There are many important tools you'll need before beginning to assemble your first LS1. You already have the majority of these, and they are so generic they don't merit a mention here (various metric wrenches, a feeler gauge, and so on). We'll start with some of the more important, purpose-neutral tools you might already have, then go on to tools needed for engine builds. Finally, we'll conclude with tools that are specific to LS1 builds.
All prices quoted are from the manufacturer if sold direct; otherwise, they are from Summit Racing. While you won't see all of these tools used in this month's issue, we'll get to the ones we miss next time.
OK, so you probably already have one or two torque wrenches lying around. Basically, torque measures the force needed to turn a fastener, and while this force is not the same as knowing how securely the fastener is actually clamping the part(s) the fastener is screwed into, there's normally a strong correlation between the two. Thus, the reliance on torque figures for many bolts in an engine.
Physics of the situation aside, the problem is that these suckers don't last forever: over time, their internals stretch and accuracy is lost. The result is in an under- or over-tightened fastener. So you'll need to buy at least a couple of new ones: one for torquing normal-size fasteners (around 100 lb-ft is the max you'll need for an engine build) and another for tightening smaller fasteners (with accuracy in the inch-pound range).
Torque Angle Gauge
General Motors specifies "torque-plus-angle" fastening procedures for some of the major bolts used to hold an LS1 engine together. For example, the rod bolts are torqued to 15 lb-ft plus 75 degrees; cylinder head and main cap bolts are tightened in a similar manner. This method is designed to prevent the false readings that torque wrenches can sometimes give; for example, if the fastener's threads have been improperly lubed, or a metal burr contacts the underside of the bolt's washer and adds resistance to turning.
In order to perform this procedure, a so-called torque angle gauge is necessary. This one from Snap-On retails for $67.85. However, this little item will not be necessary for each and every LS1 build. The reason is while GM uses this method to torque many of its engine fasteners, many aftermarket manufacturers do not. As you'll see in the feature story, ARP uses a simple torque spec on its main and cylinder head bolts and studs, and Lunati uses fastener stretch figures on its rod bolts. We suggest not dropping the coin on this baby until you have all engine parts picked out and know the fastener tightening method the manufacturers specify.
A caliper is a tool used to accurately measure inside and outside dimensions as well as depth dimensions. You'll need it during the engine build as there are lots of measurements to take and verify during engine assembly, and accuracy and precision are a must.
This 6-inch Powerhouse caliper is known as a "dial" caliper because of its use of a dial readout, which indicates measurements down to the nearest thousandth of an inch. So-called "digital" calipers also are available and have a digital readout in lieu of this unit's mechanical dial; however, they are significantly more expensive. The Stainless Steel Dial Caliper shown carries PN POW151205 and includes a protective case. It can be had for $44.95.
Dial Bore Gauge
Dial bore gauges allow you to measure very precisely the inside diameters of medium-sized to large-sized cylindrical holes. For our purposes, these include cylinder walls as well as main bearing bores. The tool is unlike other measuring tools in our arsenal as it can measure these things away from the edge of the hole; it's designed to reach deep down the cylinder to take measurements anywhere from bottom to top.
Ours is a PN POW205025 unit from Powerhouse ($99), capable of measuring diameters in the range of 2 to 6 inches. It's accurate down to a half a thousandth, which is fine for the type of engine-machinist-checking we'll be doing. A more accurate version is available that will measure down to the nearest ten thousandth of an inch, but it'll cost you three times what this baby does (and it's unnecessary unless you're doing your own machine work).
Piston Ring Filing Tool
The vast majority of piston rings available on the market are a file-fit design, and so you'll need a piston ring filing tool to safely and properly fit them to your cylinders. Pictured is Powerhouse's PN POW105050. This device clamps to a table and allows piston rings to be filed quickly thanks to its coarse-grit carbide wheel. It's designed so that the ring can be held squarely onto the tool, preventing crooked ring ends (just one of the reasons a standard file can't be used).
Fancy-dancy electric versions are available that even take off a specified number of thousandths at a time before automatically turning off. But would you rather spend several hundred cabronies, or just $65 like we did? Besides, this unit does the same job; it'll just take a little more time and patience to use.
Piston Ring Squaring Tool
This item goes hand-in-hand with the piston ring filing tool. Used during the piston ring file-fitting process, its purpose is to properly set the piston ring in the cylinder during end gap measurement. If the ring isn't perfectly perpendicular to the cylinder walls, inaccurate gap measurements will be the result.
This particular unit works for cylinder bores between 3.810 inches and 3.990 inches. Retailing for just $24, it's available from Powerhouse under PN POW105001.
Connecting Rod Vise
Aftermarket connecting rods come shipped pre-assembled with their bolts tight--very tight. To get them apart, a special type of vise is necessary. This is because a standard bench vice's hard steel will damage the surface of a connecting rod. Though invisible to the eye, this damage results in a stress riser and can cause the rod to break into pieces.
This Powerhouse Sportsman Connecting Rod Vise retails for $89.95 and carries PN POW351185. It simply clamps into any standard bench vise--and, with its red anodized finish, looks pretty cool too.
