Recomendations for Torque Wrench WTB

[CARRERIC]

Hey guys,

Any recommendations on a good torque wrench to buy for my 911? From torqueing down lugnuts to working on engine. What is more useful on overall car 1/2" or 3/8".

Thanks

[Rot 911]

Here's what Warren (Early S Man) had to say on this topic: "If you are serious about doing your own work on brakes, suspension, and engine, you will eventually need both 3/8" and 1/2" drive torque wrenches. Which one you need now depends on what part of the car you need to work on first! For 13 mm and smaller fasteners, you will need a 3/8" drive, 5-75 lb-ft range torque wrench, and using a 10-150 lb-ft wrench at the lower end of its' measurement range on the 7-18 lb-ft requirements for 10 mm to 13 mm nuts (and the M8 and M10 Allen bolts used on CV-joints) or bolts would be a BIG MISTAKE!

If lug nuts (94 lb-ft) are what you need to tighten first on the agenda, then you need a 1/2" drive torque wrench first. But, please don't be tempted to tighten the 10 mm nuts on the sump drain plate with it! Stripped out studs are the most likely result at your next oil change are a likely result ... if you do!"

Need I say more?

[makaio]

I broke down and purchased a Snap-On 1/2 drive clicker style about 6 months ago. It's a 50-250 ft lbs. (I think). about $225 from the truck. I love it. Hopefully the last one I'll ever buy in that size.

If you are just going to buy one, i would go 1/2" drive.

[J P Stein]

Took my 1/2 drive back to Sears this last Sunday cause it was broke (clicker type). It's a couple of years old and had led a hard life doing 914 rear axle nuts.
The guy says they have only a 90 day warranty. I says "great, so now it's a breaker bar"
No more 1/2 drive clickers for me.

[jpachard]

I purchased a Snap on 1/2 drive one on flea-bay for 150.00. It was perfect. I had the calibration checked on one of the trucks.

Cheers, James

[pbs911]

I have the Sears 3/8 drive for the lower torque values (4about $95). I picked up a cheepo ($29) Harbor Freight 1/2 drive for the higher torque values and lug nuts. No complaints on either.

[Sarah]

We just got a Craftsman 1/2" drive.

(You see...at my recent DE training I pretty much had every wrong tool imaginable...but very helpful & knowledgeable porsche club people have been helping us compile the correct tools for our 930...thank goodness).

[Wayne 962]

Here's a quote from my new book:

Tools - Without a doubt, the most useful tools in your assembly arsenal are a pair of good-quality torque wrenches. A precise, accurate torque wrench is absolutely essential to proper assembly. For the 911 engine, you will need to tighten bolts ranging from 8 N-m (5.9 ft-lbs) to more than 170 N-m (125 ft-lbs) on some models. I don’t personally know of any torque wrench capable of accurately spanning this range, so you will have to purchase two of them. I recommend purchasing one from a company like Snap-On that can accurately torque from 15 to 135 N-m (11-99 ft-lbs), and another one that is accurate from at least 45 to about 265 N-m (33-195 ft-lbs) or so. I also own a small torque wrench that can accurately measure from 0-14 N-m (0-10) ft-lbs. This is useful for nuts that don’t require too much torque. Over-tightening a fastener can sometimes be worse than under-tightening it.

There are three basic types of torque wrenches The beam style wrench uses a long rod of metal that bends to apply the torque. This wrench rarely goes out of calibration because there are no moving parts, and the material properties of the beam don’t change. You can expect these torque wrenches to stay accurate within 2-5% over their lifetime. The dial gauge torque wrench has a small dial mounted on the handle, and indicates the amount of torque applied on the gauge. These are quite accurate over time, although they should be periodically calibrated.

