2004 GMC Sierra Buildup - LSX376 Engine

We like to be the custom truck guinea pig for you. Whether it be making mistakes during an install, getting so close to finishing a project only to need extra parts, or even buying the wrong parts when we thought they would work, we like to help you know the ins and outs of an install before you crack open the toolbox. When it came time to drop in the GM Performance Parts LSX376 engine into our Project Novakane '04 GMC Sierra, we quickly learned that swapping a high-performance engine where a factory 4.8L once resided wasn't as easy as just bolting it in place.

Ideally, you pull the 275hp engine out, bolt in the 750-plus-hp engine and begin the recreation of Eleanor's last stand in "Gone in 60 Seconds." However, once real life kicks in and you're elbow deep under the hood, you realize that an engine capable of 750 hp needs high-performance parts, and you also learn that there are differences between an LS-based Vortec V-8 that was designed more than 10 years ago and a newer LS3 engine that is one of GM's best ever small-blocks. Here in this story you'll learn what we learned, but without wasting all of the extra money like we had to do. A valuable resource we found when tracking down our engine parts was Summit Racing. Known for go-fast, hot-rod parts, Summit also carries a full line of OE parts that you would typically find at a parts' store. Rather than drive to the store, only to find out the part was out of stock or a special order item, we stayed home and ordered them from summitracing.com. If you're considering pulling your worn-out LS-engine out of your '99-and-newer Chevy or GMC and swapping a high-performance crate engine, here are some important parts to secure before you turn a single wrench.

An engine that is making more than 550 hp needs constant fuel, and a great deal of it. With our truck having 145,000-plus-miles on it, a fuel pump upgrade was a good idea anyway, but to find a suitable candidate that would support 750-plus hp, we contacted Lonnie's Performance Auto, out of Perryopolis, Pennsylvania. Lonnie's specializes in performance fuel systems and his dual in-tank units can support up to 1,000 hp. In 2004, GM changed the fuel system to a non-return system, which means Lonnie had to be a little creative when designing our system, but thanks to a Corvette-style filter and adjustable fuel pressure regulator from Aeromotive, our fuel system is darn-near bulletproof.
An engine that is making more than 550 hp needs constant fuel, and a great deal of it. Wit
With the fuel concern handled, we switched our focus to the air getting into the cylinder heads. Last month, we showed you the incredible MagnaCharger 2300TVS system that will easily turn our LSX376 into a rowdy mouse motor, but the throttle-body flange for that supercharger was designed for the '07-and-newer throttle bodies and is not compatible with our '04 unit. To remedy this dilemma and upgrade our factory 75mm throttle body, we ordered a 90mm LS7 throttle body for an '09 Corvette Z06 (part number 12605109) that bolts right to the supercharger inlet. However, the car throttle bodies have a different wiring harness connection and the truck wiring will not plug into the throttle body. Thankfully for those of us who feel the need for speed, Torque Rush Performance, in East St. Paul, MB, Canada, has created the X-Link. Making a throttle body upgrade an easy plug-and-play install, the X-link is an interface module that plugs directly to the throttle body and then to your factory truck wiring harness.
With the fuel concern handled, we switched our focus to the air getting into the cylinder
Massive amounts of air and fuel going into the engine is vital, but keeping the engine happy at higher boost levels was a big concern. Creating a win-win for our GM Performance Parts crate engine, Snow Performance makes a Stage 2 water methanol injection kit for GM trucks with Mass Airflow Sensors (MAF). By picking up the voltage signal from the MAF, the Stage 2 kit can quickly and accurately deliver the water methanol mixture, which instantly cools the air intake temps and raises the fuel octane to race gas levels. The Stage 2 kit also includes a digital variable controller that increases pump output based on input voltage. What this means for the engine is that high boost levels are achieved safely and without fear of harming the internals. Even if you're truck isn't going to receive a supercharger, the Snow Performance water methanol kit can add serious horsepower easily, safely, and without breaking the bank.
Massive amounts of air and fuel going into the engine is vital, but keeping the engine hap

