Racing Engine Build - The Ultimate Street Stock Motor
Rhyne Competition Engines Pulls Out All The Stops On This Street Stock Chevy
From the July, 2010 issue of Circle Track
By Jeff Huneycutt
Photography by Rhyne Competition Engines
Rhyne Competition Engines'...
Rhyne Competition Engines' (RCE) small-block Chevy will compete in Frank Kimmel's Street Stock racing series and produces a very healthy 454 horsepower at 5,700 rpm.
There are two schools of thought when it comes to Street Stock racing. The first is old school: use primarily stock parts to keep the costs down and the cars to a reasonable speed. Racers will have to scrounge junkyards and be inventive to make their cars both fast and durable. The second school of thought says that many of the traditional components used in Street Stock racing-particularly the small-block engine-have become too scarce in junkyards and the real world to be economically feasible, so in order to save costs stock replacement parts should be allowed.
Neither school of thought is wrong. And just like some people like ketchup on their eggs while others prefer Tabasco, they are just different.
In the case of Frank Kimmel's Street Stock Nationals touring series, the rulebook had to be purposely loose in order to draw as many cars as possible. The Street Stock Nationals is designed to give local Street Stock racers a chance to race on some pretty impressive tracks-such as Rockingham Speedway and Bristol Motor Speedway-and draws racers from all across the country. Coming from so many different tracks (and many different rulebooks), practically every car is different. In order to accommodate them, the Street Stock Nationals allows lots of different engine combinations and attempts to even things out with weight breaks and penalties.
Circle Track followed along as race engine specialist Rhyne Competition Engines screwed together a new Chevy small-block to be raced in the SSN's Polar Bear 150 at Rockingham. The engine was brand-new from fan to flywheel, and built specifically to the Street Stock National's rulebook.
We saw this as an opportunity to see the upper limit of Street Stock race engine technology. And the interesting thing about this build is how easy it is to build a race engine that stays within the spirit of Street Stock racing without wasting lots of time and money trying to refurbish old, worn out junkyard parts. The aftermarket has lots of affordable, durable components that allow the modern Street Stock racer to put together a high-power, dependable race motor without breaking the bank. We won't give the blow-by-blow of the complete engine build here since there is nothing exotic or trick going on. We're just showing you that good parts selection and intelligent engine building can produce a solid Street Stock mill. Just take a look and see.
The foundation for this build...
The foundation for this build is Dart's SHP cast-iron Chevy block. RCE's Joe Santelik, the engine builder for this project, says Dart's affordably priced SHP (for Special High Performance) line is a no-brainer. You can have a brand-new block with several improvements over stock for approximately the same cost compared to purchasing a used stock block and performing the many machining operations necessary to bring it up to spec.
One significant difference...
One significant difference from a stock block is a true priority main oiling system in the Dart SHP block that helps ensure consistent lubrication to the crankshaft main journals.
Ductile iron main bearing...
Ductile iron main bearing caps are designed with splayed four-bolt caps on the center mains, which helps this block reliably handle up to 600 horsepower.
On the opposite side of the...
On the opposite side of the block, the cylinder bores are siamesed for extra thickness. For example, the cylinder bores can be taken all the way to 4.165 and still have a minimum cylinder bore thickness of 0.230-inch.
Even with a new block, some...
Even with a new block, some machining procedures will still be necessary. Here, after mocking up the piston height, the block is decked a few thousandths to maximize compression and ensure that the deck surface is square to the crankshaft centerline.
Almost all new blocks also...
Almost all new blocks also require honing. One important touch that should be mandatory, even with a Street Stock engine build, is to hone the bores with a deck plate torqued into place. This simulates the stresses the block will see when the heads are bolted up and helps ensure you have straight cylinders in the running motor.
CNC machining that was once...
CNC machining that was once the realm of Cup engine builders has now successfully made its way to Saturday night racing. RCE uses a CNC cylinder hone that Santelik says has really improved the shop's ability to provide its customers the truest cylinder bores possible.
Of course, no matter how much...
Of course, no matter how much computer technology you have on hand, it's still important to double check every tolerance personally.
After the bob weights for...
After the bob weights for the pistons and rods are determined, the forged K1 crank is set up on the balancer.
The standard (read: cheaper)...
The standard (read: cheaper) way to balance a crankshaft is to drill holes into the ends of the counterweights to lighten them. The problem with this is the holes actually create windage and burn horsepower. Instead of drilling holes, RCE carefully cuts down the counterweights on a lathe. This is a more labor- and time-intensive process because you have to be very meticulous with your cuts, but it not only leaves a smooth counterweight, but the length of the counterweight is also shorter, reducing windage. This method of crank balancing is more expensive, but considering a crankshaft can be used for several rebuilds in these lower horsepower engines, the extra cost isn't that extreme.
Next, the crank's journals...
Next, the crank's journals are measured for consistency and to get the correct bearing clearances. By the way, this is a stroker crank that will swing the pistons 3.750-inches.
For the mains, Santelik says...
For the mains, Santelik says he likes to keep the bearing clearance between 0.0025- and 0.003-inch. This is on the tight side for a Street Stock motor, but Santelik says it provides good oil control as long as your machining tolerances are dead on.
The Clevite bearing shells...
The Clevite bearing shells are also checked with a ball micrometer to make sure they are consistent.
The cam is a solid flat-tappet...
