How do engineers determine torque specs?

Begin with the formula T = K x U x D x P, where T is the torque, K is a standard representing 1.33, U is the coefficient of friction, D is the diameter of the fasteners, and P is the necessary preload.

Where do I find all the torque specs for my car?

Any repair manual specific to your vehicle (Chilton’s, Haynes, Motor, Factory manual, etc.) You can find them at most parts stores, you can check them out at your public library, you can find them on eBay and sometimes on craigslist, and you can download a pdf file from the internet, often free!

Do mechanics follow torque specs?

No matter the project or repair, if you are tightening a bolt, the bolt has a specific pressure at which it should be tightened. For some areas on the vehicle, not following torque specs isn’t a big deal; however, for certain projects following torque specs are vital. Torque wrenches ensure a proper seal that is level.

Is there an app for torque specs?

With the help of diagnostic scanner hardware, the Torque Lite and Torque Pro apps for Android give you a peek into the inner workings of your car’s brain.

How is bolt torque determined?

DETERMINING TORQUE The general equation for bolt load based on applied torque is T = KFiDb where K = torque coefficient. K is a function of the coefficients of friction and collar friction in the joint, and these are based on variables such as surface finish, coatings, and so on.

Does Haynes manual have torque specs?

When it is necessary to specify a torque value for a particular fastener, Haynes will provide it in either foot-pounds (ft-lbs.) or inch-pounds (in-lbs.). One foot-pound of torque is equivalent to 12 inch-pounds of torque. Torque values below approximately 15 ft-lbs.

What is the torque spec for lug nuts?

80 to 90 ft-lbs
And when you look at that, and realize that the average torque required on a lug nut, to hold the wheel on, is 80 to 90 ft-lbs, well you can imagine how over-tightened some of these lug nuts are.

Are torque specs really important?

Applying exactly the right amount of torque is important to ensure proper clamping between the engine block and the tensioners or idler pulleys, for instance. And the consequences of applying too much or too little torque can be dire, as we’ll discuss below. …

Do Haynes manuals have Torque specs?

Is Torque Pro app free?

Torque is a cutting-edge vehicle diagnostic and performance scanner app for your Android smartphone. Torque Lite is the free version of Torque Pro.

How do you check the correct bolt torque?

Bolt torque can be checked with a tool such as a torque wrench, but without a value as a guideline, a torque wrench offers no advantage. To arrive at the correct torque value, several other values must be found first. Two principles influence the correct clamping pressure for each bolt, known as clamp load. The first is bolt diameter.

Do all retaining bolts have the same torque spec?

The individual retaining bolts will more than likely have at least one torque spec, but maybe even multiple or different ones per bolt. Example, a water pump that bolts to a timing cover will have long and short bolts. The long bolts that go into the engine block will have a different torque values then the short ones that thread into the cover.

Should I care about torque specs?

Bottom line is this: If you care, you’ll be fine. Torque specs are quite sloppy on anything except Rocket Surgury and head bolts, and the latter comes with great instructions and often bespoke thread lubricant.

What is torque and why is it important?

Proper torqueing is vital to the function of the bolt and is determined by several, often conflicting factors. A properly tightened bolt has its material stretched slightly, but not beyond its elastic limit. The bolt material, most commonly steel, resists this natural stretching and creates a clamping force upon the assembled substrates.