Project Trans Am – 22 Months Later

I’m now 22 months into my 1981 Pontiac Trans Am and it feels like I’ve got nothing done! But this blog post is a good outline of everything that has been happening since November, 2011.

Short Block Assembled

The hiccup with the wrong piston valve relief was sorted with the machine shop relatively quickly. After getting the short block assembled in December, I went over my notes and decided to research one of the other concerns I had during assembly. I found that I did do something wrong with the ARP wave-loc connecting rod bolts. In a pinch I called Don at DCI Motorsports and he helped me out big time! He fixed my problem without putting a dent in my wallet. He’s a real Pontiac expert and DCI Motorsports will be getting all of my Pontiac business for now on! As far as what I did wrong, I’m rather embarrassed so don’t ask! All anyone needs to know is it was my fault and it’s fixed now. Oh and I’m never ever going to build another engine with ARP Wave-loc bolts, too much hassle to deal with in a stock engine build.

The short-block is done and the cam and timing chain is installed and degreed! The remaining engine parts will be assembled within a week before I plan on starting the motor. Waiting till the last minute will allow me to inspect the internals one last time. The remaining assembly should not take too long either.

New Years Eve Engine Break-in!

On New years eve morning I went over Joel’s to help him with his engine break-in. Talk about the best new year eve ever, I got to hear a freshly re-built Pontiac start for the first time! Joel planned on doing the break-in the night before, but with all the stuff going on that night with the kids I wasn’t able to come out. Luckily he didn’t get everything setup till late that night so he delayed the break-in till morning. Between monitoring for leaks and checking for other problems, it’s a good idea to have at least one buddy around during the break-in process. It’s definitely exciting, not as exciting as child birth but its definitely a car’s equivalent!

Here’s a pic of Joel’s 400:

My 400 once assembled will looks very similar to this.

Front Chassis Ready

It took a lot of time, but I got the front sub-frame painted! I used Eastwood Rust Encapsulator as a primer and Eastwood Extreme Chassis Satin Black as the top coat. I applied it with roller and sponge brushes. It turned out great! All rust spots I ground down with the angle grinder, all other spots were roughed up with 320 grit paper, cleaned with Simple Green and then dried with paint thinner before painting.

Once the front suspension is back on the car my plan is to wheel the car out and apply Eastwood Underframe Coating to the inside of the chassis. I now think I should have done that first.

Front Suspension

The front suspension is ready for re-assembly! In December my buddy Joel helped me remove the A-arms, spindles safely from the chassis. The process rquires compressing the coil springs. Joel also had a set of chains to use as an extra level of safety in case the spring got loose. Once the arms were removed, they were sand blasted then I gave them a light coat of Rust Encapsulator. Then my friend Tim pressed out the old bushings and pressed-in new ones. I went with stock OEM rubber bushings. The ball-joints were also replaced and new lower ball joints were pressed in. Thanks Tim! If you live in the Delaware Ohio area with a classic car and need a mechanic, please contact me, I’ll give you Tim’s contact info. He knows his muscle cars!

I also cleaned and painted the spindles and brake shields with Eastwood Brake Gray. The shields were a pain in the butt, I first had to find a replacement for the drivers side since it was mangled for what ever reason. Then in the process of grinding off rust on the replacement I damaged it. I ended up buying a pair off eBay. Honestly I should have just bought the pair off eBay in the first place, the time I spent cleaning the rusty one I found wasn’t worth the time or effort when it was all said and done. Lesson learned, some stuff you restore, some stuff is easier to replace.

As far as the suspension is concerned, it is primarily stock. I went with 590 Moog springs, which are correct springs for a 1981 Turbo Trans am, but cut 1/2 coil off to compensate for the lighter engine (Pontiac 400 without AC). The 1/2 coil should help lower the front end slightly so it has a more hot-rod look. I also got Edelbrock ISA shocks for the front and rear. The anti-sway bar will remain stock, which is already a hefty 1-1/4″ thick, but I did upgrade the bushings on the links to polyurethane. All other bushings are rubber.

