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If you've followed along from the beginning, you already know about our sinister plans to install our subject 383 V-8 into the heart of the "SuperBurb" project rig. (For those of you new to these pages, please refer to www.fourwheeler.com for a little background on the project.) Our goal here is to turn upwards of 6,500 rpm and produce right around 500 rear-wheel horsepower. To do this, we started with a GM Performance Sportsman block. To provide air and fuel to this beast, we needed a pair of high-flowing heads. After much discussion with builders, hot rodders, and pro-racers, we narrowed our search down to just a handful of manufacturers. Eventually the racer-oriented industry mainstay Trick Flow was our favored choice for a pair of high-performance 195cc aluminum heads. Trick Flow is a leading producer of race-quality top-end kits and individual engine componentry. In this segment, we're going to showcase the heads and some tricks for making them work better, as well as addressing the cam and fuel-injection system we plan to use to feed the mill. Read on and check out the latest round of goods Stover picked for the buildup and why. While we decided to go with the a'la carte method on our stroker buildup, there is a much easier way to source parts for a balanced engine. Trick Flow offers complete top-end kits that take the guesswork out of the whole process. Each kit comes with heads, a camshaft, a timing set, rockers arms, springs, pushrods, gaskets, seals, fasteners, and more. The best part of these kits is that all the components are matched and ready to run, saving you time and money. Check out www.trickflow.com to learn more.  These Super 23 Street/Strip...  These Super 23 Street/Strip 195cc aluminum heads from Trick Flow (PN 30400015-CNC) are priced similarly to cast-iron heads but you get better performance and less weight thanks to their aluminum construction. We like the fact that Trick Flow dyno-tests them to prove they make more power than similarly priced competitors' heads. Designed to be a direct fit, these heads will accept most factory accessories and are available in three separate combustion-chamber profiles: 62-, 64- or 72cc. We opted for the 72cc version to help us reach our target goal of 500 rear-wheel horsepower. They come fully assembled with valves, valve springs, locks, retainers, rocker arm studs, and guide plates. Some versions even come with a 50-state emissions-legal E.O. number. However, because our Suburban is a '72, we don't have to worry about emissions testing in California. (Be sure to check your own state's emissions regs.)  Here you can see the CNC-profiled...  Here you can see the CNC-profiled combustion chamber of our new heads. They feature angled spark-plug holes to help keep plug wires away from header tubes, and stainless-steel valves and hardened exhaust valve seats for use with pump gas.  These 2.02-inch stainless...  These 2.02-inch stainless steel intake valves are crucial to the performance of these heads. A large intake valve like this will allow more fuel and air into the combustion chamber, which is especially important for a naturally aspirated engine where air delivery so directly governs performance.  Another thing we like about...  Another thing we like about the Trick Flow Super 23 Street/Strip heads is their 195cc intake ports shown here. Thanks to a high-velocity, small cross-section design, these heads will actually promote low-rpm torque without sacrificing higher-rpm horsepower. This should give us a very broad powerband, which is always a good thing for a heavy vehicle like our Suburban.  Our Trick Flow heads came...  Our Trick Flow heads came partially assembled with dual valve springs. While we like this arrangement, we decided to change it for fear that we might get into valve bounce at higher rpm. "Valve bounce" is an adverse condition where the valve does not stay seated, due to the combined effects of the valve's own inertia and spring resonance during the valve closure phase. Valve bounce can effectively reduce the closing force, allowing valves to reopen partially, which is highly undesirable. Trick Flow claims the springs supplied with our heads would handle upwards of 6,500 rpm. However, we plan to spin our engine to 7,000 rpm on occasion when we hit the nitrous in mud and sand, so to ensure our valvetrain would survive the abuse, we swapped in a set of lightweight Beehive springs from Comp Cams (PN 26986-16). If you consider how fast a valve spring and its retainer move at high rpm, you can appreciate why shaving off an ounce here or there can really affect things. This shot shows the two different types of valve springs, side by side. Notice the smaller dimension of the top portion of the Comp Cams spring on the left. This tapered or "Beehive" design allows for less spring mass and it uses smaller and lighter-weight retainers. The end result is less weight. We weighed each arrangement and found the Beehive design to weigh 50.6 grams less than the traditional Trick Flow dual-style springs. A lighter-weight valvetrain will allow the engine to rev up more quickly, giving it that snappy off-idle throttle response everybody likes.  This photo illustrates the...  This photo illustrates the difference between the two different types of spring-retainer locks that came with each valve-spring setup. Notice the gold color locks in front; these are for the Comp Cams Beehive spring retainers. While the Beehive locks do actually weigh more than the Trick Flow units, if you take into consideration the smaller spring retainers these locks are paired with on the Comp Cams units, you actually shave off 14.7 grams per spring.  