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25

Sometimes you want to measure breakaway torque. This can tell you if a fastener has started to loosen due to vibration, or was over-torqued and the bolt/stud may have stretched or weakened, or the fastener was cross-threaded and need to be replaced. Note that breakaway torque values will often be higher than the stated torque spec, as the breakaway torque ...


20

There is more to it than just a "criss-cross" pattern. You should also work your way out from the middle in stages of bolt torque. If you imagine tightening a cylinder head down starting at the two very ends. You have a gasket between the head and the block that doesn't really want to be crushed. When you tighten the ends down, the middle of the head ...


19

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 ...


18

To answer your question directly, this is a "standard practice" but a VERY poor one. Getting the correct torque is by far more important than getting it done quickly. With the axle nut it is imperative you tighten it to the correct spec. If you tighten it too tight, the wheel bearing will self destruct within a few hundred miles. Using an impact gun can ...


16

If that would be possible, every 3-year old could fasten the bolt. He just has to try 100 times with 0.5lb-ft. You have to apply the full 50lb-ft, regardless of the torque applied before!


14

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 ...


14

No, it won't reduce the torque. Torque is equivalent to radius x force. As long as A, the force is applied at the same distance from the nut/bolt that you're tightening and B, it's applied in the same direction then you'll be applying the same torque. An adapter (especially so short) shouldn't have a noticeable effect on the direction that you're applying ...


13

As the name suggests, impact wrenches have the ability to impart high amounts of momentum change. The delivery of this momentum change is hard to meter, so it is quite easy to damage: soft metals and alloys thin threads (both male or female) This applies to both loosening and tightening. Take the example of spark plugs and head bolts, which screw into ...


12

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 ...


12

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 ...


12

Neither. Just get a 1m long bar (by extending a breaker or similar), stick it on the nut so that it is horizontal and simply hang 250N of mass at the end of it: (*) 250N = 56.2 lbs = 25.5 Kg 250N * 1m = 250Nm Rinse and repeat until it hangs and doesn't tighten the nut anymore. The trick is to keep the bar horizontal, you'll likely need a 12-point socket ...


12

In general things should be tightened in stages with some sort of crossed pattern depending on the number of fasteners in the circle. Not doing so creates a bias that could result in false torque readings on the final fasteners. In other cases it can warp or damage the item being fastened, or perhaps prevent proper sealing of a gasket. Cylinder heads, ...


11

Torque wrenches are used for adjusting the specific tightness of nuts and bolts. They come with an adjustable torque setting which is usually in foot pounds (english) or Newton meters (metric). In automotive applications, most nuts/bolts will have a torque setting specified in the manual that when applied will give the exact amount of pressure needed to ...


11

Double checking your torque is never a bad thing. The only thing you lose is a half second of your time. Peace of mind is what it's all about. One of the reasons for doing this, though, might be when you are torquing, the fastener itself becomes slightly bound up, not giving a perfectly correct reading. By double clicking, you are allowing the fastener to ...


10

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 ...


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 ...


10

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)...


10

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 vehicle ...


10

TL;DR The problem you are encountering is the limited resolution of your speed plus fluctuation plus slightly different approaches to calculate power. And finally, you have to think about the term power at wheels. What exactly is power at wheels? I would say, this is the tangential force applied by the wheels onto the street (i.e. the force that's pushing ...


10

Short answer : no, you can't apply the force suddenly enough to make the socket flex to make a difference - what can skew the readings or, at least, the torque applied is friction between the nut or bolt head and the surface it is mating to. That is why some manuals state the type of lubricant to be used between the nut / washer etc.


9

If I'm using anti-seize, I still don't reduce the torque on the fastener. I use the amount specified by the application. The reason being is, in most places where torque is a factor, getting the clamping load even is more important than is the factoring in the amount the lube will reduce the need for torque. The anti-seize will work as a lubricant on the ...


9

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 ...


9

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 ...


9

I cannot tell you directly if the bolts you are using are Torque to Yield (TTY or T2Y) bolts, but if Bently says to replace them, you bet I'd do it. What are three bolts in comparison to the well being of your family and yourself, not to mention those around you should any of these bolts fail? As for T2Y bolts, here is what Fel-Pro says about them: T-T-Y ...


9

tl dr: No. There are too many variables. There are two things at play when tightening a fastener for an oil pan: How much torque can the fastener actually handle? How much squish can the gasket handle before it doesn't seal. Torque values for bolts will differ, due to size and hardness. An ARP bolt of any size will handle way more tensile load than its ...


9

No, I think it has more to do with an expected range, given the vast number of torque tools, operator technique, and the distinct lack of calibration of most folks' torque wrenches. (And I am as or more guilty than most... my elbow used to click +/- 2 lb-ft. Now, after four decades of wrenching on things, my elbow clicks just attempting to get out of bed ...


8

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 ...


8

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. ...


8

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 ...


8

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 ...


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