Steering Column

I just started working on this. I already purchased a new turn signal mechanism because the left turn signal will not engage. After taking apart the steering column I have discovered that there’s nothing wrong with the steering column turn signal mechanism, the problem is with the pivot pin that holds the turn signal lever. So now I am in the process of finding out how I can fix this, at the moment I am not finding anyone who sells a replacement “pivot pin” for 1981 Firebird. I am going to take the steering column apart completely to tighten the tilt mechanism and re-grease the bearings. I will also be painting the column black while it is apart.

What’s Next

The plan now is to start re-assembling everything! First is the front suspension, then I can paint the inside of the front frame. Once the weather breaks, I can start installing sound deadening and insulation along the firewall, followed by re-installing the heater box, dashboard, steering column and other firewall items. Once that’s all done, I can start thinking about getting the engine together and installed!

Automotive Sound Deadeners, Insulation and Anti-Rattle Products

There are a lot of sound deadening, insulating and anti-rattle products for automotive applications. The list below (as of February, 2012) is the most comprehensive list of products organized by type.

Spray on Sound Deadened/Insulation

Spray on sound Deadeners and insulation are paint-on products that can be applied in a number of ways. LizardSkin is the most popular product of this type.

  • Boom Mat (spray-on) – rattle can based spray-on insulation
  • CoolCar– paint-on ceramic based insulation
  • eDead (v3) -paint-on latex polymer
  • eDead (v5) -paint-on ceramic microsphere polymer
  • LizardSkin – paint-on ceramic based insulation
  • NoiseKiller – paint-on insulation
  • QuietCar – paint-on viscoelastic polymer based insulation

For similar products, search Google for: High temp epoxy mastic

Paint-on solutions are, for the most part, permanent solutions. If you ever think you may want to remove the product in the future, research the product you want to use to find out how the product can be removed.

Though not covered in this article, undercoatings and rust proofing products that are applied to the outside of the vehicle can also provide levels of insulation and sound deadening.

Roll based cut to fit Sound Deadened/Insulation

The most popular form of insulation, roll based cut to fit sound deadeners and insulation come in rolls and are typically cut with utility knives or scissors. Application can either be glued in place, peal-n-stick like scotch tape, or heated with a heat gun. Dynamat is the most popular product of this type. SecondSkin has the most dynamic array of options depending on how far you want to go in your sound deadening/insulation project.

  • Audio Technix – butyl (possibly asphalt) rubber based insulation with 1 side of aluminum
  • Boom Mat (Damping Material) – butyl rubber based insulation with 1 side of aluminum
  • B-Quiet Ultimate (Brown Bread) – butyl rubber based insulation with 1 side of aluminum
  • CSI Heat Shield – fiber tech padding based insulation with 2 sides of aluminum
  • Dynamat (Dynamat Xtreme) – butyl rubber based insulation with 1 side of aluminum
  • eDead (Butyl Mat) – butyl rubber based insulation with 1 side of aluminum
  • eDead (TekLite) – closed cell neoprene based insulation
  • EZ Cool Insulation – closed cell neoprene based insulation with 2 sides of aluminum
  • FatMat – asphalt based insulation with 1 side of aluminum
  • Hushmat Silencer Megabond – butyl rubber based insulation with 1 side of aluminum
  • Hushmat ULTRA – visco-elastic polymer (butyl rubber) based insulation with 1 side of aluminum
  • MegaMat – FatMat or FatMat Mega Mat, asphalt based insulation with 1 side of aluminum
  • Milla Mat – FatMat, asphalt based insulation with 1 side of aluminum
  • RAAMmat (RamMat) – butyl rubber based insulation with 1 side of aluminum
  • Second Skin (Damp Pro) – butyl rubber based insulation with 1 side of aluminum
  • Second Skin (Luxury Liner) – mass loaded vinyl based insulation
  • Second Skin (Luxury Liner Pro) – mass loaded vinyl with layer closed cell neoprene
  • Second Skin (Heat Wave) – natural fiber (better than jute) based insulation with 1 side of aluminum
  • Second Skin (Overkill) – closed cell neoprene based insulation with 1 side of aluminum
  • Thermo-Tec Cool-It Mat 146xx series – butyl rubber based insulation with 1 side aluminum
  • Thermozite – environment friendly (post consumer recycled plastic bottles) based insulation with 1 or 2 sides of aluminum
  • ZillaMat –  asphalt based insulation with 1 side of aluminum (possibly re-branded FatMat)