The cam is a solid flat-tappet from Comp Cams. It is ground with 242/246 degrees of duration for the intake and exhausts at 0.050 lift, and the lobe lift is rated at 0.340 and 0.345.
RCE uses Joe Gibbs Driven...
RCE uses Joe Gibbs Driven assembly grease throughout the engine during the build. On the dyno and in the race car, the engine will run Joe Gibbs brand oil as well.
Once the cam is installed...
Once the cam is installed in the block, Santelik presses the Clevite main bearings in place and applies a light coat of assembly grease. For the main and rod bearings, Santelik mixes the Joe Gibbs grease with motor oil to thin it a bit so that the rotating assembly will spin smoothly.
The K1 rods are checked after...
The K1 rods are checked after honing to make sure the clearance, once the bearings are installed, will be between 0.002- and 0.0025-inch.
In order to minimize the chances...
In order to minimize the chances of a rod failure, the rod bolts must be checked for stretch and not simply torqued down. Stretch should be between 0.0055- and 0.007-inch. In order to make measurements as precise as possible with a bolt stretch gauge, RCE dimples the center of the rod bolts with a carbide drill bit. In this photo, the top bolt has been done while the bottom two are still unmodified.
The ring package is 1/16,...
The ring package is 1/16, 1/16, 3/16. Santelik grinds the gaps to approximately 0.020 for the first ring and 0.022 for the second. He says he would rather the gaps be too loose than too tight. A ring gap that is too loose doesn't really harm you in terms of power. But if the gap is too tight, the ends of the rings can butt together and cause serious damage to the piston and cylinder wall.
Once the rings are assembled...
Once the rings are assembled on the pistons, and the pistons on the rods, the rotating assembly is installed. Santelik double checks to make sure the top of the JE forged piston is level with the deck at TDC for the best combination of compression and squish.
The block did require a small...
The block did require a small amount of work to clear the rods with the stroker crank.
The Cometic MLS head gasket...
The Cometic MLS head gasket is laid into place. Take a moment here to make sure all the coolant holes match up. Santelic uses ARP bolts to torque the cylinder heads into place.
When you are racing with an...
When you are racing with an aggressive camshaft and stiffer-than-stock valvesprings, never go cheap with a stock-style timing chain. This double roller timing set from Comp is much more durable and can actually help provide steady dependable spark timing.
With the camshaft, rotating...
With the camshaft, rotating assembly and timing set installed, Santelik can now degree in the camshaft.
RCE uses this valley tray...
RCE uses this valley tray from Moroso because it helps keep hot oil from splashing up on the underside of the intake (heating the air/fuel charge). With the Dart block, it bolts right to the bosses in the lifter valley designed for the lifter spider in a roller-cam setup.
Santelik pointed out that...
Santelik pointed out that RCE uses this hydraulic damper installer to press the damper into place. He says that with the hydraulic unit you can use a tighter press fit between the damper hub and the nose of the crank, which reduces chatter between the damper and the crank and helps dampen harmonics even further.
Another view of the hydraulic...
Another view of the hydraulic damper installation unit.
Once the ATI damper is in...
Once the ATI damper is in place, Santelik installs the timing pointer and verifies TDC.
The cast-iron heads are stock...
The cast-iron heads are stock replacement pieces from RHS. And although they have the same general characteristics of a stock 23-degree Chevy head (for practically the same cost) the performance they provide is quite a bit better.
The RHS heads are decked to...
The RHS heads are decked to ensure each chamber is as close to the 64cc minimum as possible. Because of the rules, RCE can't do much to the chambers or ports besides cut three-angle valve seats.
Here, Santelik has a set of...
Here, Santelik has a set of the steel Manley valves in place and is checking valve clearance to the piston.
Before bolting up the Champ...
Before bolting up the Champ oil pan (complete with integral windage tray), Santelik must determine the proper oil pump pickup height. First, he measures the depth from the pan rails to the bottom of the sump.
Then he mocks up the oil pump...
Then he mocks up the oil pump and pickup on the block and measures the vertical distance from the bottom of the pickup screen to the block's pan rail. There should be between 1/4- to 3/8-inch clearance between the bottom of the pickup screen and the bottom of the pan.
RCE uses a Melling 10 Series...
RCE uses a Melling 10 Series oil pump for its Street Stock engines. The pump is a stock replacement part but has a thicker body to eliminate cracking under stress.
Once everything is determined...
Once everything is determined to be correct, the oil pump pickup is welded to the body of the pump.
Here, you can see the completed...
Here, you can see the completed welding job.
RCE went with a complete front...
RCE went with a complete front drive kit from KRC. All the components are designed to work together, which should ensure efficiency and no thrown belts during a race.
Here, you can see how the...
Here, you can see how the entire system bolts up cleanly and with minimum fuss.
The completed engine ready...
The completed engine ready for the dyno. That's a Brzezinski dual-plane intake painted up to make it look a little more like stock. On top of that is the Wilson carb adaptor that will allow the regulated two-barrel carburetor to work on the square-bore intake. In back is a DUI HEI unit from Performance Distributors that will provide plenty of spark well past this engine's redline. You can also see the rocker and beehive valvesprings from Comp Cams.
The Dyno Sheet
An engine build doesn't have much worth if we can't back it up with hard numbers. We were impressed not only with the 452 peak horsepower though a 500 cfm two-barrel carb, but also the Kansas-flat torque line. The torque grunts out 473.2 lb-ft when the dyno pull begins at 3,000 rpm and doesn't dip below 460 until the engine hits 5,100.