Here you can see the two different...  Here you can see the two different types of springs installed on our heads. Notice the way the Beehive spring-retainer locks fit tightly together while the Trick Flow locks have a small gap between the two lock halves; this more precision fit is yet another instance where we felt confident about our choice to upgrade to the Comp Cams setup. The total valvetrain weight savings we netted by going with the Beehive spring setup is 1,048 grams-that's almost 21/2 pounds. The blue roller rocker arms you see in the photo came from Summit Racing (PN SUM-G6937-16). These are nice lightweight, narrow-body roller rockers CNC-machined from high-strength extruded aluminum. They feature a 1.5:1 ratio and also have needle-bearing fulcrums and hardened roller tips to maintain smooth, long-lasting operation.  To feed Stover's Stroker,...  To feed Stover's Stroker, we went with the Edelbrock Pro-Tuner EFI system (PN 3690). We picked this particular setup because of its real-time tunability and simplicity of adjustability. It didn't hurt that the system is capable of supporting up to 1,000 hp, either. Designed to be installed and programmed by the average shade-tree mechanic, this system features Windows-based software, a rugged waterproof control unit, an OEM-quality wire harness, an MSD Pro Billet Distributor, adjustable rev limiters, a fan control, data recording, wide or narrow band O2 inputs, a "check engine" light circuit, and a lot more.  This is the induction manifold...  This is the induction manifold we requested for our stroker motor (PN 29783). Edelbrock offers these units with either a Victor or Super Victor Series EFI manifold and an included fuel-rail kit. Designed to work seamlessly with the Pro-Tuner EFI system, this intake setup should allow for a simple configuration when it comes time to fire up the engine.  To pressurize our Pro-Tuner...  To pressurize our Pro-Tuner EFI system, we secured the recommended fuel pump and regulator kit (PN 35943), also from Edelbrock. Matched for our application, this high-quality fuel pump and regulator should provide a smooth, consistent fuel pressure, which is key to the performance of any EFI system. These kits are compatible with all grades of gasoline or methanol, and the regulators feature 1/8-inch NPT gauge ports. We like the fact that the pump is an external-type design, allowing for easy troubleshooting if we should ever experience issues on the trail.  This cast-aluminum ECU cover...  This cast-aluminum ECU cover (PN 3613) will help protect the ECU from engine heat, plus it adds a trick look to the otherwise plain-jane computer.  The MSD Pro Billet HEI distributor...  The MSD Pro Billet HEI distributor that comes with the Edelbrock Pro-Tuner EFI system features durable Weather Pack connectors and a billet-aluminum body. The really cool thing about this distributor is the Cam Sync function that makes it super-easy to set up with EFI systems. This setup features a built-in LED that illuminates when the sync signal is detected, assuring you that the distributor is in sync with the cam timing. This distributor also features ball-bearing guides for stable operation through higher rpm.  When it comes to engine building,...  When it comes to engine building, the camshaft is the equivalent to the central nervous system of the human body. The manner in which any engine runs is governed by the size and shape of the lobes on the camshaft. We ordered a hydraulic roller camshaft from Competition Cams (PN 12-000-8) with a very specific grind profile to suit our needs for our desired power and intended use. We needed a cam capable of producing good power through a driveable rpm range. To do this, we contacted the Comp Cams Help Hotline (800/999-0853), a free telephone service that allows engine builders and consumers to discuss various details of engine components with a certified professional. After about 10 minutes on the phone with the friendly folks at Cam Help, we had a grind selected to work with our stroker buildup. The information that sets one cam apart from another can seem like rocket science to the untrained, which is why Comp Cams offers this free service.  These hydraulic roller lifters...  These hydraulic roller lifters from Comp Cams (PN 853-16) are designed as a retrofit for early-model blocks equipped with a standard hydraulic cam. Once installed, they allow use of a hydraulic roller camshaft. Due to the design of our Sportsman block and the fact that we wanted to run a hydraulic roller cam, these style lifters were our only option. Unfortunately, they are not cheap, but we feel the performance gains associated with a hydraulic roller cam will make the investment well worth it in the end.  We fell in love with this...  We fell in love with this three-piece billet-aluminum timing cover (PN 5424) from Comp Cams because it has more useful features than a supermodel. We have to warn you this little unit is a bit on the pricey side, but when you consider what you get for the money, it's pretty cool. The cover features a built-in cam button with thrust adjustments and a removable inspection plate that when detached reveals chain pretensioners to help prevent chain slack, which aids in maintaining super accurate timing. This part also allows easy access to the cam and crankshafts without having to drop the oil pan.
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