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425hp Engine Top-End Build

Mighty Mouse, Part 3 of 5

383 Stroker Engine buildPart 1 of our ultimate engine-building guide talked to the prep work, and part 2 spoke to the lower (rotating assembly) build of the block. In this installment, we’ll build the top-end of our engine, which will include the heads, push rods, rocker arms, intake manifold, fuel injection system and more.

For our engine’s top end, we chose Holley’s aluminum, pre-assembled 2.02” heads, which are perfectly designed for maximum flow, efficiency and power / torque output. We also chose Lunati roller rockers, and Lunati pushrods. GMPP provided their serpentine accessory drive system, we ordered a K&N cone air filter (part # RC-5004) and Holley topped off this engine build with their billet distributor and a Holley Stealth Ram multi-point fuel injection system (more on that later). This combination of top-end components provides the perfect level of engine efficiency, torque and power output, as well as reliability. And, you’ll see how it all comes together.

 Chevy small block 383 stroker

Engine Highlights: 

  • GM Performance Parts 383 Stroker Block, 1-piece rear main seal, 4-bolt main – part # 88962516
  • GM Performance Parts Serpentine Accessory Drive System w/out A/C – part # 12497697
  • Lunati fully balanced rotating assembly
  • Lunati “SledghammerSledgehammer” Forged steel stroker crank
  • Lunati “Voodoo” cam, roller rockers, push rods, double-roller timing chain and lifter set
  • Holley Stealth Ram multi-port fuel injection system – Part #: 91603211
  • Holley aluminum 2.02 heads – Part #: 300-552-1
  • Holley billet aluminum high-performance distributor
  • Pro-Tru aluminum flat-top pistons
  • High Performance engine bearings
  • MSD Ignition 8.5 mm super-conductor plug wires


Holley Aluminum Heads Installation

Chevy Small Block Stroker Engine BuildWith your engines lower assembly completed, you can now begin the final and most satisfying portions of an engine build – the top end. This is where it really comes together. For this install guide, we’ll be using a set of pre-assembled Holley 202 aluminum heads. If you are building your own heads, you will need further instruction and specialized tools to complete this. For your average engine builder, pre-assembled heads can’t be beat and as you will see below, they are a piece of cake to install.
Check stroker motor buildInstalling Holley Aluminum headsStart your top-end engine build by rotating the engine on the stand slightly, so that one cylinder deck is horizontal. Place the head gasket on the engine and carefully set the head onto the deck.
Chevy 484 Stroker buildHolley aluminum heads on Chevy small block engineThere is a special sequence to tighten and torque heads onto an engine. I have always used a permanent marker and identified each head-bolt hole on the heads with the torque sequence (see picture on the left). This makes torqueing the bolts that much easier later. Any engine manual will have this torque sequence available. Repeat this process and install the other head. That’s it, the heads are installed.


Push Rods and Rocker Arms Installation

Next it is time to install the pushrods and rocker arms on the engine. The pushrods are a piece of cake. Simply look down the hole of the pushrod to make sure it is clear (this is where the oil flows up from the lifters, to lubricate the rocker arms and valve springs). Coat the ends of each pushrod with assembly lube, but do not pack too much of it into the oiling hole. Then slide a pushrod into each hole of the head and seat it into the piston cup of each lifter. Do this on one side of the engine only as you will need to rotate the engine on the stand to work on it later – you don’t want pushrods falling out. This part went by so quickly and easily, that we forgot to snap photos.
Chevy small block 383 stroker build using holley and lunati componentsWe used Lunati aluminum roller rockers for their efficiency and durability. Prior to installing the roller rockers, clean them with denatured alcohol and air dry. Then coat them lightly with engine oil. Add a bit of assembly lube to the rocker arm pushrod seats. NOTE: The installation of rocker arms varies by manufacturer and is significantly different between standard stamped-steel rockers and roller rockers (we use the latter for this project).
Chevy small block 383 stroker build using holley and lunati componentsSlide the rocker arms onto the rocker studs on one side of the engine. Pay special attention to the positioning and make sure they are seated in the lifter and rocker arm seats fully. Install the polylocks loosely onto the rocker arm studs with the set screws backed off. Do NOT tighten until you complete the lifter adjustment. Repeat this process for the other side of the engine.  
To adjust the INTAKE valves, we recommend you work with one cylinder at a time. Turn the engine over by hand in the direction of its running rotation until the exhaust pushrod just begins to move upward to open the valve. Stop rotation. The intake lifter is now on the base circle of the cam and the intake valve is ready to be adjusted. 

Hydraulic Lifter Cams: Tighten the polylock until all the slack is taken out of the rocker arm and pushrod.  By lightly turning the pushrod with your fingers as you tighten the polylock, you will discover or feel a point at which there will be slight resistance.  At this point, you have taken all the excess slack out of the pushrod.  You are now at zero lash.  Turn the polylock one-half turn more, and while holding it with a wrench tighten the set screw using a T-handle or allen wrench.  This will give you the ideal pre-load of the rocker arm, pushrod, and lifter. Repeat this procedure for each cylinder and carefully adjust all intake valves. NOTE: Solid Lifter Cams have a different method by which to adjust the valves. Consult your manual for this process.

Chevy small block 383 stroker build using holley and lunati componentsTo adjust EXHAUST valves, turn the engine over by hand until the intake pushrod moves all the way up.  Rotate past maximum lift, approximately one-half to two-thirds of the way back down.  The lifter is now on the base circle and the exhaust valve can be adjusted.

Hydraulic Lifter Cams: Rotate the exhaust pushrod with your fingers and begin to tighten the exhaust polylock.  When you feel the resistance on the pushrod, you are at zero lash.  Rotate the polylock one-half turn more and then tighten the set screw. Go through the exhaust valves and repeat the procedure carefully.  Now all of the valves are adjusted with the proper pre-load. NOTE: Solid Lifter Cams have a different method by which to adjust the valves. Consult your manual for this process.