Butyl based insulation is the most popular cut to fit insulation. It has ideal properties to deaden sound. Depending on the quality of the butyl used, it can give off a rubber smell (should go away over time) and can be difficult to remove as the butyl may eventually melt onto the surfaces of the vehicle.

Asphalt based insinuator is a mixture of the material used for roofing and possibly butyl rubber. It has ideal properties to deaden sound. The smell of this type of material can be an issue in excessive heat conditions (avoid installing in high-heat areas such as firewalls or on panels next to exhaust systems). Like butyl based insulation, can be difficult to remove if it melts onto the surfaces of the vehicle.

Closed cell neoprene based insulation is ideal for weight saving applications, can withstand higher temperatures and is resistant to mold and mildew. This material is not as good as butyl at hushing deep sounds but it does insulate and prevents vibrations well.

Mass loaded vinyl based insulation is ideal as a top layer over your insulation. Its application would be the equivalent of achieving luxury vehicle sound deadening. It is typically applied in conjunction with other products such as butyl and/or closed cell neoprene.

Fiber (jute) based insulation is ideal for factory applications. It can absorb moisture over time and should be avoided if mildew or moisture is a concern. Jute is typically packaged with pre-cut carpet and adds a soft padded feel to carpet.

Custom fiber based insulation are typically high temperature resistant and may be the only option for specific high heat applications such as under hoods and firewalls.

Note: Project Trans Am will be using a combination of EZ Cool closed cell neoprene and Thermo-Tec 146xx butyl insulation.

Recommended tools for installing insulation

  • Scissors and/or utility knives
  • Soap, water, paint thinner – for cleaning surfaces before application
  • Carpenters square, straight edge, or other straight edge tools – for cutting straight lines from insulation rolls
  • Aluminum face tape – for attaching cut seams of aluminum facing insulation
  • Butyl face tape – for wrapping around parts that may rattle otherwise, such as hard plastic wire looms
  • Velcro strips – can be cut for specific applications for preventing rattles
  • Fleece tape – wrapping around wires for preventing rattles
  • Rollers – For pressing-in adhesive backed insulation
  • Heat Gun – for heating to shape and/or gluing butyl backed insulation
  • 3M General Trim Adhesive (08088) – for gluing non-adhesive backed insulation to metal or plastic vinyl panels

Pre-cut Sound Deadened/Insulation

Typically this type of sound deadened/insulation is model specific. Most automotive retailers carry SoftSeal, Original Parts Group and/or OER brands.

  • OER – pre-cut  jute and pre-cut carpet with jute backing
  • Original Parts Group – factory replacement padding and insulation.
  • QuietRide – Dynamat brand pre-cut solutions for specific vehicles.
  • SoffSeal – high temperature hood insulation

Note: Project Trans Am will be using pre-cut carpet with jute backing.

What the Factory Did

Most all automotive manufacturers use foam, cotton, fiber (jute) and/or vinyl insulation with butyl applied only in special locations or certain situations. Butyl in particular is usually used outside of the vehicle. A good example is butyl in 3/8″ thick rope form for insulating seams around firewall bolt-on items such as heater/AC ductwork. Auto manufacturers tend to use better insulation materials in high-end luxury vehicles. No manufacturer uses butyl backed aluminum sheets of insulation in any large scale.

Other Sound Deadening and Insulation Resources

Flare Wrenches for working on Hot Rods and Resto-mods

A flare wrench is like an open end wrench with 5-6 contact sides and/or 4-5 contact corners. As it’s name implies, the wrench is intended for use on flared fittings. A normal open end wrench makes contact on only two sides, making the flare wrench ideal for better contact in certain situations.  In many cases they can be used for the same applications, though both wrenches have specific uses. There are also flare wrenches for 12 point nuts, though rare.

