest acceleration?

I dun think all these make sense,torque is the force to twist the wheel/tyre,meaning torque high=faster acceleration,
Peak HP should be the total force created at by the car wheel at maximum RPM,meaning a metric for topspeed.

torque is the force to twist the wheel/tyre,meaning torque high=faster acceleration,
Peak HP should be the total force created at by the car wheel at maximum RPM,meaning a metric for topspeed.

Then blame the transmission not the engine Poor pairing of transmission with engine will make any engine no matter how good perform poorly

cps not that bad also if you ever try b4, the performance have a drastic improvement compared to campro without cps.

and transmission does matter alot. first generation gen2 with automatic gearbox just simply lower the gear when u approach a slightly downhill, and when u floor the acceleration pedal it takes much longer time to lower the gear. dun you think it ll affect the performance and fuel consumption alot.

Lets say for car 1,torque peak at 2500RPM,and slowly drop from 2.5k-4k,n a drastic drop after 4k.
Which way should be better?

1)drag to 4k RPM n then shift to higher gear,n it should drop back to 2-3k RPM.

2)drag to 6k RPM(closest to MAX HP)then only shift gear,n should be dropped to 4-5k RPM.

Seriously do u guys think,if i go to a car showroom,do i have the RIGHT to ask for their engine torque curve/HP curve chart?
Or any other way to know a car engine performance more detail?

Buy car not = buy something in pasar le

Engine
In layman term, with fix fuel supply (maintain pedal position), a vehicle can travel at 100km/h (2500 rpm) on straight road, or 120km/h (3000 rpm) going downhill, or 70 km/h (2000 rpm) going uphill. Despite the different in speed and rpm, the engine actually consume same amount of fuel (in reality this might varies a bit, but this assumption is still generally true). What happen is that, the engine require less fuel to produce same amount of torque (during downhill) or more fuel during uphill.

Horsepower, on other hand, is the ability of the engine to response to fuel supply. (rate of energy release). An engine with high horsepower has the ability to response immediately to fuel, thus able to change its torque. By the chart, it simply means the ability to rev. If you notice, a car rpm increase faster when it approach peak hp, and fastest at peak hp. (We are unlikely to admit that it is fastest at peak hp. This is because hp drop after the peak hence it appear slow). Engines with VTEC, VVTI, CPS has higher peak hp at high rpm, this means driver will observe that the acceleration is highest when it reach peak hp.

What happen to campro engine, it has relatively acceptable hp chart (higher rate of energy release), which means angular acceleration (the speed rpm needle increase) is fairly constant. Because horsepower means the ability to change its torque, looking from the graph (campro), at 2000-3500 rpm, it means the ability to decrease its torque. This also mean it is less efficient in this interval. No wonder why campro owner complain about sluggish engine response. This effect is magnified during uphill. The dip in torque means it require even more fuel than other vehicle to carry itself uphill.

Back to motor, its high torque, low horsepower means it is good for road cruising, at constant speed. While for acceleration, the high horsepower engine comes in. The next generation of hybrid car will see the evolution of small cc engine (with high horsepower) and high torque motor.

How it is implemented, that require a new chapter of applied physic.

OK, let me try this on a more layman's term.

When a person lifts a dumbell with his hand, the maximum weight he can lift is the torque, while HP is calculated by (the weight of the dumbell multiply by the distance of the motion) and divided by seconds.

So guys, is that true?