To ensure every bit of the supercharger's boost gets into our engine, we need to be sure there is zero supercharger belt slippage. Superchargers need constant traction to provide constant boost. Rather than use an old cog style, we're going to add strength and performance by switching to an eight-rib serpentine pulley setup. ATI Racing is well-known in the racing community for high-performance harmonic dampers, but they also manufacture a complete line of performance pulleys. We had the complete eight-rib conversion in just a few days. Overdriven LS-engine crank pulleys/dampers are also available from ATI Racing and will increase the amount of boost made by the supercharger.
To ensure every bit of the supercharger's boost gets into our engine, we need to be sure t
OK, so we tackled fuel and air going into the combustion chamber, now we need to get all of that air out of the engine. To help our LSX376 breathe easy, we ordered a pair of American Racing Headers long-tube headers. These bad boys are made out of 304 stainless steel, feature 3/8-inch flanges and massive 17/8-inch primaries complete with hand-ported inlets. The primaries merge into a large 3-inch Y-pipe collector and will be connected to our Banks 3-inch Monster exhaust system. Another bonus, these headers are made right here in the U.S.A., and will fit lowered trucks, so our Project Novakane won't be having any clearance issues.
OK, so we tackled fuel and air going into the combustion chamber, now we need to get all o
With more air going in and more fuel meeting the air, a really big bang happens. That big bang means the creation of heat. Heat robs power, can wear down your engine prematurely, and can quickly melt surrounding parts. To keep the LSX376 running nice and cool, we upgraded the puny factory radiator with a handbuilt, aluminum, Direct-Fit unit from Be Cool. Engineered to mount in place of the factory radiator, the Be Cool radiator has better cooling power, is up to 40 percent lighter, and guaranteed to lower your coolant temperature a minimum of 20 degrees. Now that is impressive. Combine the Be Cool aluminum radiator with Be Cool's own coolant and antifreeze, and there is no doubt our project truck will running nice and cool. A cooler engine means more power.
With more air going in and more fuel meeting the air, a really big bang happens. That big

You wouldn't put old bearings in an engine you're rebuilding, so why would you reuse old sensors for your fuel injection on a new crate engine? That's the same thought we had when it came time to the details. Details such as a new temp sensor, O2 sensors, cam and crank position sensors and even a new Mass Airflow Sensor (MAF). You probably think of Summit Racing for go-fast parts, and rightfully so, but you may be pleasantly surprised to learn that Summit also carries a full line of replacement parts for your truck.
You wouldn't put old bearings in an engine you're rebuilding, so why would you reuse old s
Truck maintenance and crate engine swaps don't usually go together, but with the tired engine out, it provided a perfect opportunity for us to replace many of the parts that would typically be tossed when performing annual maintenance. While we were checking out all of the new sensors at Summit Racing, we went ahead and pulled the trigger on parts that didn't make sense to install on a new engine. Those parts included new upper and lower radiator hoses, a new oil pan gasket, and even new motor mounts. Not pictured, we also placed an order for a remanufactured water pump and new, 180-degree thermostat. As a helpful tip, we recommend looking over your existing engine and deciding on what parts you are going to replace. Make a list and a budget, then determine what parts are an absolute must and start with those.
Truck maintenance and crate engine swaps don't usually go together, but with the tired eng
Engines are held together by dozens of bolts- small ones, big ones, and bolts that need to be torqued to a specific pound feet. On an LS engine, all of those bolts are metric and many were designed to be torqued once and then replaced. What that means for those of us building an LS-based engine, investing in new, quality bolts is a must. The undisputed leader in engine and accessory bolts is ARP. Engineered for racing applications, each bolt is stronger than a typical grade 8 fastener and thankfully, they recently released a complete bolt kit for LS engines. Complete in the kit, you get new oil pan, intake, valve cover, thermostat, timing cover, rear motor cover, exhaust manifold, water pump, valley cover, motor mount, and ignition coil bolts. That's an impressive kit and we also took the opportunity to buy new rod and head bolts while were at it. We opted for the optional 12-point head and each bolt is black, for a stealth and racecar appearance.
Engines are held together by dozens of bolts- small ones, big ones, and bolts that need to