Most mechanics refer to flare wrenches as special purpose tools. It’s primary use is for flare based nuts attached to piping such as brake lines, fuel lines, transmission coolant lines, and other similar lines. Even mechanical based oil pressure and water temperature gauges use flare nuts for their lines, which should be installed using a flare wrench.

Not all flare wrenches are created equal. Doing research on a number of tool based forums you will find brands have a tendency to spread, meaning under heavy usage the opening of the flare wrench spreads apart beyond an acceptable amount. Another important factor is how many corners the flare wrench comes in contact with the flare nut. The S-K flare wrench in the photo above covers 5 corners of the nut, with all sides of the flare nut getting contact on the nut’s sides. This combination of edges and corners is ideal. See the diagram below to see the difference in flare wrenches.

Budget priced flare wrenches tend to use the 4 corner pattern, were-as most quality flare wrenches use the 5 corner pattern.

Depending on your budget, Allen brand (made in USA), KD (made in USA), GearWrench (made over seas), S-K (made in USA) and Williams (by Snap-on) (made in USA) brands have good reviews.

Craftsman no longer offers a raised panel flare wrench (except on their web site, most likely until stock is depleted) and has remarked their Craftsman Professional Flare Wrenches as just Craftsman Flare wrenches. The older made in USA Craftsman Professional flare wrenches were made by S-K. The new line of Craftsman flare wrenches are now made over seas.

Project Trans Am – 18 Months Later

So I’m now 18 months into my 1981 Pontiac Trans Am project and things are just now starting to come together. From April – July I really didn’t get to spend much time on the car, our new baby was coming (born June 27th) and preparing for/having him took precedence! I even had to neglect the lawn a couple weeks in July, luckily none of my neighbors complained.

Sand Blasting and Exhaust Manifolds – Blast Cabinet Blues

In August I worked on the small rusty parts for the motor. I sand blasted the exhaust manifolds before painting with Eastwood Exhaust Manifold Gray. I even purchased my own sand blasting cabinet similar to the ones sold by Summit/Jegs, but quickly discovered what a pain in the butt it is to own your own blasting cabinet. After 2 weekends using it, I decided I was better off going over to my buddy’s place rather than trying to turn my garage into a body shop. The blast cabinet I got was a table top model. Though it was technically big enough for my exhaust manifolds, it really was too small to work in, I had to open the cabinet every time I wanted to turn the manifolds to blast other sides. Perhaps if I ever had a larger garage I would get a bigger blast cabinet, but it’s just not practical for the garage I have now.

Once I got the manifolds painted, my buddy Joel baked them in his industrial oven. They came out exactly how they went in! I am pretty impressed with the Eastwood exhaust paint and will try some of their other paints in the coming months.

I also got all the other engine brackets and small parts to my core support blasted and painted.

Engine Painted and Freeze Plugs Installed – CAM PLUG ISSUES!

Painting the block and all the other parts was a labor of love. I now know why most engine builders recommend putting the engine together before painting, because it is a pain figuring out what should and should not be masked off! I figured it out though, and it sure looks good! I used Dupi-color engine paint  DE1616 Pontiac Blue Metallic. The machine shop painted the heads already with this color, so I just had to paint the block, timing cover, oil filter housing, oil pan and water pump.

I then installed the freeze and oil gallery/galley plugs. Last was the rear cam plug. This is where things went bad. The Federal-Mogul freeze plug kit I got for my Pontiac 400 came with the wrong size freeze plug. Because I had to re-install the rear oil plug a second time, I purchased a 2nd Federal-Mogul freeze plug kit, and it also came with the wrong cam freeze plug. Luckily i was looking at the cam plug in the 301 block I had (luckily I didn’t get rid of it yet) and looked at photos of other freeze plug kits and discovered the problem was with the depth of the plug. I also discovered that NAPA Auto Parts sells individual freeze plugs! So the 3rd time around I got the exact cam plug size I needed and for less than $1.50 too!

