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25

cc is the size of the engine, in cubic centimeters - literally the volume of the cylinders. A larger cylinder can ingest more air (and more fuel), thus converting more energy per cycle than a smaller one, so making more power - assuming all other factors are the same, and there are many factors that affect power output. You can measure it by a simple volume ...


11

What does the power at different rpm mean? Does it mean Car 1 has better power than Car 2 because it is at lower rpm? It depends. Or does the rpm not affect the power comparison? tl;dr: The rpm of the power peak affects the engine's usability for different applications. The "peak power" number is just one point on the power band of the engine. ...


7

How old is the battery? If it's the original one, it's probably just in need of replacement. 5-7 years is a typical battery lifetime. At the end of life, they will sometimes appear to charge, but die rapidly if not used for a few days.


7

tl;dr: Cold dry air has a substantial effect on horsepower. This can be confirmed through experimentation on any modern car. I can think of two scientific reasons as to why this may be: Increased air density Decreased humidity Yes and yes. You're already most of the way there. Let's take a quick trip to simplified theoretical model ...


6

Not sure what it "should" be pulling, but anywhere near a whole amp is way too much and will drain the battery in no time. Are you sure you tested right? Often the pull when you first connect the battery can be a lot higher than the steady pull since you might be charging some capacitors, etc. If it stays that high you definitely have a problem, possibly a ...


6

You should not notice any difference. Here's why: 1 hp = 746 W. This means that 60 W is 0.08 hp. The worst possible scenario from a load perspective is at idle. Assuming the engine is outputting a measly 5 hp at idle, the extra load would work out to 1.6 % of this value. The change in fuel consumption is barely sensible.


6

There are advantages, but also disadvantages to using a smaller turbocharged engine with a higher power output. The pro's of smaller, turbocharged engines: When not on boost (below e.g. 3000RPM) the engine uses much less fuel. turbocharged engines have a flatter torque curve, meaning they're working closer to optimal level throughout a larger portion of ...


5

I'm pretty sure "peak" means you can pull that much momentarily, but if there's a sustained load that high, it will trip the circuit breaker. If your vacuum is rated 550 watts, that's probably the sustained draw, and the power needed to start the motor is probably A LOT higher. I would just go with a sufficiently powerful inverter model that clips to the ...


5

Firstly, what car is it? (Make, model, year). Is the fuel smell more pronounced around the engine bay (suggesting a leak) or around the exhaust (suggesting unburnt fuel)? Shaking and low power suggests, as you suspect, that it isn't running on all cylinders (which would result in unburnt fuel coming out the exhaust). If it is only doing so when hot, my ...


4

The "swept volume" of one cylinder is given by : pi * r^2 * L r = cylinder radius (bore / 2 ) in centimetres L = stroke in centimetres Then multiply by the number of cylinders (they will all be the same bore and stroke) Example : Bullet 350 bore and stroke given as 70 mm ( 7.0 cm) bore and 90 mm (9.0 cm) stroke So : r = (7.0 / 2) 3.5 cm L = 9.0 cm Then ...


4

This is a little hard to answer without more information about the history of the car. My first instinct tells me, though, that you're just looking at a situation where a vehicle deserves some freshening maintenance. Here are some fundamentals worth checking: How is the air path through the engine? Remember, the engine is basically a big air pump: there ...


4

It says right on the webpage: Conventional all-wheel drive cars employ complex mechanical linkages to distribute power from a single engine to all four wheels. This sacrifices efficiency in favor of all weather traction. In contrast, each Model S motor is lighter, smaller and more efficient than its rear wheel drive counterpart, providing both improved ...


4

This is a great vehicle dynamics question that essentially has two parts to it: Is the motor able to hit top speed, 120 mph? Is the torque enough to accelerate it to top speed within 5 seconds? The motor in question Power : 1000 W (~ 1.36 hp) Speed : 3200 RPM Torque : 1.91 Nm Something interesting to note here is the apparent discrepancy between ...


4

Almost any amount of load you put on the battery is going to drop the voltage. How much depends on the capacity of the battery as well as the health. It would appear that 12.32V would put the battery into the 60% charge according to most of the State of Charge charts. State of charge charts are referring to open circuit voltage (without any load on the ...