The most popular torque wrench is the click-style one. This is the wrench where you set the torque value, and then you turn the fastener until the wrench clicks. It’s important to stop at the point when you apply the click so that you don’t over-tighten the fastener. In addition, these torque wrenches have a tendency to become significantly uncalibrated over time. This affects all click-style torque wrenches, regardless of manufacturer or quality. If you do decide to use this type of torque wrench for your rebuild, I recommend that you have it calibrated prior to assembly. Failing to properly torque an important fastener like one of the rod bolts can result in catastrophic engine failure. In this case, an inch-ounce of prevention is well worth the foot-pound of cure.



It’s very important that your nuts and bolts get tightened to their proper torque. There is a right way and a wrong way to torque a fastener up to its final value. The correct method is to use what is known as running torque. Basically, as you begin to tighten the fastener, you keep moving it in a steady constant motion until you hear the torque wrench click. Do not stop moving the wrench until you hear this click. If you do stop, or run out of working room, then loosen the nut and retighten again (except in the case of rod nuts/bolts and flywheel bolts).

Using a running torque method will give you the most accurate torque values on your fasteners. The wrong way of tightening fasteners is to use short strokes, stopping and starting until you reach final torque. This can lead to torque values that are less than the required specification. This is because static friction helps to keep the nut from moving. If you place a torque wrench on a nut, tighten it, and it does not move, then you cannot be assured that it tightened to the value that the wrench is set to.
With small nuts and bolts, holding proper torque is very important, and you can damage fasteners and studs if you over tighten them too much. When you are finished using your torque wrench at the end of the day, make sure that you ‘wind’ it down so that it’s at its lowest setting. This will help to keep the internal springs inside the torque wrench from deforming, and will assure that it keeps its accuracy over time. Always use the torque wrench to tighten everything, and never use an impact wrench during the assembly procedure.

-----------------------------------------

I have three torque wrenches - a 1/2 drive, a 3/8 drive and a small 3/8 drive (0-20 ft-lbs). Kurt V is absolutely right - don't use a torque wrench in the outer reaches of its range - get ones so that you can use their 'sweet-spot.' And make sure that they are calibrated regularly. We used to have them recalibrated about every 6 months at Hughes Space and Comm.

[Noel]

Now for the really cheap alternative. I've been using a Autozone special Click type torque wrench as my DE event wrench for about 3 seasons now and have good luck. The wrench was only ~$20 so, I would have to go through 10+ wrenches to get into the Snap-on price range. Interestingly, I test it by setting it for 98FtLbs and have the guys at the track safetly tech verfy 98FtLbs during safetly tech.

Normally I do not hesitate to pay for quality but, I've had good luck so far and I pretty much only use it for Lugnuts so 1 lb accuracy is not an issue for me.


Noel

[GIBSON]

I was curious about 1/2 inch torque wreches so I asked some good friends who run tire and wheel store what they use. They said that after trying many different types they ended up with a Snap-On torsion-bar type wrench. It's accurate, stays in calibration longer, is easy to use and very sturdy. Also, there's no spring to worry about, in case you forget and leave the wrench somewhere other than the zero setting. I've seen them on eBay lots of times, seem to go for around 150 or so. They are ideal for wheel torque.

[ChrisBennet]

I use a cheap Sear/Craftsman 1/2"250lb clicker type for most things, a nice 1/2" 150lb clicker type, and a precision (2% accuracy) 3/8" size beam type for doing rod bolts, head nuts and other critical fasteners.
I believe that the most people (including myself) don't torque large fasteners to the "book" value. Errors caused by the torque wrench, socket extensions, lube or lack of lube, and nut to washer friction (rusty or clean) all conspire to yield pretty imprecise torque values. The fact that nuts aren't falling off cars left and right indicates to me that there is a certain tolerance built into the book values so I'm not going to lose any sleep over it.