The Pontiac references I have all say the plug needs to be .03″ deep from the “lip”. The cam plug packaged by Federal-Mogul is itself just over .04″ deep, so when installed, it went in too far. With the shallow cam plug with a depth of .02″, the plug installed correctly and the cam test-fit fit without hitting it.

I learned a few things with the cam plug issue. First is I’ll never buy a Federal-Mogul freeze plug kit for a motor ever again! NAPA rocks when you’re in a pinch. Third is te importance of test fitting all the parts.  I wasn’t going to test fit the cam until I talked to my friend Tim who recommended test fitting everything and re-measuring all the tolerances of the bearings and plugs. Had I not test fitted the cam, I would have gotten much further into the build before discovering the problem, at which point would have made it a lot harder to remove and replace! Last important thing I learned is next time I’m going to buy everything from the Machine shop. I maybe saved $100 by buying everything from Summit/Jegs, but the headaches from some parts working and some not’ is not worth the savings.

Rings Filed, Rear Main Seal, Cam, Crank and Pistons Installed – ALL BUT 1 PISTON!

In September I somehow found time to file fit all my piston rings, install the rear main seal, crank, and cam! I spent one weekend just test fitting everything and using plasti-gauge to verify everything fit correctly. I actually discovered I was using the wrong main bearings in the wrong saddles during the process. Plasti-gauge is a tedious process, I never used the torque wrench so much before that weekend! IF your not familiar, you need to install the crank dry with all the bearings in and only test one bearing at a time. So if your tests go smoothly, you’re only doing this 5 total times. Unfortunately I did this 7 times because of the bearing miss-hap. After everything was said and done, all the bearings are at .002″. I also did this for all the connecting rod bearings, they are also at .002″. For the rod bearings I Was able to use a bore gauge. My bore gauge wasn’t big enough for the crank bores, so I had to use the plasti-gauge.

Rear main seal install went smoothly using a Viton rear seal. In the photo you can see it lines up perfectly, except one end came out a little bit. When the crank is installed, it presses in where it needs to be. I don’t see how this motor could leak, but time will tell!

Before I installed the crank for the final time, I installed the cam. Its a lot easier to install a cam with the crank out. Once I got the cam and crank installed, I started installing the pistons. After getting the first 2 pistons installed as pictured, I discovered that I had 5 pistons tops of one valve relief design, and 3 the other valve relief design. This stopped me in my tracks, as I should have 4 and 4 of each type. I’m now waiting for the machine shop to get the new piston top in and swap the rods. I’ve since installed the remaining pistons, so all but piston 8 are installed, torqued and ready to go.

Firewall and HVAC

In October I Decided to repaint the firewall so it would have that fresh/new look under the hood. There wasn’t any rust to worry about, and only a couple spots where there was bare metal to worry about priming, but getting all the little parts off the firewall took a lot of time. Removing the wiper motor and assembly was a monster. Once I figured out how to remove these little clips underneath the wiper arms, things started to come apart smoothly. I also removed all the seam sealer from the top of the cowl as it was pretty dried out and cracked. The seam sealer on the sides did not look bad at all, so there must be something about seam sealer being exposed to water longer that may be why it was in worse shape. Either way, scrapping and cleaning that off was a bear. Once the cowl and the firewall were clean, I did my usual prep work  (scuff with fine 3m pad and clean with paint thinner), taped off areas I didn’t want paint, and then went to work with fresh paint. I used Rustoleum Satin Black 7777. It’s not the best paint, but it’s not the worst either. Since this was going over existing paint, I wasn’t as worried about it getting damaged by drops of brake fluid someday.  The firewall turned out quite nice.

I’m also in the process of rebuilding the HVAC box. Confusing at first, Ive pretty much figured out how the entire AC/Heat system works! it’s quite interesting how much of the duct work baffles and doors require engine vacuum in order to open/close. I’m also surprised someone hasn’t figured out how to replace all this stuff with modern actuators/valves tat run on electric motors. Either way, I’m almost done rebuilding mine, just waiting on a new Actuator for switching from AC to heat (kind of important). I am installing an AC Delete panel on the firewall, but the AC option is still necessary if I want to use the vents to blow air.

