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19

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 ...


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

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. ...


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

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 ...


5

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 ...


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 ...


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

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 ...


3

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 ...


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

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 ...


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 ...


1

You don't need to worry about the RPM, just what the engine is capable of putting out. Engine 2 has more power, but together with differences in gearing and everything else, the fact that it does more RPM doesn't mean much. It could just be that the engine puts out about the same force as car 1 (Torque) but turns slightly faster therefore it has slightly ...


1

The deciding factor of an engines output is BMEP. Brake mean effective pressure. The dimensions of the engine components such as crankshaft throw, cylinder bore diameter and stroke will decide the BMEP. Further consideration would be volumetric effciency, ignition timing and the number of cylinders. An engine may be designed for economy, or power, or simply ...


1

Without being able to test directly, I can't be sure, but I think you have two problems. One is the ignition switch - the cause of starting issues, loss of electrical in the car, smoke from steering column all seem like they probably come from that. The loss of lines and weird display on your odometer sounds like an issue with the cluster, but will probably ...


1

The Forte LX mode uses a cable setup to work the door locks. While the EX uses rods. It is possible but, it would take some work to figure out a way to connect the door handle (interior) to the lock assembly. Next you would have to find a way to provide these locks with power since the harness is not the same in both models. On the software side both Body ...


1

A difference in design and efficiency. More BHP can be made with less torque simply by spinning it up to a higher RPM. Torque has a much greater correlation to engine size than BHP. Some examples: 6 cylinder, 540cid Lycoming IO-540 makes 300 BHP @ 2700 RPM. It requires something in the area of 600 lb-ft of torque to do so. My MUCH smaller 4 cylinder, ...


1

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.


1

After installing high wattage stereos with stock alternators, I have burned out alternators in less than 30 minutes, and I have also had them last months. It would be prudent to plan for an early failure.


1

It takes a specific amount of energy to accelerate a specific amount of mass to a specific speed. So just looking at those factors, you'd be right to assume that it matters little how quickly you accelerate said mass. But that's not how the real world works. The problem here is that combustion engines and the many things we connect them to are astoundingly ...


1

It might help if you give a little detail about your car generation or made year, since there might be variation on power steering system. Does the car manual or auto transmission? Is it share power steering fluid with clutch fluid, leak might occurred at clutch cylinder where you might did'n look at. Edit: read the problem description again and found that ...


1

As suggested, you need to put a flat head screw driver near the back edge of the lens and gently pry it off. Then you should be able to pull the lens out of the housing to remove it. This video might help: http://www.youtube.com/watch?v=vRPv4aVg9b8


1

Try to follow the positive battery cable from the battery to the next connection. It may be the starter or a post mounted to a power distribution block in the engine bay. Check that connection for tightness and corrosion. It is possible (I had this happen in my truck) that the battery terminal to cable connection is bad. In my case it was the old molded lead ...



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