When you purchase Raceware fasteners they send along some very interesting info on torque wrenches:

IMPORTANT INFORMATION CONCERNING TORQUE WRENCHES AND TIGHTENING TORQUES
The purpose of a torque wrench is to allow you to PROPERLY tension a fastener.
There are three basic styles of torque wrenches, the beam, the dial and
"clicker" The beam style has been with us for many years and has a pointer
than moves along a scale as you apply force to the wrench handle. The dial
torque wrench works on the principle of hydraulics and has a gauge that
indicates the force applied. The "clicker" style torque wrench is perhaps
the most common torque wrench in use today because of its convenience and
mass marketing. The "clicker" style uses a spring as a reference to
determine a given force. When used properly all three styles of torque
wrenches can be effective.

The BEAM STYLE torque wrench rarely goes "out of calibration" because it
has no moving parts, or only one if you consider the pointer. Unless the
beam style
wrench is subjected to abuse, it's accuracy stays pretty consistent over
it's lifespan, which is probably forever. These wrenches are generally
available with accuracy ratings of 5% or possibly 2%. This is acceptable for
most applications.

The DIAL style gauge as more moving parts and the potential for easy
damage if not carefully handled and maintained. All gauges have variations
in accuracy over their operating range. Good quality dial style torque
wrenches can be very accurate, but should periodically be checked for
calibration. This should be accomplished by a reputable, skilled instrument
shop NOT by comparison to another torque wrench, which could also be out of
calibration.

"CLICKER" style torque wrenches were originally intended for use where the
ability to read a gauge or scale was physically impossible. Unfortunately
some wise marketer decided that the "clicker" style wrench would be ideal
for those who do not know how to use a wrench properly..and now EVERYBODY
it seems owns one of these devices. We would STRONGLY recommend that you
carefully read what we have to say about ALL "clicker" style torque
wrenches before using it to install any important threaded fastener. Brand
and model have NO effect on the accuracy of a "clicker" wrench.

"Clicker" style wrenches use a spring, (and additional mechanisms) to
create force for the wrench to match when you apply force to the handle.
When you exceed the setting torque, the wrench clicks indicating you have
reached or exceeded the force required. This technique creates a lot of
potential for error. Fist, you are using a spring to set the force and all
springs change their rate over time and use. Second, once you exceed the
balancing force, and the wrench clicks, you can still apply an unknown
additional force.

We have seen "clicker" style torque wrenches that were out of calibration
as much as 50%. That is NOT a misprint, we said 50%. These wrenches were top
quality wrenches that were NOT subjected to abuse. Some had been calibrated
within a years time, by competent labs. We strongly suggest that if you
choose to use a "clicker" style torque wrench, WHICH WE DO NOT RECOMMEND,
that you have it calibrated REGULARLY, and ALWAYS BEFORE INSTALLING
IMPORTANT FASTENERS.
The use of socket drive extensions is NOT recommended because they cause
errors in torque readings.

-Chris

[ChrisBennet]

Raceware also includes some interesting info on fastener friction:

In quality threaded fasteners as much as 80% of the torque applied to
tighten them is used to overcome the friction in the threads. Only about 20%
of the force is used to actually tension the fastener. That means that any
change ins the FRICTION has DRAMATIC effect on tension. All quality
fasteners have specific installation instructions that dictate what
lubricant if any should be used when tightening the fastener. Lubricants
such as motor oil, anti-seize, moly lube, cam lube, STP(tm), ect, ALL have
different friction characteristics.

USING THE WRONG LUBRICANT CAN CHANGE THE THREAD FRICTION BY AS MUCH AS
30%, CAUSING A FASTENER TO BE IMPROPERLY TENSIONED.

-Chris

[Planter91C2]

many of us, including myself, use th $9.99 1/2 inch clicker torque wrench from harborfreight with no problems

[slakjaw]

i like my 1/2 inch one from the Cornwell guy

[Doug E]

Count me as another Harbour Freight user. I bought both the 1/2" and 3/8" models.

[mike f]

Another Harbor Freight fan here. I must say that I do not plan on rebuilding my engine. If I did, I'd probably spring for a Snap-on. I mean, if you are about to spend that much time and $$$ on a rebuild, why skimp on the wrench? For now, though, I'll put the $200 difference into other toys.