Degreed Cam

My buddy Joel came over a couple weeks ago and helped me degree my Crower 60918 cam. If you’re familiar with Pontiac cams, this cam is very similar to the popular 068 cam, kind of in-between a 068 H.O. cam and a Summit 2801 cam. With the timing chain straight up the cam is at 107 degrees, really close to the recommended 108 degrees. One thing I did learn though was the importance of a good cam degree kit. I got one of those universal Summit degree kits, which worked, but a motor specific kit made by Comp Camps would have made things so much easier. Next time I degree a cam, I’m getting the Pontiac engine specific Comp Camps degree kit, as it comes with a special crank socket that the degree wheel attaches to and has the specific dial indicator attachment for connecting to a Pontiac block.

Fan shroud

The fan shroud came with a very large crack, on the top of all places. I sourced another used one that would work in the short term when I decided to research if I could repair the current one. After doing some reading I found a post that explained why glue’s typically do not work, and the best thing to do is to melt the plastic back together with a soldering iron. So with my crappy soldering iron I did just that and it worked! The stitch (if you want to call it that) looks anything but desirable though, but it works. I was thinking about running filler of some sort over it, but after spending 30 minutes sanding the plastic I decided to leave it and call it a day. I then scuffed up the rest of the fan shroud, cleaned it then threw on some Krylon Fusion plastic flat black paint. I also painted some of the intake parts and the cowl vent at the same time. It came out pretty nice!

Special Thanks!

I have to give special thanks to my friends Joel and Tim for their help this summer! With all the little complications I’ve had, I’ve almost wanted to give up and hand the motor off to a mechanic to put together for me. Their confidence and expertise helped me keep going! Thanks guys!

I also have to thank my wife for letting me spend so much time in the garage. Thanks babe!

What’s Left

If I don’t run into anymore snags and the machine shop gets me the correct piston top in the next week, I should be able to get the rest of the motor assembled, front frame painted with Eastwood’s Chassis Black and get the motor installed in the car. Hopefully by December I’ll have the cam broken into and most of the car back together!

 

Piston Ring Filer


My Pontiac 400 engine rebuild requires me to file to fit the top 2 compression rings. In order to make sure the rings keep their true edge, a mechanical Piston Ring Filer is recommended. Because I do not plan on using this tool very often, I decided to purchase an inexpensive clone from Jegs. A quality name brand (KD Tools) version of this filer is available at Amazon.com for only a couple bucks more.

The Piston Ring Filer will come with a bracket to allow you to bolt it to your workbench. Rather than bolting it to my bench, I decided to build my own platform to permanently mount the piston filer to, that way I could mount it in my bench vise when needed. I used a 1 x 6 cut about 14 inches long, with two 45 degree cuts at one end so my knuckles do not hit the wood during cranking. I then cut a 2 x 4 at 3 1/2 inches making a square block to screw to the bottom of the filer platform for pinching with my vise. The result is pictured.

 

To file a piston ring, place the ring facing up on the tongue end of the filer tool with the open ends of the ring resting within the side by side wheel bearings. With either one or both sides of the ring pressed lightly into the filing wheel, rotate the wheel counter clockwise so the wheel moves against the ring in a down and inward pattern. This will leave the top and outer edge with no rough edges. I’ve viewed one engine builder use this ring filer to file only one end of the ring, leaving the other end slightly away from the grinding stone.  Filing only one end of the ring has the advantage of allowing you to compare the filed end with the non-filed end to verify the edge is true.

You can file rings with a hand file, but you take the chance of filing the end of the ring unevenly. If you’re paranoid like me, drop the $50-70 on one of these ring filers, it’s a no-brainer.

Torque Wrenches Reviewed

I’m currently in the process of rebuilding a Pontiac 400 v8. The process has led me to buy a lot of new tools. Most of these new tools aren’t too expensive, such as a dead blow hammer and piston ring compressor. The one tool for this project that is quite an investment is a good torque wrench.

