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14

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: ...


13

Yes you should store it at zero, it weakens the spring. I would have it checked/calibrated to make sure it is still accurate.


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 ...


8

Nope, doing it with the wheels on the ground if fine, no need to lift the weight of the wheels. It's easier that way because the wheels can't turn while you are torquing the lugs.


8

Until the engine starts the only thing applying torque to the drive train is the starter motor, the engine itself is not providing any torque. Starting like this will not cause any damage to the drive train (except perhaps the teeth on the edge of the flywheel that the starter motor engages with) but it does put excessive load on the starter motor and it's ...


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 ...


8

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 ...


8

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 ...


7

Torque is how strong your engine is and Horsepower is a measure of how fast it can use that power. That is why a Diesel engine with 400Nm of Torque cannot out-accellerate a petrol car with 400Nm of Torque. Horsepower is calculated by multiplying the amount of torque by the RPM of the engine (and dividing by 5,252. But that's not important here). Because a ...


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 ...


6

I would not back the nut off to align the nut with the cotter pinhole. Doing so can result in the taper between the knuckle and the tierod becoming loose. The cotter pin would keep the nut from backing off but it would not prevent the tapered shaft of the tierod from spinning in the tapered hole of the knuckle. As @MikeSaull has suggested lube the threads. ...


6

In an ideal world where time plays no issue you would torque all the lug nuts to 1/3 of the reccomended torque in a crisscross pattern. Reset the torque wrench to 2/3 of the torque spec and tighten again in a crisscross pattern. Finally set the wrench to 100% of the torque spec and do the final tightening. After 50 miles recheck the lugs with the wrench set ...


6

90° = quarter turn. 180° = half turn. It's alright if you are off a few degrees. I typically start with the breaker bar perpendicular (straight out) and do quarter turns, or have it straight off to the left. Just keep yourself parallel or perpendicular to where you start. DO NOT USE A TORQUE WRENCH. It's bad for the torque wrench to turn after its ...


5

I believe you are confusing torque (TQ) and horsepower (HP) terms here. HP is a mathematical computation based on TQ. You can derive a HP number by increasing the rotational speed up/down depending on what you want to achieve. Weight of a vehicle will have no affect on either. As mentioned in the comments, TQ output (at the wheels) is greatly affected by ...


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

Most oil filters have instructions for tightness printed on them, and they normally read like: Tighten by hand until base contact, and then tighten an additional 1/4 turn. I don't recall ever seeing torque mentioned, because the filter housing relies on the rubber o-ring seal rather than mechanical tightness to seal in the oil. Too much torque will ...


5

The basics are quite simple. The motor generates a certain torque N and a certain power P at a given RPM. Further more, the relation between power and torque is: P = C * N * RPM where C is a constant to convert all that odd units. For N, P in SI units, it is C = pi / 30 Neglecting any losses, Power is conserved from the motor to the wheels so you ...


5

I think I got this. someone help me verify... So I watch the tach and speedo to determine MPH per 1000 RPM in higher gears (3rd,4th,5th). On my car its about 10, 15, 19.5. [tire diameter (in inches)] * [pi] * [1/(gear ratio * final drive ratio)] / [in/ft] / [ft/mi] * [RPM] * [min/hr] = MPH constants pi = 3.14159 in/ft = 12 ft/mi = 5280 min/hr = 60 ...


5

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. ...


4

I think a click wrench is an automatic torque wrench. I think an automatic torque wrench is any wrench that stops applying torque once the specified torque is reached. This could be achieved in a number of ways. Whether it uses a clutch or spring and ball is irrelevant. A click wrench will briefly stop applying torque once the specified torque is reached ...


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

The engine torque produced is a function of the amount of air ingested and the air/fuel ratio combusted in the cylinder(s), combined with 'static' variables like the compression ratio, bore/stroke, crankshaft design, intake length, cam profile, intake and exhaust sizing, etc. With all the other parameters now static (non-variable) once the engine is built ...


4

Theoretically yes, practically it's not that easy. Line pressure is just one of the components that contribute to the torque capacity of the transmission. First, it's not the speed of the application of a clutch but the holding strength once the clutch is applied that contributes to strength. In this respect higher line pressure will give higher torque ...


4

There are not calculations. The car has a list of PIDs that the tool checks. The readiness monitors are a set of tests that the car runs including but not limited to EVAP, EGR, CATALIST, O2, FUEL, COMPREHENSIVE. When the codes in a car are cleared all the PID values for the monitors are cleared. As the car completes and passes the necessary tests it will ...


4

Almost never? Mainly because they're really a 'hot air intake system'. This is especially true for cars using forced injection due to the high under-hood temperatures. If you want to reduce intake restriction look into a less restrictive 'panel' filter like a K&N. Even then, it really only matters if your car is intake (vs exhaust) limited and your ECU ...


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

Torque in a motorcycle The piston moves up and down, and the force for that comes from the fuel that is burned. Connected to the piston is a rod, the connecting rod, and that rod is connected (with the ability to turn) to the crankshaft. The distance between the pedal to the rotation point is comparable to the distance between the crank and the middle ...


3

horsepower = (torque * RPM) / 5252 always. Typically engines have to suck in their air and fuel so they can only suck in an optimal amount in a certain range. With a turbo you are forcing the air in, so the engine can make more torque over a wider range. If there is a max torque the manufacturer wants to set (for torque limit on the ...


3

From Wikipedia: Brake horsepower (bhp) is the measure of an engine's horsepower before the loss in power caused by the gearbox, alternator, differential, water pump, and other auxiliary components such as power steering pump, muffled exhaust system, etc. Brake refers to a device which was used to load an engine and hold it at a desired rotational speed. ...


3

I would use some anti-seize on the threads then tighten it to torque spec. If it doesn't line up then I would tighten it until it does. This is just what I would do. If it is a weak bolt or a really bad place for the threads to strip then I would just loosen it until it lines up. Once the cotter pin is in it shouldn't go anywhere anyways.



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