27
votes
Accepted
Why would I want to measure torque while loosening a bolt or nut?
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 ...
- 2,311
22
votes
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Why tighten down in a criss-cross pattern?
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 ...
- 24.8k
19
votes
Accepted
When is a cold air intake system beneficial?
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 ...
- 24.3k
18
votes
Torque wrench or impact gun on large bolts
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 ...
- 153k
16
votes
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Is each turn with a beam torque wrench additive?
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!
- 7,047
15
votes
Accepted
Does using a ratchet size adaptor on a click-type ratchet wrench reduce the applied torque?
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 ...
- 266
14
votes
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what damage or extra wear (if any) is caused by turning over the engine while in gear (manual transmission)?
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 ...
- 311
14
votes
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What fasteners should not be loosened using an impact wrench, and why?
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 ...
- 39.1k
13
votes
Why tighten down in a criss-cross pattern?
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 ...
- 12.4k
12
votes
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Torque wrench or impact gun on large bolts
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 * ...
- 235
12
votes
I stored my click torque wrench in a mid-high setting. Is it ruined?
If you have one of these, you could easily test it yourself. I admit: this is not the most accurate way to measure the callibration, but it's probably the easiest way to give you a rough idea.
(Image ...
- 1,344
10
votes
Accepted
Measuring Horse Power and torque without a dynamometer
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 ...
- 13.3k
10
votes
What is the difference between torque and horsepower?
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 ...
- 39.1k
10
votes
What is the difference between torque and horsepower?
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 ...
- 28.7k
10
votes
Accepted
Horsepower at wheels calculation
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 ...
- 7,047
10
votes
Accepted
Impact sockets with a Torque wrench reduce accuracy?
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 ...
- 34.6k
10
votes
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Can I use a 15lbs torque wrench for 13lbs spark plug job
While it most likely will be OK, it is not worth the risk. If you do over torque the spark plugs and strip the threads you will regret it because it will be a big job to get it fixed.
Most mechanics ...
- 24.8k
10
votes
Can I use a 15lbs torque wrench for 13lbs spark plug job
The lower and upper ranges of the torque wrenches are generally unreliable.
With a bit of bad luck the deviation of the torque wrench is too large for the threads.
I'd consider getting a smaller ...
- 8,448
9
votes
When is a cold air intake system beneficial?
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 ...
- 781
9
votes
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"Always Replace" (torque-to-yield) Bolts
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 ...
- 153k
9
votes
Are there "standard" torque values for fasteners?
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 ...
- 153k
9
votes
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Why do service manuals specify a range for torque? Are there any reasons for being at one end or the other?
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 ...
- 12.4k
9
votes
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How many times can you go through a torque sequence when installing heads? I'm worried I messed up and should try again but don't wanna make it worse
Considering you have torque to yield (T2Y) bolts, once torqued through the angle sequence, you're done. If you remove the bolts, you have to start over with new bolts. T2Y bolts are one and done, ...
- 153k
8
votes
Accepted
How do I find out the proper torque number that I need to apply to an oil filter?
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 ...
- 13.3k
8
votes
What is the difference between torque and horsepower?
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.
...
- 1,935
8
votes
Accepted
What is the maximum torque a 1/2 drive can withstand?
Good question, while we probably can't just ring up a tool manufacturer and ask, we can derive it with some accuracy:
Maximum socket size I can find for 1/2" is 36mm, that translates to an M24 fixing:...
- 611
8
votes
Why tighten down in a criss-cross pattern?
Cross fastener tightening accomplishes:
It keeps the components being fastened aligned, and not cross mounted. This is a particular risk when a component is interior to a flange.
It helps keep the ...
- 2,115
7
votes
When is a cold air intake system beneficial?
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 ...
- 39.1k
7
votes
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Will increasing line pressure increase torque capacity?
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 ...
- 16k
7
votes
Accepted
What is the difference between torque and horsepower?
Power <-> torque relation
In general, the relation between power an torque is a simple formula:
Power[kW] = Torque[Nm] * RPM * π / 30,000
which means that you can always calculate the one curve ...
- 7,047
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