The main upgrade we chose for our ignition system is a set of MSD's Multiple Spark Coil (MSC) LS-1/LS-6 Blaster Coils. The coils are sold for $578.60 under PN 82458 and fit nearly all Gen III engines; MSD also has available a PN 82468 "MSC II" coil kit for Gen III engines that use a different factory wiring harness connector (such as GM trucks). Also pictured is a custom-fit MSD 8.5mm Super Conductor Wire Set that retails for $59.30 (PN 32823). Also available in red, this particular wire kit actually is designed for GM trucks and is a bit longer than the Camaro/Corvette wire kit; this helps make up for the extra coil-to-plug distance caused by our ETP heads' raised valve cover rail. | 
We picked up a set of ARP stainless hex bolts (PN 434-2302, $68.56) to attach the stock coil brackets to the valve covers, not realizing that MSD actually includes new plated bolts with its coil kit (see the sidebar for more detailed info on this kit; the provided bolts are high-quality but not quite as good as stainless). GM wants threadlock on the coil-bracket-to-valve-cover bolts, so we oblige; the bolts-five per cover-are torqued to 106 in-lb. | 
The coils then bolt atop the brackets. To get them to work, some light grinding to the bracket is required, as these coils are slightly larger than the OEM units (thanks to the beefier electronics inside). Also, you'll need to use washers under the coils (some more than others) to space them off the bracket a touch, or else they'll contact the valve cover bolts and other raised parts of the valve cover. Fortunately, we had extras thanks to our duplicate set of bolts from MSD. |
We then connect the factory coil wiring harness to each coil. It's a bit of a stretch, but it'll reach with some slight adjustments. While currently capped off with an MSD-supplied plug end, a close look will reveal an extra wiring connection in each coil; it's for an upcoming MSD ignition controller. This controller will reportedly feature automatic nitrous timing retard and other goodies LS1 enthusiasts have been sorely lacking for some time. Look for a test of this item in an upcoming issue! | 
With the coils in place, we install new NGK spark plugs (since this is a new head, they'll get 15 lb-ft of torque) and pop on our MSD wires, being sure to use adequate dielectric grease on each end. We'll of course have to disconnect the wires from the plugs to get our headers to go on, but you can see here how these wires are more than long enough to reach the plugs. The plug end of each boot is also bendable to just about any angle, which helps orient the wire to clear all exhaust header primaries and other obstructions-a very nice feature. | 
We were a little confused when we discovered that ARP's engine mount bolt kit includes only six bolts, while each engine mount requires four. Never fear; two of the GM bolts need to be reused on the driver side as they have studs sticking off the top to hold a heat shield. After torquing all eight engine mount bolts to 37 lb-ft, install and torque the stock heat shield nuts to 89 in-lb. |
SLP sells this PN 100221 Harmonic Balancer/ Underdrive Pulley kit for 1998-2002 LS1 F-bodies ($236.85). It meets SFI spec 18.1 and as such is engraved with a unique serial number. SLP's 25 percent underdrive design frees up horses while also maintaining proper cooling system operation and alternator voltage. GM demands that a new bolt always be used in the front of the crank (as this bolt is apparently torque-to-yield), and SLP includes one. Not included are new, shorter serpentine belts; our belts ran about $55 at the local (rather high-priced) auto parts store. | 
SLP says to follow the GM service manual directions and use a J 41665 Crankshaft Balancer and Sprocket Installer tool, but we borrowed a proven-to-work system that includes a longer crank bolt (M16 x 2.0 x 120mm versus the stock 103mm length) and some washers. You can buy a longer bolt like this from a well-stocked local hardware store or an industrial supplier like McMaster-Carr. Also pictured is our LS1's old crank bolt to use in the installation. But the longer bolt is key: if you try to install the balancer using just the old crank bolt, you'll strip the first few threads out of the crank snout. | 
Position the balancer on the end of the crank, then insert and turn the longer crank bolt to slowly push the balancer onto the snout. Don't lube the crankshaft front oil seal, it is designed to be dry at startup. But you'll probably want to lubricate the underside of the head of the bolt and any washers you have under it (the washers facilitate bolt turning and also prevent the bolt from prematurely bottoming out). Do not lube the threads of the bolt, however. Once the longer bolt bottoms out, insert an OLD crank bolt and tighten until you hit-get this-240 lb-ft. If you can't get it that tight (this would likely take a torque wrench designed for a dump truck), at least make sure you meet SLP's depth spec. |
After removing the old crank bolt and ensuring that the crank snout is recessed about 2 1/2-4 1/2mm into the bore in the balancer, the final step is to install the NEW SLP-provided GM crank bolt. Torque to 37 lb-ft, then put on a breaker bar with a torque angle gauge like this one from Snap-On (not properly zero'd here, you'll note). The bolt must be turned an additional 140 degrees. If you don't have a torque angle gauge, just draw some lines with a magic marker and watch them as you turn (140 degrees is about 3/8 of a turn). Though you will need to apply some real force to get the bolt to turn far enough, don't worry about stripping the threads in the crank snout-so long as most of the threads are engaged, they're not going anywhere! | 
The stock water pump is reinstalled using new GM gaskets (PN 12559271, $4.84) and new, stainless steel ARP (PN 434-3201, $36.25) bolts torqued to 22 lb-ft. You can also see we've put in the stock coolant air bleed pipe here, which runs between the front portions of the two cylinder heads (with rubber hose that will eventually run to a port on the radiator attached). New air bleed pipe gaskets from GM are a good idea too (PN 12551933). Some earlier LS1 engines had a four-point pipe that also ran to the back of the heads, but it can't be used with most aftermarket intake manifolds as they are generally thicker and sit lower; owners of these cars will have to convert to the two-point pipe with GM blockoff covers in the rear. | 
An SLP 160-degree thermostat was chosen for this build in the interest of gaining the efficiency and power benefits that come along with lower engine running temperatures. Carrying PN 100223, it fits all 1997-2003 LS1 engines and retails for $56.60. The thermostat is installed onto our GM water pump and its ARP bolts (included in PN 434-3201) torqued to 89 in-lb. |
Now's a good time to mention an item that could potentially save a whole lot of headache. Though many cooling systems will seal properly when water/antifreeze is poured into the system, once in a while a leak occurs-most often in the head gasket area. This sometimes even happens before the car is run, with water pouring into the cylinders or onto the garage floor as coolant is dumped into the radiator. At less than $5 a pack, these GM Cooling System Seal Tabs can be had at your local dealership under PN 12378254 and will help ensure all coolant-related gaskets in the engine seal properly. Drop them into the radiator, and they'll circulate helpful particles the first time the engine is run. | 
After removing the masking tape from the intake ports, clean the cylinder head surface thoroughly and look into the ports one last time to make sure no foreign material is in there. Although the LS1 intake manifold uses durable rubber port seals instead of old-style gaskets, they still need a clean surface in order to seal properly. You can see the wiring harness for the knock sensors in the foreground; this is your last chance to install this item before it's hidden beneath the intake manifold! | 
The F.A.S.T. 90mm top shell (PN 30-54005, $549.95) is drilled and tapped for our nitrous nozzles and assembled to our existing F.A.S.T. inner and lower shells. The manifold is set in place using the existing rubber port seals, but keep an eye on them while you set the intake down as they may want to creep out on you. The stock intake bolts are installed with some threadlocker and torqued in sequence to 44 in-lb and a final pass of 89 in-lb. You'll note that we've already reinstalled our nitrous and fuel lines running to the nozzles. If you're putting a direct port nitrous system on your new stroker motor, now is the time-you'll recall that installing one under the tight cowl of an F-body is quite a task! |