This is a shot of the LSX376 with the MagnaCharger 2300TVS set on top. By combining these two parts with the upgrades and OE replacement parts in this story, our engine will be roasting the tires for years to come. We didn't order them in time for this story, but we also upgraded our alternator and starter with high-output and high-torque units from Powermaster. As a side note, we did learn several important things when we did the swap. The LS3 has a crank sensor in the front, whereas our 4.8L had it in the back. We just extended the wires to make it work and so far, so good. Also, the LS3 has the knock sensors on the bottom of the block, but the 4.8L had them in the intake/oil valley. Again, we extended and rerouted the wires to trick the computer into thinking everything was normal. You gotta love hot-rodding! Making horsepower isn't cheap (as out wallets can attest), but we made the decision to spend more now and have peace of mind, rather than spend less and have an engine failure down the road.
This is a shot of the LSX376 with the MagnaCharger 2300TVS set on top. By combining these

Parts Used:
Aeromotive injected fuel pressure regulator AEI-13101 $149.95
American Racing Headers long tube headers GMTE78NC $1,375.00
ARP Bolts LS-engine 12-point black bolt kit ARP-534-9705 $263.99
ATI Racing Super Damper and 8-rib pulley set ATI-917339 $952.85
Be Cool direct-fit aluminum radiator BCI-61102 $947.95
Lonnies Performance dual in-tank pump kit $675.00
Powermaster XS torque starter PWM-9509 $235.95
Summit Racing camshaft position sensor SMP-LX756 $34.95
Summit Racing crankshaft position sensor SMP-PC273 $49.95
Summit Racing MAF tuned for cold air SUM-29007B-C $294.95
Summit Racing motor mounts AXT-2909 $54.95 (2)
Summit Racing oil pan gasket SUM-G2334 $39.95
Summit Racing oxygen sensor BCH-15733 $68.95 (2)
Summit Racing throttle position sensor ACF-213-912 $39.95
Summit Racing coolant temp sensor SMP-TX89 $19.95
Summit Racing water pump AAZ-58-626 $73.95
Summit Racing upper radiator hose GTR-62262 $28.99
Summit Racing lower radiator hose GTR-62261 $16.39

Total: $5,447.52
(Does not include tax or shipping)

SOURCE
Aeromotive 7805 Barton Street Lenexa KS 66214 913-647-7300 www.aeromotiveinc.com	Torque Rush Performance 204-232-3118 www.torquerush.com
American Racing Headers 22 Elm Place Amityville NY 11701 631-608-1986 www.americanracingheaders.com	Powermaster 1833 Downs Drive West Chicago IL 60185 630-957-4019 www.powermasterperformance.com
GM Performance Parts P.O. Box 33170 Detroit MI 48232 800-577-6888 www.gmperformanceparts.com	Be Cool 310 Woodside Avenue Essexville MI 48732 800-691-2667 www.becool.com
ARP 1863 Eastman Avenue Ventura CA 93003 800-826-3045 www.arp-bolts.com	Lonnies Performance Automotive 659 Central School Road Perryopolis PA 15473 724-322-8505 www.lonniesperformance.com
Summit Racing 800-230-3030 http://www.summitracing.com	Snow Performance 1017-A East Highway 24 Woodland Park CO 80863 866-365-2762 www.snowperformance.net
ATI Performance Products 6747 Whitestone Road Baltimore MD 21207 877-298-5039 www.atiracing.com	MagnaCharger 1990 Knoll Drive Ventura CA 93003 805-642-8833 www.magnacharger.com