3

There are two sides to the design and efficiency coin. As a rule of thumb, more modern motors would have better characteristics due to general improvements in manufacturing (machining tolerances are smaller, for instance), and engineering. Liquid-cooled motors are more efficient, as a rule, than air-cooled, and so forth. However, there are also other ...


3

The Megane Mk1 has a coil pack per spark plug - they sit in the engine block just above the plugs themselves. One of the coil packs may be faulty causing intermittent spark at the plug.


3

This car will be able to go up and down reasonably steep hills, but it is not a powerful car, and it is definitely not an off road car. 650cc and 800cc engines are considered pretty small, but on hill climb vehicles the gearing can give you a lot of torque which will help you climb steep slopes. This car has gearing set up for city driving, so it isn't ...


3

If you put too much of a load on the alternator it will constantly max itself out as it tries to keep up with the demand. Running at max will heat up the alternator and eventually it will burn out. As @Brian pointed out, probably sooner than later. Most aftermarket audio systems that require higher amps also have high output alternators.


3

The general "rule of thumb" for horsepower ratings between crank HP (CHP) and rear-wheel HP (RWHP) is ~18-20%. An automatic transmission will be closer to 20%, while a manual transmission around 18%. As you stated, and for the same reasons, these are just a general guideline. If you have the CHP number available, multiply that number by .8. (ie: 450hp x 0.8 ...


3

The correct way to charge a battery is to apply a charging current of around 1.5-2 amps to a maximum electrolyte specific gravity, then to fully discharge the battery at a very low 1 or 2 amps, then to re-charge the battery at a low amperage again, then discharge at a very low amps again. This process should be repeated until the electrolyte specific gravity ...


3

There are several advantages to a lower displacement engine over a larger one. Firstly is weight, an engine of 2,000cc will weigh significantly less than a 3,000cc engine because it will have a smaller block, this in turn decreases inertia of moving parts (such as the cylinder head and cam shaft). Secondly we can factor in fuel economy, if an engine has ...


3

In addition to size, weight and fuel economy, a small, highly tuned engine is going to be much more ecologically friendly. This is because a large engine producing 350 bhp can do it without being highly tuned - fuel is unlikely to be fully burned, emissions will be higher than with a smaller engine which can burn fuel more fully.


3

It very well could be the battery has what is called a surface charge. The battery will have enough power to start the vehicle, but if too much of a load is put onto it, the voltage will drop and not be enough to run the vehicle with or with out a good alternator. The battery will basically be sucking the alternator dry. When this happens, the wipers will ...


2

Better consider an alternator upgrade when it blows up. You'll probably be blowing it up pretty soon. :-)


2

The NYtimes recently published this article basically stating that the longevity of modern cars (2001 seems to fit into that) far exceeds that of the previous generation. It quotes a Ford person saying that a test F150 was stripped down after 250K miles and showed no engine wear. This would tend to indicate to mean that your car should not lose its pickup ...


2

It should not. There can be minor engine wear resulting in a very slight loss of compression, but that's usually offset by some parts being "looser" and having slightly less friction. Modern cars are designed to go 100k miles without even having detectable wear at all! Anything other than that is abnormal and is a symptom of some problem. Weak ignition ...


2

As you said the crux of the issue has to do with getting every last amount of energy out of a unit of fuel. You can consider this your total fuel efficiency. Accelerating your vehicle from rest to 60mph or 100km/h will require a fixed amount of energy based on the weight of the vehicle. (excluding wind, friction and rolling resistance). So you need to ...


2

Does accelerating faster worsen fuel efficiency? Yes. Now obviously when you accelerate harder, more fuel is being pumped into your engine, but you'll sooner get to that cruising sweet spot where fuel consumption is a lot less. So is the payoff worth it or not? No. This is easily measured via the OBD II port. For example, my Accessport ...


2

0.10 amps will kill your battery quick like, you should get it down as close to 0.00 amps as possible. My experience was that to keep the radio stations, etc. it takes about 0.01 amp on the meter. So yeah, you got something going on... In my case, it was the key lock light staying on and the door lights (or rather door light relays) staying on.


2

The diodes should work, but be aware that they will drop ~0.7V or so, so you'll actually get ~11.3V instead of 12V. If the radio is okay with that, and if you can dissipate the heat caused by the diode drop * current drawn (may be small, but must be known), then you're okay. It won't backfeed either source. If you don't want the voltage drop, then you can ...



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