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30

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 ...


17

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. ...


16

Does this mod ever give a measurable increase in power? tl;dr: yes, sometimes it works well. But... Your picture is a good illustration of some of the problems with just saying "cold air intake" and expecting that to mean the same thing to all people. Let's break down the pieces of the puzzle and talk about how those might help or hurt: Filter: notice ...


16

That is a great question. I believe the true answer here is "it depends". Like so many other things you can do with your vehicle, if your vehicle cannot use the higher octane fuel, it won't benefit from it. Something to remember about octane ratings is, the higher number does not mean it is more energy dense. The higher number indicates the fuel is actually ...


12

Some things to check in order of likelihood- Check the battery connections are tight. A loose connection may prevent your car from starting, even when the lights, radio, etc., may seem to be working fine. The battery may not be fine. Lights are not high load,so having the lights work is not an indicator of how healthy your battery is Starter motor. ...


11

The power losses in a MT are primarily do to friction. Everything in a MT is positively locked together, meaning there is no slip anywhere. Beyond friction at least one of the rotating assemblies is partially submerged in the gear lube to provide splash lube for everything else. Stirring the fluid looses power. In an automatic everything I just mentioned ...


10

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 ...


10

There's an app for that! Basically if you can constantly measure the acceleration of your car, you can calculate horsepower and torque. I know I have seen advertisements in car magazines in the past for devices you would sick to the windshield, but since smartphones are so widespread and have such advanced accelerometers, Apps have taken over. I don't ...


9

Intake manifold runner length is the linear distance from the inlet port (the face of the head) to a common point shared by all cylinders. Depending on the throttle position this could be the open atmosphere (if each cylinder has its own throttle butterfly) or a plenum (if they share a throttle body). The intake runner volume is the volume of that section ...


9

Horsepower is how much power the engine can produce (how much work is done in a given time), wheras torque is the amount of turning force it can make (how much work is done). The two are quite intricately linked, so you can't have one without the other. You'll need to think of a few physics equations: Force = Mass x Acceleration Power = Work Done (Torque)...


9

Torque is work, horsepower is work rate In the context of engines: Torque indicates how much load an engine can carry for a certain distance in a certain amount of time. Power indicates how fast the engine can move that load over that distance. Some other things that may help to explain the difference between the two: Torque is what accelerates a ...


8

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 ...


8

The point is to feel like you've done something cool to your car and freed it from the shackles of The Man/the OEM intake. The primary benefit of Cold Air Intakes is to the bank account of the kit manufacturer, the secondary benefit is your car making a nicer noise, if you like the sound of an aftermarket intake. There's been a few debunkings of CAIs over ...


7

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 :...


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

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 ...


7

You should not incur any issues using a secondary battery with a battery isolator. It will not cause any damage to your alternator. For your edification, it won't be using wasted energy, but your engine will probably using a tad more gas to operate the alternator, which will have to do more work. On a side note, you might want to rethink exactly what you ...


7

It depends. Just because an intake can flow more air mass doesn't guarantee that the engine will utilize it. The intake is part of a system of components. The engine produces power by managing air flow into and out of the combustion chamber. There are usually other actors involved: Intake side. Carburetors, throttle bodies, intake manifolds, intake ...


7

Torque is the amount of force exerted by your engine at a particular RPM. In two cars with equal gearing and in the same gear, a car making twice as much torque will accelerate exactly twice as fast. Horsepower is calculated from torque and RPM. A given amount of torque at a low RPM equals less horsepower than the same amount of torque at a higher RPM. ...


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

Cool project! I know that the oil pump on my BMW is a chain-driven, positive-displacement gear-pump. My only concern with using an oil pump is that the internals can be prone to rusting, so either you'd want to coat/plate the vanes before use or add coolant to inhibit rust formation, but the oil pump should suit your needs. @Paulster2's suggestion of ...


6

Engine control systems in typical cars do not generally change the spark advance to add more than expected, the engine is designed to run at a particular efficiency for a given octane, so changing it from whats specified by the manufacturer isn't a good idea. If there is sub optimal conditions and the engine management detects a problem, fuel mix or knock ...


6

Two great comments already; couple of things to add. The reason why we have Octane types is because the lower-octane fuels tend to ignite at lower temperatures (ie. hot metal parts inside the combustion chamber, rather than the spark plug firing) or lower compression pressures (ie. the compression fires the engine like a diesel engine works). The octane ...


5

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 ...


5

Have the battery load tested. I've had several batteries go dead in the same manner: dash lights working just find until you turn the key and it all dies.


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 ...


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

I would like to add two valid points to this discussion as well: 1) When producing engines like this which produce more power with lower CC's, they won't be as smooth as their bigger naturally aspirated predecessors. They will have to rev higher just to produce the same power. So lets say you are driving at 70 MPH with a 5.0 V8, you could comfortably ...


5

Before I begin I must say that any accident of any degree cannot be diagnosed on-line and definitely needs to be taken to a mechanic for through inspection. However , based on your description I have a few points which might be helpful. If your exhaust got louder and you experience loss of power check if the exhaust is not damaged, If it has cracked then ...



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