Once all of your valves are adjusted, you can pour engine oil onto the rocker arms, springs and pushrods, paying particular attention to the rollers and pushrods. This will assist with the initial engine fire-up lubrication.

Since you will need to install the intake manifold and fuel delivery system (among other things), I tend to leave the valve covers off until later, but that is my personal preference.


Intake Manifold and Fuel Injection System Installation

Chevy small block 383 stroker build using holley and lunati componentsFor our engine, we chose the Holley Stealth Ram multi-point fuel injection system. This fuel injection system not only looks amazing (the red-anodized throttle body inlet valves look spectacular), but its tunnel ram design helps to build more power. The plenum and runner designs promote excellent mid–range torque along with outstanding high RPM power – perfect for our 383 stroker engine. The Stealth Ram comes available in a polished or matte finish (we chose the latter). It also comes with all of the software needed to fine-tune your fuel injection system to your specific engine. The Stealth Ram kit comes replete with;

  • Upper and Lower intake manifolds
  • 58mm Billet Throttle Body inlet 
  • Clear Anodized Fuel Rails
  • Fuel Injectors
  • Fuel Pressure Regulator
  • 255 L/hr fuel pump and fuel filters
  • Commander 950™ ECU computer
  • All wiring harnesses
  • Software and communications cable
  • All Sensors
  • Detailed installation and tuning manuals
Start by prepping the engine block by cleaning the surface where the intake manifold bolts to it. Pack the intake valley with rags or tape it off, and then using sandpaper, scuff the engine block surface to prepare it for gasket sealer.
Next, remove the rags and place the intake manifold gaskets onto the heads, and throw away the rubber gaskets that mount on the front and back of the engine – they never work and always leak (trust me). Place a bit of gasket sealer above and below the tips of the intake manifold gaskets, and then run a 1/2” to 3/4” bead of high-temp gasket sealer along the front and back of the engine where the manifold bolts to it. Be liberal… it’s easier to clean up the excess gasket sealer, than to strip your engine down again later due to a vaccum leak.
Chevy small block 383 stroker build using holley and lunati componentsChevy small block 383 stroker build using holley and lunati componentsCarefully place the intake manifold onto the engine and heads, ensuring that it is aligned before it comes into contact with the gasket sealer. Once it is aligned properly, drop the intake manifold bolts into the holes. You will likely need a combination of wrenches, sockets, u-joints and crows feet to get to all of the bolts – this is not uncommon for a small block Chevy intake manifold. Snug all of the bolts finger tight, then following the appropriate torque sequence, tightening all bolts.

You can now install the fuel injectors, fuel rails, intake plenum, throttle body and fuel-injection wiring harness according to the instructions.

Chevy small block 383 stroker build using holley and lunati componentsWith the fuel delivery system completely installed, you should prime the engine using a heavy-duty electric drill and a priming shaft (you can rent one at your local auto parts store). Prime the engine for approximately 15-20 minutes, or until you have oil flowing through each of the pushrods for 2-4 minutes straight. This will ensure that the entire engine’s rotating assembly is fully lubricated. NOTE: If your engine is going to sit for several days before you start it, you should re-prime and pre-lube the engine again before starting.
Before installing the valve covers on your engine, double-check your polylocks and all of the intake manifold and head bolts for proper torque settings.
To top off your top-end engine build, you can now install all of your engine accessories such as brackets, alternator, power steering pump, etc. For our build, we installed a GM Performance Parts (GMPP) serpentine accessory drive system which allows us to run a convenient serpentine belt. We also upgraded our power steering pump to a Performance Steering Components (PSC) high output pump. PSC makes some of the finest steering components in the world.
Chevy small block 383 stroker build using holley and lunati components  Chevy small block 383 stroker build using holley and lunati components  Chevy small block 383 stroker build using holley and lunati components  Chevy small block 383 stroker build using holley and lunati components  Chevy small block 383 stroker build using holley and lunati components 
Chevy small block 383 stroker build using holley and lunati componentsChevy small block 383 stroker build using holley and lunati components Your engine is now completely assembled. Step back, admire your handiwork and celebrate with a cold drink or two of your choosing. As you can see, it was not all that difficult to accomplish, given a good book, some good tools, the right parts and a bit of patience.
GM Performance Parts
Web: www.gmperformanceparts.com


Holley Performance Products Inc.
1801 Russellville Rd.
Bowling Green, KY 42101
Phone: 270 782-2900
Fax: 270 781-9940
Phone (Tech): 270 781-9741
Web: www.holley.com
11126 Willow Ridge Drive
Olive Branch, MS 38654
Phone: 662-892-1500
Fax: 662-890-6309
Wiseco Performance Products
7201 Industrial Park Blvd.
Mentor, OH 44060-5396
Phone: 1-800-321-1364
Fax: 440-951-6606
Web: www.wiseco.com
ATK Engines
1102 West North Carrier Parkway
Grand Prairie, TX 75050
Phone: 866-721-2315
Email: salesdesk@high-performance-engines.com
Web: www.high-performance-engines.com
The Horsepower House
251 New Porter Pike Rd
Bowling Green, KY
Phone: 270-792-2399?
Steve Schmidt Racing Engines
8560 E. 30th Street
Indianapolis, IN 46219
Toll Free: 1-800-957-7223
Phone: 317-890-7178
Fax: 317-890-1829
Web: www.steveschmidtracing.com 
PSC Motorsports
11468 S FM 730
Azle, TX 76020
Phone: 817.270.0102
Web: www.pscmotorsports.com




About Rick Webster

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