I already own Craftsman beam type torque wrenches and a Harbor Freight 1/2″ drive torque wrench. They worked well for the little things I’ve needed to torque down, but decided that they are not up to par for an engine rebuild. Thus my torque wrench research started.

Testing Torque Wrenches

Around Christmas I got an Alltrade 940759 Powerbuilt Digital Torque Adaptor. It comes with what they call a calibration cube, it’s a square chunk of metal for your vice that has a 1/2″ square hole machined into it to plug your torque adapter into. The Adaptor can be used as a torque wrench, but it is better used as a way to test the calibration of your torque wrenches. I took it over to a buddies place and we tested his torque wrenches (he had a small click-stop that measures in inches and a larger click-stop that measures in pounds, I believe both are from AutoZone). We found that placement where you held your hand on the torque wrench effected the measured torque as much as +/- 10 pounds depending on where you had your hand on the handle. Essentially we learned that you want your hand exactly where the manufacturer tells you to hold it, and you want most of the force to be applied along your index finger and thumb so the force you apply is placed exactly where the torque wrench expects it.

The following weekend I tested my torque wrenches (I have a 1/2″ 0-150 ft. lb beam style Craftsman, a 3/8″ 0-75 ft. lb beam style Craftsman, and a 20-150 ft. lb. click-stop Harbor Freight) and found them all to be very accurate. With the beam wrenches, you need to be able to read it straight on, any angle and you were reading 5-10lb over/under. The beam style wrenches have special handles that pivot exactly where you want all the force to be applied, so there was no issue of hand misplacement like the click-stop type. The click-stop from Harbor Freight however, was not as accurate counter clockwise as it was clockwise. The Harbor Freight, though accurate, was not precise and would click anywhere between +/- 3 ft. lb. when torquing tests of 75, 100 and 125 ft. lbs. This is within the advertised +/- 4%.

Precision and Accuracy

There is a difference between precision and accuracy. Accuracy is when you’re within a certain range consistently. Precision is when you hit the same measurement every time. You can be precise without being accurate, e.g. you set your torque wrench for 100 ft lb and it constantly stops at 110 ft. lbs, your precise, but it’s not accurate. To be both precise and accurate is the end goal.

What to Look For

When buying torque wrenches, there are details you need to look for.

  • Does it meet industry standards? (e.g. ASME B107.14M-1994, ISO 6789)
  • What do other folks say about the wrench
  • Type of torque wrench (beam, click-stop, split-beam, dial, digital)
  • What is the accuracy +/- in what percent of the range

The type of torque wrench is important based on how you plan on using the tool. I prefer the beam style simply because they are very reliable, you can rely on the beam to be accurate every time and they typically never need calibrated. The only down side is you need to be able to read the wrench straight on. The click-stop are the most popular, but their accuracy and precision is heavily focused on the manufacturer of the wrench. The split-beam are excellent wrenches as well that will not need calibration as often as a click-stop, but they only torque clockwise, which could be a problem depending on what you want to do. Dial type wrenches are expensive. Digital torque wrenches are great, but most are priced beyond what we can afford.

The accuracy in what percent of the range was one item that took me a while to put my head around. Basically, a torque wrench will have a range e.g. 10-100 ft. lbs, and in most of that range it is accurate. Typically the torque wrench makers call this it’s accuracy percent range.  All the wrenches I narrowed my results down to have  upper 80% range accuracy. What this means is that the first 20% of the range of the torque wrench may not be within the advertised +/- accuracy.  In the case of a 10-100 ft. lbs torque wrench, this would mean that from 10lb to 28lb the wrench may not be as effective. I suspect the lower range is not as accurate because of the low tension being applied to internal springs. With this accuracy range in mind, it may be ideal to have multiple torque wrenches to cover specific ranges.

Narrowed the Results Down

In January, I discovered there are quality wrenches under $150 if you know where to look. Here’s a quick outline.