Piston Ring Compressor
Other styles of piston ring compressors are available, but the easiest and safest to use is the fixed-size, tapered-style ring compressor. This device sits on top of the cylinder bore and allows the piston to be slipped safely into the bore with the rings already installed and clocked. Our unit is a PN POW103875 from Powerhouse ($28) and works for pistons up to 3.905-inch diameter.
Many sizes of these are available, and you'll want to purchase the one with the next larger size compared to your actual piston diameter. (In our case, 3.905 is just larger than our piston size of 3.903 inches.)
Rod Bolt Stretch Gauge
As mentioned earlier, many aftermarket connecting rod manufacturers give a bolt stretch specification for their rod bolts rather than a torque figure. That's because the most accurate method of determining the clamping load of any fastener is to know how far it has elongated; since the shape of a connecting rod allows one access to both ends of the rod bolts, why not be as accurate as possible and measure the stretch?
For our rod bolt stretch gauge, we again turned to Powerhouse. The company sells this PN POW101300 unit for $119.95. It's accurate to the nearest thousandth of an inch and is adjustable to accommodate bolts up to 2.75 inches in length. Less expensive alternatives are available but they're bulkier and hence more difficult to work with.
Pushrod Length Checker
A different set of heads, rocker arms, or even a different thickness head gasket will require a change in pushrod length. This is particularly true with the stock LS1's non-adjustable rocker design, but even a swap to aftermarket adjustable rockers will require different-from-stock-length pushrods if the change is severe enough.
Crane sells this PN 99725-2 Adjustable Checking Pushrods kit. This particular kit works for a pushrod range of 6.125 to 7.50 inches (the stock pushrod length for an LS1 is 7.400 inches), but longer length checkers are also available. Two pushrods are included, one for the intake and one for the exhaust. The adjustable feature of these pushrods allows you to put them in an assembled (but not running!) engine and adjust their length until the proper valvetrain geometry is obtained. You can find this tool for $34.88.
In order to properly install a camshaft, a degree wheel is a must-have item. By attaching to the front of the crankshaft, a degree wheel indicates crankshaft rotational position. This allows the camshaft to be properly "phased in" with the crank, ensuring that valve opening and closing events happen at just the right time in each cylinder.
Powerhouse's PN POW101500 9-inch Degree Wheel will do the job just fine--and at $16, it's a steal. Though other special tools are needed to properly degree the camshaft and are included in so-called "degree wheel kits," you'll see in the second part of our feature story how we improvised with other tools we already had--and hence were able to save some cash.
LS1 Cylinder Head Bolt Thread Cleaning Tool
At the factory, GM uses a substantial amount of thread compound on the LS1's cylinder head bolts. This is good because the head bolts stay put while the engine is running, but it becomes an issue when trying to rebuild one of these engines. The leftover residue clogs the threads in the block and won't allow new cylinder head bolts or studs to install properly.
Enter ARP's PN 912-0011 LS1 Clean Out Tap. This tap is the correct size and length to properly clean all 20 of the M11 cylinder head bolt holes used on the LS1 engine, allowing head bolts to reach the proper torque and head studs to thread in easily. Price: $51.34.
LS1 Front and Rear Cover Alignment Tools
On the LS1 engine, the oil pan is a stressed member and adds to block rigidity. For this reason, it can't simply be slapped in place; along with the front and rear engine covers, it must be carefully aligned with the block.
This is one area in which you may unfortunately need to invest some cash in buying some of GM's own specialty "J" tools. Made by SPX Kent-Moore for use by GM, a J 41480 could be had for around $115, while a J 41476 would set you back about $400. Since they are designed solely for the purpose of installing the LS1 front and rear covers and oil pan, you'll likely only use them once, and we'd advise borrowing them from a local GM dealership or speed shop. Since they are nearby, SLP loaned us theirs; on the right is the J 41480 Front/Rear Cover Alignment (Oil Pan Surface) tool and on the left is a J 41476 Front/Rear Cover Alignment (Crankshaft Oil Seal Area) tool.
LS1 Crankshaft Rear Oil Seal Installation Tool
In lieu of buying yet another GM "J" tool (GM J 41479), Wheel To Wheel Powertrain can hook you up with one of its own Rear Seal Install Tools. Retailing for $275.00, this item allows a new rear crank seal to be properly installed into the rear engine cover, negating the possibility of oil leaks. The two black halves are placed on either side of the cover with the new seal in between; tighten the bolt and they pop the seal into place nice and evenly. The shiny aluminum donut-shaped piece helps align the rear cover to the block, complementing the front/rear cover alignment tools mentioned earlier.
In lieu of actually buying this item (which, again, you may only use once), a better idea for the home hot-rodder is to ship both your front and rear engine covers to Wheel to Wheel, and they will install new GM seals for you. They'll do this for $139 ($219 for seals designed for dry sump oiling system engines).
LS1 Crank Turning Socket
During the assembly of any engine, it's necessary to turn the crankshaft periodically. Though this can be done by hand initially, it becomes more difficult to spin the crank later in the build when the piston rings add drag to the rotating assembly.
Powerhouse's PN POW103075 Pro Crankshaft Turning Socket is specifically designed to grip onto the unique snout of the GM Gen III V-8 crankshaft. It can be turned with any 1/2-inch drive ratchet or breaker bar and even includes a provision to attach a degree wheel via a knurled nut. Don't build an LS1 without one of these! It's yours for $44.95.