  • CDI Torque Wrenches (Maker of the Snap-on torque wrenches) can be purchased online for a great deal less than their Snap-On counterparts. The Best thing is, they don’t hide the fact that they are a division of Snap-on. Wrenches are made in USA.
  • Precision Instruments Split Beam (maker of the Snap-on Split-Beam specific wrenches) wrenches can be purchased online for a great price as well. Split-beam are less likely to ever need calibration, but one downside is they only torque clockwise. Wrenches are made in USA.
  • GearWrench and KD Tools (divisions of Danaher Tool Group, who also make torque wrenches for Sears Craftsman) have well made torque wrenches for the money.  Torque wrenches are were made in USA.
  • Brown Line Metal Works BLD0212 Digital Torque Wrench is a new torque wrench that is the only digital wrench that fits within the budget. It is a new wrench from a new company, regardless I believe they have a pretty reliable design.  I talk further about this torque wrench at the bottom of this post. Wrench made in Malaysia.

What I Purchased

Based on all the different ranges each torque wrench advertises, I decided to purchase two wrenches.

CDI 1002MFRMH 3/8″ drive 10-100 ft. lbs: I would say this is the best designed torque wrench I’ve had in my hands to date. Changing the torque amount is easy and the wrench definitely feels like a precision tool. I plan on using this for torquing bolts between 30-100 ft. lbs.

GearWrench 85054 1/2″ drive 25-250 ft. lbs: Also well designed torque wrench, adjusting the torque setting is just as easy as the CDI model, but it doesn’t quite feel as precise as the CDI, though still in the same quality class as the CDI. The long length of the wrench makes it easier to apply torque. I plan on using this for torquing bolts between 75-250 ft. lbs.

Both the GearWrench and the CDI are both accurate and precise when I tested with my Digital Torque Adapter, both clockwise and counter clockwise. I was unable to test the GearWrench beyond 147 ft lbs due to the limitation of the Digital Torque Adapter. They are both excellent torque wrenches.

The BrownLine Digital Torque Wrench

This wrench really interests me. I tried to contact the manufacturer to see if someone sells the wrench locally and received no response. I did do some research and found the patent they filed for the wrench. I also found from an Ebay seller that the wrench is made in Malaysia.

When I reviewed the patent, I quickly figured out what they did. Essentially the BrownLine torque wrench is a beam-style wrench with a microprocessor that translates the beam measurement to digital. This essentially solves the issue with reading beam wrenches at an angle. Remember the beam style wrenches don’t go out of calibration unless the actual beam itself is broken. By reason, this wrench should last a very long time. Aside from the microprocessor, there’s not much with this wrench to go wrong. Had I been able to see one of these wrenches in person, I may have purchased one.

Conclusion

If you have the money, the Snap-on torque wrench is definitely a quality tool. If you are on a budget like me, the CDI torque wrenches (which are essentially Snap-on torque wrenches without the logo on them) are a real bargain. If you want a torque wrench you never have to worry about calibrating or torquing counter clockwise, the Precision Instruments will fit the bill nicely. If you’re on a really tight budget, The GearWrench torque wrenches are the best value priced on the market.

If you have a Brown Line digital torque wrench, please leave a comment and tell me what you think of it.

Update on July 4, 2016

My collection of torque wrenches has grown since I wrote this post.

Park Tool TW-1 Torque Wrench 1/4″ drive, 0-60 inch lbs: – I had a need to torque between 16-20 inch pounds for adjusting a Saginaw steering box. This is a beam style torque wrench which, in my opinion, is appropriate for this kind of usage. Park Tool is a tool manufacturer specifically for the bicycle industry.

CDI 2502MRMH 3/8″ drive 30 to 250 inch lbs: I purchased this for the 5-20 lb torque range. Most common usage example would be valve cover bolts.

I now am a big advocate for click-stop type torque wrenches. Both GearWrench and CDI torque wrenches provide a confident click as well as a stop that you feel when you hit the selected torque. A friend was using a generic torque wrench from Harbor Freight and had the situation where he was over torquing because he did not hear or feel the torque being reached.

If I could design a torque wrench, I would take the best of the GearWrench and CDI together. It is easier to read the numbers on the GearWrench and I prefer the GearWrench handle. I prefer the locking mechanism of the CDI and I think the click stop of the CDI is superior.